Rebuilding Miata front calipers

Begin rebuild of calipers

We now move on to rebuilding the brake calipers. See before donor pics.

Donor Caliper before

In retrospect I did not do this process in the best order. This is also the first time I used the product Evapo-Rust rust remover.

Evapo-Rust is a chemical method to remove rust and I was not sure what to expect, nor was I certain that the product may not cause harm to the caliper piston bores. So this is why I decided to just leave the Caliper pistons with seals in the caliper and submerge the fully assembled calipers into the evapo-rust product. I purchase a 5 gal can of evapo-rust from Northern Tool. But this amount is more than you need. I used plastic  food container just large enough to completely submerge the front and rear brake calipers into. I did one at a time.

soaking in Evaporust

soaking in Evaporust


I put the first front caliper into the solution and I was concerned that possible my evapo-rust was expired! I did buy it about 4 months ago, I do not know what I was expecting but I was expecting to see some sort of chemical reaction as I looked into the container,  but nothing looked like it was happening. My plan was to do 1 caliper a day, so I could let soak 24 hours before removal. So that is what I did. The next day I removed the caliper and I was still not impressed, but per instructions you are to spray with clean water after removal, so I hosed off the caliper and using a tooth brush I scrubbed the caliper while in a clean bucket of water. The result is well like magic. The calipers now look like new, at least on the outside! The cleaned parts upon removal from solution have a slight black film residue, I believe this is do to the rust conversion process and once you wash this off this film  the metal underneath looks amazing.

Magic of chemical rust removal

more magic

I am now sold on this product and will recommend it’s use. I also cleaned the pins and hardware, and machined surfaces look like new with no signs of chemical etching, so I believe this product would be perfectly safe if I had used evapo-rust to clean the hubs or front axles as opposed to media cleaning. The instruction also say after chemical cleaning the parts will not begin to flash rust for several days, so you have some time before you will have to paint or primer. This is a benefit of time you do not have when doing media cleaning in cabinet. See after pics. I used the same solution and container to clean all 4 rotors and I did allow each caliper to soak for 24 hours. I started on Sunday as I have plans to leave Friday and would be out of town for a week, So I decided I should just go ahead and primer the calipers with high temp KBS primer

high temp primer

Thursday before I leave and finish the rebuilding them  when I return. But of course if I remove the pistons and find a caliper with pitting I am just wasted my time and some primer. So I masked off the parts I did not want painted and I used foam ear plugs to keep the paint out of the threads. This worked out really well.

See primed caliper pictures below.

ear plugs keep paint off threads


Now begin the  disasemble and rebuid of calipers  so they are as good on the inside as they appear to look from the outside. If I were to do over would be my frst step would be to disasemble and verify calipers are satisfactory for rebuilding and then I would submerge the cleaned and disasembled caliper cores into the Evap0-Rust and remove clean with dawn and then clean again with brake clean.

I now begin the rebuild of the front calipers.

For the procedure I will refer you once again to the enthusiast work shop manual page 9:10 section 13 for the step by step instructions.

Here I will supplement the manual with pictures and some comments. Not much in tools are required air compressor to remove pistons a  5/16” line wrench and 12 mm socket. Use 12mm wrench to remove caliber bracket, and banjo bolt securing the flex line, we will not use the donor flex line as the VortX kit includes quality braided flex lines.

remove banjo nut to use air to remove piston

protect piston


Keep the banjo bolt and it is best to use new copper washer or heat the old and anneal. Next pic is removing the pistons from the caliber. I placed some wood material and an old wax pad to prevent any potential damage to piston during removal, you may be surprised.

extracted piston ready for hand removal

I used compressed air, I tried 20 Lb but needed about 35 to get the piston to start moving slowing then the all of a sudden it pops out and is restraint by my wood blocking. Make sure you keep your fingers out the way during this procedure.

using pick lift out the square piston seal


Remove and save the bleeder screw.

Inspect piston and caliper for rust and pitting. This could be the end game for your caliper if pitting exists. Next use a pick to help get the square piston seal from its groove. Next using a brake cleaner product thoroughly clean the piston and caliper and blow out the passages. I used a tooth brush to clean the piston seal and piston boot grooves in caliper. I used some 2000 wet paper to polish the piston. I also wrapped some the 2000 grit paper around my cylinder hone to polish the bore of the caliper, worked good.

polished bore with 2000 grit

used tooth brush to clean grooves

blow with compressed air



polishing piston with 2000


I used Mazda OEM caliper rebuild kit part # NAY5-33-26Z this Mazda Kit is $45.00 and about half if you decide to use an aftermarket parts store kit. There may not be any disavantage to use an aftermarket caliper seal kit but I decided to go OEM as Miata brakes have an excellent reputation for durability and thought using the factory parts will maintain their performance.

new OEM caliper rebuild parts

lubricate replacement seals in DOT 4

lubricate cylinder bore with DOT 4

Of course after caliper and piston are polished once again clean with brake cleaner, don’t forget to clean the banjo bolt and bleeder screw.

I used a foam brush to lube the caliper bore and paint the piston with DOT 4 brake fluid. I used pentosin super Dot 4 brake fluid. I do not recommend using the DOT 5 Silicon. Before installation of piston and boot cover I dunk in a cup of brake fluid.

piston boot positioned to install in caliper

ready to install in caliper

Position the boot dust seal as shown onto piston. Then insert the piston into the caliper.  Be careful to make sure the piston is square to the caliper as you apply force to insert.

fully engage outer boot seal in groove

verify boots inner seal fully seated in piston groove

You will feel a bit of resistance as the piston skirt engages the square seal, but as long as you are square keep applying force , you will be able to tell when the piston is passed the seal as the piston will now more easily slide into the bore. Next make sure the boots outer seal is fully seated in its groove in the piston skirt. Now is a good time to verify the boots outer seal is fully seated in the caliper groove, if so now fully compress the piston into the caliper.

piston with new seals fully depressed in caliper

Install bleeder and banjo bolt with new copper washer and the caliper is now rebuilt. See pic. I do plan to paint but that is for another day after all four caliper are rebuilt. Now we need to replace the piston pin rubber guide in the caliper bracket.  I used a razor blade to cut rubber guide to help assist in removing it from the bracket. See pic.

almost out

used 3m cloth to polish bushing bores

I cleaned up both caliper bracket bores using some 3M polishing pad material, see pic.

I used some Permatex ultra disk brake caliper lube to lube the pin bushings for install. I will use the same grease to lubricate the caliper pins.

lube bushing with permatex ulta and used pin as install took


Finally I install the the remaing boot, I needed some assist using a clay modeling tool, see pic. These can be handy tools for this type of work; they do not have sharp edges that can slice a seal. I think I will leave this off the other caliper until after I paint them.

clay tools helpful with seal work

Now all that is left is to polish the pins with the 2000 grit and paint, not a bad job at all. I actually took longer to write this blog than to rebuild the calipers. So I recommend removing your pistons and inspecting for pitting and if all is well rebuild them and the money saved can be used in the build elsewhere.

Next we will rebuild the rears, which are a bit more involved.



Repacking Miata Front Hubs

Repacking Miata front hubs

Here we are disassembling and cleaning the front hubs in preparation to repack with grease.

The manual says the front hubs are not serviceable. This is partially true but I did learn on the Mazda racer spec Miata community forum that most all serious Mazda racers repack even brand new hubs as normal race prep. This forum    is excellent to learn about these techniques and other Miata set up items.

As to whether we should do this will be a topic for discussion at a later date. But suffice I decided to do the hub repack as I wanted the experience of how to do this procedure.

My post here is only to supplement this very excellent article I believe was originally posted by Karl Zimmerman on the Mazda racers forum. Please click Repacking front Hubs for the full text of how this is done step by step. The photos and text are excellent.

As we noted during the parts Harvest my donor hubs had an almost nil amount of play and being quality NTN hubs I decide I will repack for use in the VortX. Grease is cheap. See pics of front and back donor hubs.

Front of NTM donor hub

Rear of donor NTM hub

rear of donor NTM hub


Label each hub for reassembly. Example DS for Drivers Side, I used A and B, put if doing again would rather classify as DS or PS (passenger

flat washers in position

flat washer in postion

side).  I recommend using the 4 washer method as in article. As you can see I had a fender washer at hand and cut in 4 pieces to do the same job. I did supplement the 4 washer method by placing another larger washer on top of the 4 individual washers; my thought was this will allow the socket a more level surface to press against for removal of race. It did not take much force to tap out the race.

20 mm socket in positon

Round up some baby food containers or prescription bottles or some type of suitable containers to keep the removed bearing races, holders and bearings separate. So you will have Hub PS  and separate container for Hub PS inner and Hub PS outer races, holder and bearings.  You will also have same for the DS hub. See pic of how I organized the parts.

all race& bearings are labeled

But before I repack the bearing I decide if I want to clean and repaint the hubs now is the time. The cleaning is a necessary step but the prep and paint is for cosmetic only.

It  is important not to get these parts mixed up or premature failure is almost certainly to result so be careful.

FYI you can use a 1 1/8″ in socket in place of 29mm as called out in instructions.


remove bearings from holder

Please click Repacking front Hubs for the full text of how on this proceedure. My pictures are only to supplement.The dissembled hubs are solvent cleaned in the parts washer and then washed in dawn dish soap, applied some WD40 to bearing surfaces to prevent any flash rust to machined races. I decided I would clean hubs exterior surface rust in the blast cabinet in preparation for paint.


home made hub seat kit


If I would do again I would use the chemical method I used to clean the calipers for rebuild. I will describe in the Caliper rebuild. As you can see I went to great lengths to prevent and media and later paint from entering hubs and getting on race surface. I used black electrical tape to cover the inner circumference edge of hub. I was as the home depot and I found some bathtub drain gaskets and round furniture sliders with Teflon face that I would use to make seals for the open ends of the hubs. Bought some 3/16” bolts nuts and washers to compress the gaskets and sliders against the hub ends, I even went so far as to use silicon applied to the washers to further seal out media. See pic.

the seal parts in order

hub sandwich


This actually only took a few minutes to prepare for use. as I only had to drill 3/16” holes in the center of the sliders and then screw together with the hubs as the middle of this sandwich. It did work great. See pics of hub sandwich. I media cleaned, air blasted and then washed the hub sandwich in dawn soap to prepare for paint.

media cleaned on left

Preped ready to repack

I painted the Hubs with KBS silver rustseal coating. While I had the spray equipment out I also painted the spindles and brake covers with Bill Hirsh aluminum engine enamel. Bill Hirsh offers several quality paints at As you remember I had previously primed the spindles. The KBS rustseal coating I used for the hubs is applied to the bare unprimed media cleaned surface as no primer is recommended for rust prevention. If the parts are to see direct sunlight this KBS rustseal coating will need top colored top coat. but the hubs are not in sunlight and besides hubs are maintenance items anyway. I then applied to all painted parts KBS diamond finish clear coat. This needs to be applied within 45 minutes of top coat or you will have to do additional surface prep so plan your paint work in advance to save time. After the paint was dry I removed the bolt and the Teflon surface made separating the sliders easy. I wish I could take credit and say I planned it that way, but actually I was going to use plain wood when I saw the sliders for sale on the way to the check out counter and they were the correct diameter  and  did not require any effort for me to cut any wood to size. So now we have cleaned, blasted and, painted hubs.

painted and looking good

I also learned from the Spec Miata forum that Red line Synthetic grease is the most recommended go to grease for this job. I thought I would have to wait and order this grease but after going to redline web site I found out there is a redline distributor only 1 mile from my shop I did not know about! Most hub packers re-use the old seals but I purchased new seals. These are not available from Mazda, but  Dave Wheeler of Advanced autosports has went to the effort to have replacement hub seals manufactured for the hubs and are available at Dave’s website for racers to purchase. Dave has also authored a book I recommend title the Spec Miata Constructors Manual and is worth the read. I did not damage my seals during removal and could have reused, but decided to use seals the new seals.


Hub, cleaned parts ready to pack

Here is one hub. I have allready cleaned the hub races thoroughly with WD40 and also all bearings, inner races and holder are cleaned and put in labeled sanitary container ready to be repacked.

So with Red line grease in hand and my new seals and the above file on display on my computer screen it is time to get on with the repack.

I start by repacking the hub’s rear race first. This is the easy side to do. I applied Red Line synthetic grease to holder and installed the ball bearings. Pay attention to how the bearings fit into the holder. Notice you are pushing them in from the outside or downward as you are viewing from above. If you try it put bearings in center of circle and then try pushing from the center of the circle to outside of the circle they will not go into place and too much force may break the holder. Make note of this as this technique

will come in handy when you install the front side holder and bearing.

Next I applied a liberal amount of grease to the inner hub race and then dropped the holder with bearings into the bed of grease.   I applied some grease to outer inner race and with aid of socket I tapped into position see pic. Then clean up the extra grease and take picture.

grease applied to rear race


apply some grease to rear race

Tapping race into position

So far so easy. Now we turn the hub over to repack the front race. This is a bit more difficult. First I applied some grease to holder and work into position. This is the scary part as if you break the holder you can only get the holder when you buy a new hub! I found holding the holder about 60 degree angle from horizontal worked best for me. You will have to compress the holder slightly to get into position. You may not want to do this in cold temperature, not sure but winter temp may affect the pliability of holder. Once the holder is in place it is time for our next dexterity test. It was so easy to install the bearings when they are on the work bench; I thought this would go fast too. It took me a few times to find the best technique. Like the article says, installing the bearings 180 to each other in sequence does help. But the trick is to hold the retainer in position with the index finger of one hand and push the bearing with the index finger of the other hand, Like you are trying to hold the bearing between the tips of your pointed index fingers, remember the bearing go into place from above easy when we did the holder on the bench, Same here. Once this is done you are home free. After bearings are in place apply a liberal amount of grease and coat the front inner race with grease and tap into position.

front holder in place

Next tap in the front inner race and all I have left to do is to install the inner seal. See pics for orientation.


Orientation of grease seal

Just start the seal square , I was able to push on by hand and then used a socket and lightly tapped to verify fully seated. I was able to repack the other hub in half the time. Overall repacking the hubs is nothing to be afraid of . If your donor has quality hubs with play within spec, why not repack and reuse?  On the other hand if your donor has low quality hubs and you plan to take to take your VortX to the track you may as well just bite the bullet and buy new hubs now.

Looks like the front brakes are missing,

So the next post will be rebuilding the Calipers.

Before and after pics here.

degreased spindles

VortX Ready




Refurbishing Miata front axle parts

Starting at the front.

I am going to refurbish the donor parts starting from the front axle and working toward the rear axle. I start with refurbishing the front end parts, the spindles, hubs, and brakes. All other front end parts furnished in the VortX kit are new! Actually if you want you could just install the parts as removed from the Miata provided they were in good working order, but I do want a pleasing and sanitary car so I will spend some extra time and effort and some of the budget in this area to clean, coat the parts and rebuild the calipers.

I start by removing the dust covers from the front spindles, us a 12 mm socket to remove the 3 dust cover bolts. Next stop is trip to the parts washer. Which in itself is worthy of some comment.

remove dust shield

What to use for solvent? I did a lot of searching around. The solvent cleaner must be aluminum safe. The leaves out such readily available cleaners like purple power and such. In fact most all cleaners are caustic to aluminum it seems. I purchased Crown PSC 1000 in a 5 gal can. You can usually walk into a Tractor supply pay them $41.99 and take it home so there is not any shipping expense. Besides the price the reason I selected it is this solvent is this product is a medium aliphatic Naphtha solvent and is a recommended solvent by Boeing aircraft to use in degreasing of aluminum and is not caustic to aluminum. It is flammable and should be used in ventilated flame free area and of course wear gloves when using. I located my parts washer on an enclosed patio next to my shop. So this works out great for me.

cleaning in washer

Since I bought the Red Devil and on occasion I rent a 2 seat Symphony 160 on occasion to fly, I investigated what I could use to clean these bare alcad aluminum airplanes. I found something I should already have known about. This is Extreme Simple green. This is not the same simple green you buy in Wal-Mart. In fact you will probably have to order it and have shipped. I found prices on Amazon for as low as $79.00 including shipping for 5 gal pail. You can buy from It is made to clean aluminum.

degreased spindles


This product is water based so it is not flammable. But the big plus for this product is that it meets Boeing spec D6-17487 and Pratt Whitney spec PWA3609. So it is safe for all metals! Degreases and offers corrosion protection too, does not harm paint, plastics, coatings, low odor, can be used in parts washers without need for heating. Sounds like great stuff. I have not tried it yet but I plan to order some soon.  The same material is also marketed as motor sports cleaner and is sold in some race shops. You can put this in a bucket with water and wash your monocoque aluminum chassis and painted body and just hose it off. So this is just a FYI about an alternative cleaner you can use in your parts washer or to wash your car or airplane. I’ll update when I give it a try.


media cleaning dust covers


blasted ready for primer



Back to task at hand. After cleaning spindles in the parts washers I wanted to prepare for paint. I washed the parts with dawn dish soap. I have a bead blast cabinet and wanted to use it to remove all surface oxidation. The medium I am using is glass purchased from I wanted to make sure I do not damage any machined surface. So I had an idea, hmmm. How bout if I paint all the machined surfaces with plastic coat? You can buy this stuff at any craft store. My nephew uses this stuff to stencil race numbers on his car for track days, does not harm to the paint and peels off easily and this is a common practice, so this is where the idea comes from. So I give it a try and coated the spindle surface with the plastic coats. See pic. Next spindles are bead blasted.

media cleaned on left

grinding off cast flash

Looking good but I notice some casting flashing that could be a stress riser. So I get out the dremel and grinding stone and do a bit of clean up smoothing our any crevices. For this process it does not hurt to use a little extra caution to protect the spindle, in case of a slip of hand and dremel. The cardboard tubes from empty paper towel rolls came in handy. See cleaned up pic. If I was building a “show car” the process would be to spend many, many hours to remove metal to such an extent to have a smooth almost polish surface. My goal is to use the Miata parts with minimal cosmetic time and effort. In fact this step is not necessary, but since the VortX RT suspension is more visible I decided to clean up the bigger gobs of casing flash since it is now or never.

used plastic coat to protect machined surfaces

plastic coat applied

Of course immediately after clean media blast you want to apply coating. Prior to paint I used more corks to prevent paint from getting into the tie rod and upper and lower ball joint holes. I painted using my old faithful and very low cost Rust 0leum heavy rusted metal primer. I will top coat.

spindles ready for paint

Since I primed these parts I have become aware of a product called RustSeal made by KBS coatings. Can be applied direct to blasted parts. I used this product to repaint the aluminum heel scuff guards on the floorboards of the airplane. This is some tough paint. Other paints always have worn off quickly. I tested this paint and it is fuel proof. Only issue is KBS web site says the color is not stable in sunlight and would need a top coat when exposed to direct sun, but  this coating is extremly chip and excellent as rust prevention. So this is probably a tougher more chip resistant primer than the Rust Oleum. But not inexpensive at about $15.00 a half pint. All we need to do now is finish paint the spindles and brake dust covers. I will top coat later along with the cleaned and repacked front hubs. Which is a good place to start the next post.


Prepping for degreasing

remove ignition harness


We recently finished the disassembly and this post begins the next phase which is to refurbish the donor parts for the build. The first step is to clean the parts and I start by preparing the engine for degreasing. I thought best to remove the all electrics from the engine so I can degrease. Unfortunately I am writing this 5 months after I did this work using my notes I took at the time, and some of the details are a bit lacking. My resolution is to write this blog within 48 hours any procedure which is about the length of my memory these days. With the engine sitting on the mobile stand I made we have 100% complete access. I uncharacteristically just jumped right in and did not read the manual in advance, Now would be a good time to take several picture of the assembled engine including all the fuel injection harness, alternator, remaining electrics, hoses etc to reference for reassembly.  I wish I took a few more. You always think at the time you will never forget where this hose or that connector goes, famous last words. I am consulting the manual as write the blog to give some reference to my disassembly.  I started by removing the fuel rail. Use a 12 mm socket to remove the 3 securing bolts and collars which will come loose when bolts are withdrawn. I was not able to remove rail until I used 10 mm socket to temporarily remove solenoid bracket to allow removal of rail. I thought I could remove the rail with injectors and harness as a complete assembly.

12 mm to remove bolts

removing fuel rail bolts

fuel rail now free

This plan was not working out well and I would have known that if I reviewed the manual 5:20 P 19:  Per the manual, remove PCV hose from cam cover (obvious) and disconnect any hoses that are in the way. Next you will need to release the main electrical connector of the fuel injection rail harness. The harness is also attached to the rail with cable ties, cut the ties. Next you will need to remove the individual injector electrical connectors.

harness disconected remove injectors

Use a small screwdriver to apply pressure (but not too much, use care) to push the locking release tab. Now you can remove the rail harness. I labeled the connectors and removed the injection rail harness. Remove rail and pull to release injectors. Of course all these parts are labeled and put in donor pile for safe keeping. Review the pics.

Next I turned my attention to the coil pack. Refer to 5:27, P 27B in manual. Use a 12 mm socket to remove 3 coil support bracket retaining bolts.  Remove coil and ignition wires, put in donor pile.

remove coil bracket


Next up remove alternator, remove the adjustment strap inner bolt and the adjuster bolt you need to remove the pivot bolt,.





Then I have an OOPS moment. The engine stand 2×2 angle did not allow the removal of pivot bolt. So I had to remove the angle to free the alternator. Next I removed the exhaust header shield. Use 10 mm socket to remove 7 bolts and 3 nuts.

So If you are reading ahead, remove the alternator prior, if you are using this low buck angle engine dolly.

remove heat shield


I put the shield in the maybe pile. Next remove the AC compressor mounting bracket from block. Use 14 mm socket to remove 4 bolts and use 12 mm socket to remove 1 long bolt from front. Put this very Heavy bracket in the scrap pile where it belongs.

remove AC bracket


AC bracket front bolt removal




We are almost ready to degrease. So I went to the craft store and bought an assortment of corks and plugged any and all openings we would not want to get wet.

seal opening from debris, water

I moved the engine and diff outside for degreasing. Used Engine solvent and several stiff brushes and with the aid of the power washer and repeated the process for areas that needed additional cleaning , now the engine and differential are looking good enough to transplant, but I believe they will be in for some additional surgery before they are VortX ready, but it is always nice have clean sanitary parts to work with.


degreaing diff




Next we continue refurbisment. I want my car to have a good clean appearance and will be conditioning the parts, painting and detailing as such. But I should note that I do not have any attention to make a show car from my kit. I  will be using my VortX as a track day car so it will be seeing hard use and no need for elaborate paint and finish, but still want an VorX RT with asthetic appeal and my goal is to do the parts prep at reasonable expense. That is what is to follow.








I’m Back, finally

The question is

Where the hell did you go?

Actually a couple readers did ask that exact question, at least someone is reading my ramblings.

I was attending the other congregation for the summer, that is my excuse anyway. I’ll explain.

The short answer I used all my available (and not much) build time with aviation related activities.  I was busy detailing steel during the summer construction season and with the business end of Fastcraft motorsport.

My Lark Experimental airplane

After last post I knew I was going to be gone a couple of weeks to visit my girlfriend of over 10 years who now lives in FL. We’ll upon return I was very busy just getting caught up, as typical after a few days away. I received an e-mail from the daughter of a pilot in the area that passed away and she asked me to identify an airplane her dad was building in his garage. If you are not aware I am a private pilot, but at the time of this request I was not a current pilot, meaning I did not have a current Medical, bi-annual and my experimental airplane was out of annual, so in other words I am grounded. The daughter was having an estate auction of all her father’s items. I agreed to meet her and ID the airplane. I recognized it immediately as a Sonerai Formula V race plane as I use to own a Sonerai. I did not know the gentleman who passed away but could tell from his extensive collection of tools and equipment and interest I am sure we would get along well. Now all his toys and basically a life time of homebuilding hobby are up for auction. Looking around I spotted 2 Buick/Rover 3.5L complete V8 engines and a spare block. I immediately think VortX RTV8. I did not want the airplane but a good friend of mine who lives in SC is former V racer and expert in this airplane and he was interested if the price right. The airplane is about 85% fabricated. I ended up buying the airplane and the Buick V8’s at the auction and selling the Formula V to my ex hanger mate and I ended up with the V8’s out of the deal.

formula V race plane project

I always I told myself I would never allow myself to become a non current  pilot which was my current status. Well buying and selling this airplane made myself feel guilty. I also was aware my airplane was hangered without flying for several months. I was concerned any further neglect may end up costing me dearly down the road. So I decided to do something about my airplane and non currency. This was the catalyst that started a chain of aviation events that basically took up my building time and summer. I passed my medical, always a relief. Something you need to do every two years. Then I spent time doing airframe maintenance going through the airplane and getting it ready for the annual condition inspection and sign off which must be done by a registered with FAA A& P mechanic. Once that was done it was time for me to take the bi-annual flight test and review. Every two years pilots a take few hours of book work and a flight performance test. Then during this time I had an inquiry of someone wanting to buy my airplane. Something I was not planning, but I would like to get another airplane in the future, just was not planning the future to be now. Well I made the mistake of looking in Trade a plane to see what may be available. I found an airplane that really interested me and is exactly what I am looking for in an airplane. I always wanted to own a Midget Mustang racer and actually have first refusal on a very beautiful midget that will become available next year.  The Midget while fast and able to cruise at 185 mph on100 HP is strong enough but actually not the best airplane for aerobatics which is something I wish to continue to learn how to perform. The Midget does not have inverted fuel and oil systems and since they only hold 15 gal of fuel are limited in cross county travel. The airplane I found in trade a plane is rather rare. It is a Zenith Acro Z 150 nick- named the Red Devil.

picking up the new project

It made it’s Debut in 1980 atOSHperforming in the aerobatic show. It is stressed for plus and minus 12 G loading. Has inverted fuel and oil systems and even smoke! Cool. It also has a 26 gallon fuselage ferry tank that gives this airplane great range of 600 miles! It has a 150 HP engine that will burn about 1.5 gallon more per hour than the Midget but it still can cruise at near 180 MPH. So this airplane does all I every want to do. It has

acro Z home in shop

some historical significance since this airplane was built by and was the personal airplane of renowned airplane designer Chris Heinz. Kind of the airplane version of owning a car that was build by Colin Chapman. A deal was struck. I feel I bought it at a bargain price which makes it all the sweeter deal. But the down side is the airplane is also out of annual and has not flown in over 4 years.  The seller of this airplane decided he wanted to repaint the airplane and stripped it of paint, but before he could repaint, he was involved in a bad car accident and was in hospital for several weeks.

He is OK but he will never be able to pass the medical for his flight certificate, and this father also a pilot recently quit flying. So the airplane was listed for sale. So one weekend with help of friend we made the trip to Chicago to two the airplane back to east Ohio. Ends up the person who acquired about my airplane did not buy it, at least not yet but that is fine by me as it will give me something to fly to keep current.

Red Devil at Oshkosh


Then every year at the end of August my EAA chapter holds an annual Wings and Wheels event at the New Castle Muni airport KUCP. I started this event 6 years ago.

We had only about 5 airplanes fly in first year, but the event is growing every year and now over 115 airplanes flew in and 265 custom cars attended. In fact the residents in the area look forward to our event. Kinda now feel obligated that the show must go on. Our chapter is small and looks like I am the permanent chairman of this event. The 3 or for 4 weeks leading up to this event is almost a full time job and certainly no time to build. So that is how the summer went or in other words it just seems to pass by. So to explain the congregation comment I made at start. I was watching Speed Channel several years ago when they interviewed GM new product development manager Bob Lutz. He mentioned as a young man he raced motorcycles, was a Marine and civilian pilot and race driver. Lutz commented Motorsport to him was like a second religion with motorcycle, airplanes and race cars as the trilogy. I thought to myself I may be a member of this congregation. So this summer I attended the aviation congregation. But I am now full time attending the Locost Seven congregation until this VortX RT is on the track and road. The Red Devil will have to wait.

On with the build, Now where did I leave off. Better read my own blog!

Below are some Fly In Pics. You get a great variety of airplanes and cars at the wings and wheels event. Just a few pics to show. The Ferrari Pics were from another local fly – in I attended.But the Enzo is worth notice as well as the yellow Ferrari of a model that I am not sure ,but I believe it to be very rare and at one time was part of a museum collection. Maybe a reader will be able to ID model. It is real not a kit.




1901 Steam Car




The Stig, Cool plate




Ferrari Model ?









Removing miata donor parts 9 of 9, engine removed & we make an engine dolly

It is too long since last post. I really need to make it a rule to write the post within 48 hours of doing the job task. This is easier for my memory.

My nephew was in town from TX and 48 hours turned into a couple of weeks. So here goes. At my last post we only had to remove the engine from the sub frame or should I say the sub frame from the engine. So that is what I did next.

Use a 14 mm socket with short extension to reach the engine mount retaining bolt through the recessed round bulkhead access located on the underside of the front sub-frame. See pic.

Remove mount nuts

Repeat for other engine mount. Remove nut and large flat washer. See pic.

Remove prior to engine removal

After bolts are free I used the engine crane and lifted the engine free of the front sub-frame. I little wiggling of the sub frame was needed to assist. This engine mount is broken, See pic.

This mount was broken

The rubber part should have stayed with the fabricated bracket still attached to the engine. I have ordered MazdaSpeed competition engine mounts for the VortX build. I am creating a growing list of list of all the Mazda and aftermarket part numbers used in refurbishing and building the VortX, I will publish this list for builder’s reference.

See pic of metal brackets that the new MazdaSpeed Competition will cradle.


Put these metal brackets and hardware in the donor parts pile. This was bout a 10 minute or less job.

With the engine suspended above the front sub-frame,

front and rear subframes


I picked up the sub-frame and moved it out of the way. But now what am I going to do with the heavy engine? I really did not give this enough for forethought and I do want to be able to move this around the shop.  After looking the engine over I noticed a pair of vertical holes you will find them if you look behind alternator and just below and in front of oil filter and similarly on the opposite side of the block. This gave me an idea for a very simple and cheap way to support and move the engine around the shop. I found some rusty 2x2x1/8 angle in my garden shed and a piece of 2×4 wood framing I will use to make an engine support. I cut the angle stock into two pieces 10-1/2” long. I then drilled two holes in one angle face     ( where I will bolt to the engine block) I located the top hole 1 1/8” (STD steel gage) from the back of 90 degree bend and the same 1 1/8” from the end of the 10-1/2” angle. I then located the second hole 1 -13/16” below the first hole location. I drilled the holes using a 7/16” drill. These two holes will bolt the angle to the engine block.

Now using the same 1 1/8” gage I drilled a 3/8” diameter hole 1 ¼” up from the other end of the 2 and ½”angle and on the opposite face of angle. This hole will bolt to the 26 inch 2×4 with 5/16” x 2” bolts. Cut the 2×4 to a length of 26 inches.

Make another angle to be a mirror image of the first.

HOLE LOACATIONS, Note: 45 deg notch on angle to right

I trial fit the angles to the block and I had to cut a 45 degree corner off of one angle face to clear the oil filter. See pics of the rusty angles with drilled holes. I decided I would paint the angles prior to use so I will finish this support frame tomorrow. So at this time I used a 14mm socket to remove the bolts that retain the steering rack to the sub-frame. This is not a necessary step and if you want you can leave attached to the front sub-frame, but since I am waiting for paint to dry, now is a good time to remove the rack. The VortX comes with a brand new quick ratio rack, so I am only removing the donor car rack to put in the e-bay for sale pile.

I painted the rusty angles with Rust-oleum rusty metal primer, this is my favorite paint for any ferrous metal refurbishment projects and I would like to make some commentary about this primer.

I have used this primer for years and I am most impressed on how it prevents return of rust. I first used this primer many years ago to paint a pipe used for a mail box support. My only preparation was to wire brush the major rust scaling off. I did not fully remove the existing rust and painted over the remaining rust with Rust-oleum rusty metal primer, I did not bother to put a top coat on. I fully expected it to return to the fully rusted condition in very short time. Long story short, this pipe looked as good as the day I painted it several years later! I have since used it many times and always with the same outstanding results, it really does the job of preventing return of rust. So for this reason I intend to use this paint as my go to primer for any parts that I recondition by stripping, bead blast etc. prior to finish painting.

For example I intend to paint the uprights and the differential and front and rear hubs. The differential and hubs will be subjected to some moderated but not high temps. Will this paint hold up? So I decided I would do an experiment to find out. I used a 3 inch piece of the same angle used for the engine stand and painted one side of the angle with this primer and the other side with VHT engine enamel. I put the piece in the oven at a temp I estimate the max for these parts of 200 Deg F for several hours. Both test samples held up great. So I kept turning up the heat and after 12 hours at 450 Degrees F, I removed the samples and using a primitive and unscientific test of a scraping a knife along the painted surfaces, the Rustoleum sample held fast and surprisingly the VHT paint was soft and some scraped off! So while I do not intent to use this primer for engine or brake calipers, I feel assured this is good primer paint for all but high heat applications. After the paint dries I was able to find 4 bolts from my coffee can of bolts I removed during disassembly to fit the holes in the engine block to mount my now nicely painted and dry angles to. After bolting these angles in place, see pic


Angle bolted to engine block, notch for oil filter

I clamped the 2×4 to the front face of the angles. I made sure the bottom of the 2×4 was about ½” below the angles so the angles would not scrap the floor surface. I marked the holes and drilled using a 3/8” drill. Then I bolted the drilled 2×4 to the face of the 2×2 angles using 5/16” bolts, see pic.

I then decided I wanted to keep the transmission off the floor and simply cut a piece of 2×4 to a length of approx 4-3/4” and positioned below the rear transmission mounting and marked and drilled ¼” pilot holes. Then using 2 ½’ x 3/8” hex headed wood screws I bolted the wood to the trans mount. Built as described the bottom of the 1.8L engines oil pan is about 1” above the floor surface. Adjust your angle lengths to suit if more clearance is desired.


Now that the engine trans unit is safely supported I still have the problem of moving it around the shop. My original plan was to buy some castors and attach directly to the stand I made, but then I read the Harbor freight flyer and seeing 1000 Lb capacity 11 ½ x17 ½ furniture movers on sale for about $10.00 each I had another and very simple plan.

I bought two of these and stopped at Lowe’s bought a precut 1” x 8”x48” piece of wood used for making stairway runners. I also picked up six 5/16” x 2” lag bolts. I simply drilled three 3/8” holes in each dolly and bolted the stair runner to it. Very simple and easy to make. I used the engine crane to lower engine onto this mobile “skateboard” platform. It works great and I can easily move around the shop and I am sure this “skate board” will find future use for other purposes. With the engine stand completed we have now concluded the deconstruction phase of this project and this will be the last post under the harvesting of donor parts topic heading, hence “last stand” post title.




I must admit I was not looking forward to the disassembly process. But it went much easier than I thought and I actually enjoyed it and this was an excellent way to learn  details about the Miata that will serve me during the build. I now have a good assortment of quality parts to sell that should allow me to recover most of the initial expense of the donor purchase. I invested a total of less than 40 hours in disassembling the donor and half as much writing the blog. In retrospect using the Miata as a single donor to build the VortX is to me is a “no brainer” and I highly recommend to potential builders to buy a Miata( go to Co-Part to find your donor Car) and do the disassembly yourself. You will learn a lot and this is a very cost effective way to go.

Now I must say I am very much looking forward to the next phase of this project.

What comes next? Well before we can get into the build I will first need to refurbish some of donor parts for the build. So the topic heading for my next post will be  Refurbishment of the donor parts. Will be posting soon.


Remoivng miata donor parts 8 of 9, only 2 bolts left

Since last post I gave a thought , that maybe the next step should be to  remove the engine from the sub-frame, but decide I may need this mass to resist torque of removing ball joint castle nuts. It turns out this was the right decision.

First use a 17mm socket, which seems to be the go to socket for the suspension, and remove the lower bolt retaining the strut spring unit to the lower control arm. Repeat for the other side and put the strut spring units in the e-bay pile.

Next up I did remove the wheels to access the ball joint and tie rod  cotter keyed castle retaining nuts. You need to support the weight of the engine unit with the wheels off. Use jack stands or suitable support. As you know I do have the engine crane in position with the legs under the sub-frame. I place a couple of pieces of 2×4 material on the top surface of the engine crane and used the legs of the engine crane for supports, worked.But it may be possible to break loose the castle nuts with the wheels on, if so do so. First remove the 6 cotter pins from upper and lower control arms and the two tie rod ball joints. Use 17 mm socket to break loose the tie rod and the upper ball joint castle nut, not need to completely remove.

brake loose upper castle nut

brake loose tie rod castle nut





You will need a 21 mm socket to remove the lower ball joint retaining nut.

brake loose lower castle nut

After the castle nuts are loosened go ahead and remove the wheels and tires if you have not done so by now. Slide brake rotors free of hubs, and use the 29 mm or the more common 1-1/8″ socket to remove the hut retaining nut(which we have previously loosened). After the nut is completely removed the hub is now free and and be removed from the stub axle see page 9:21 in the manual. Repeat for other side and place brake disk along with calipers, hubs and retaining bolts and nuts in the required donor pile parts.

Now we need to separate two tie rod ball joints and 2 upper and 2 lower control arm ball joints. Refer to 8:16 in the manual. As you read the manual you will find out they were not able to purchase a separator tool that would fit. They use a wedge chisel separator and big hammer and brute force. My ball joints were very, very tight and I would not encourage anyone to remove the joint is this manner. I was able to buy an inexpensive 3/4″ ball joint separator tool for about $20.00 from Harbor freight. Their tool item number for this separator is 99849. You need this tool. It fit perfectly and made what could be a very tough job almost easy as I was able to separate all the joints and remove uprights in about 2 hours and that includes my time to make notes for this blog.

You NEED this tool!

I did one side at the time. I started by removing the steering rack tie rod ball joint first. A couple of suggestions for using this tool I loosed all the castle nuts until they were about flush with the head of the threaded part of the tie rod. You will soon find out when the tie rod breaks free of the Morse taper that it can be rather explosive and I thought it a very good safety idea to leave the castle nut in place to contain this separation.Also as  hint use some WD40.After tie rod is separated, remove castle nut completely and release tie rod from upright.

separating a tie rod ball joint

To left is the separator tool in position with the castle nut in place to contain separating parts.Make sure tool is in proper position, It is OK to tap  the forked end into place with a hammer to get proper insertion.

separator in positon on top joint

For the larger lower  joint you will need to adjust the separator tool to use the upper ( you want to increase the spread) pivot pin holes locations.You can see the different pin position in pictures.

Some suggestions on use of tool. I did apply WD 40 to taper joint area prior to positioning of tool on the ball joint. You will use your ratchet or breaker bar to turn the screw on the separator tool.

After several turns and the breaker bar is providing quite a bit of resistance to turn screw, this is when you are thinking to yourself, I can not believe it has not broke loose or something is going to break, Well this is the time to get a good heavy hammer and give the ball joint a swat with the hammer. Using this method two of my joints immediately separated. For the other I would tighten the screw anther half turn , then give it a few swats and then another ½ turn and with the next hammer blow it separated. Only one of my joint separated without using the hammer technique.

It always is amazing to me just how much retention force a morse style taper can provide with out any bolt applying pressure.  Many of the lower HP aviation engines attach the prop flange to the crank with a similar taper. I once needed 20 tons of force to remove a prop flange!. So it was expecting it would and should take some force to separate the joints from the upright.

So after all your joints are broke loose, completely remove all the castel nuts and remove the upper ball joint first from the upright and then lower, the upright is now free.

lift upright free of ball joints

Put the upright in the required donor pile parts and repeat for the other side.Here is a group portrait of the front end donor parts including the wheels.


Below are a couple of  pics of the donor parts before recondioning. Hopefully they clean up an be VortX worthy.

Well this concludes todays post. Basically all we have left to dissasemble is to remove the engine from the subframe motor mounts. Just 2 bolts left.

Stay tuned.

Front end donor parts, wheels

front caliper before pic

front upright with brake dust cover


front end donor part group