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My F-Prepared Autox Evo 9

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I am going into the third season with this car, and have pretty much rebuilt the whole thing since purchasing. I will try to keep the chit chat to a minimum and let the pics tell most of the story. But here is a "most" of the parts list, since I find them helpful for discussion and other peoples research.

This is the second fastest door-slammer class in autox, and because of the mix of vehicles we have to run the car at 2700lbs (2270lbs unballasted weight), and it breathes through a 46mm restrictor.

Engine: Must retain stock geometry in Prepared class.

Eagle Crankshaft

Manley 10:1 Gas Ported pistons w/HD pins (.200 wall)

Manley Turbo Tuff I-beam rods

ARP Main studs

ARP Custom age 625 head studs

Kiggly HLA regulator

GSC beehive valvesprings

Custom 8 qt wetsump oil pan.


ETS V-band turbo manifold (custom built with 1 gate to shave weight, since we don't need another with a restrictor)

Garrett g25-660 Turbocharger

Turbosmart 45mm wastegate actuator

Printed Carbon fiber filament 46mm restrictor.

Custom built 3" exhaust


Meziere 65gph Electric water pump

Honda civic trunk mounted radiator

Denale 2200cfm Brushless fan (thing thing pulls 60AMPS!)

Engine/drivetrain management

Haltech Elite 2500 ECU

Haltech Street display Dash

Racepak Smartwire PDM

Racepak CAN button pad

Haltech WB01 wideband controller

All the associated logging sensors etc. oil pressure, fuel pressure, MAP, IAT etc.


SSB Designs Billet drop spindles at all four corners. Front utilizing custom steering arms to fit 16" wheels.

Koni 8611 Double adjustable struts, custom valving Typical spring race is 800lbs/in Front and 1300lbs/in rear on asphalt.

Works rear sway bar

ESM race spherical bushings all around

Custom rear trailing arms to shorten wheelbase and clear tires.


TRE built 5 speed trans

Non-acd Transfer case with ATS carbon hybrid front differential. 4.0 Final drive.

Aluminum front half driveshaft

OS Giken Rear differential

Exedy Twin disk clutch

Magnus Clutch Delay valve

Torque solutions mustache bar delete

Torque solutions engine mounts, custom built front mount to clear intercooler.

I think that is most of the basics I will try and give more information with the pictures that follow.


Some pics from the week before out first event with the car after purchase. There were many small issues with the car. The biggest being it still had poly bushings on it, and the arm pockets and such were deformed from failing bushings. It also had a bent front knuckle which we replaced.

We cut some custom camber/caster plates as well as the others were standard caster setting.

We installed a complete ESM Spherical kit in the car, and checked for proper bump travel height. We also started test fitting the pre-production SSB Designs front knuckles at this time.


We completed two events that season, winning both of them pretty well.

That winter is when we really dove into the car. Shaving weight and shrinking mass toward to the center being the primary goal for the year.

We also upgraded the engine management during this time, keeping the stock ABS per class rules.

I will let the pics do the talking, feel free to ask any questions if you have them!

One of the first things was figuring out how to mount 300+lbs of ballast as far back as possible. We decided to cut the tank down, and create a rack system to hold a BUNCH of steel in the optimal location.

Next up was a new cooling system, the other one was heavy gauge aluminum tube and silicone couplers. We upgraded to lightweight nylon hose and AN fitting throughout the system. As well as new aluminum radiator.

We also mounted the intercooler inside the frame, down as low as possible. Then ducting was created to feed it through the original mouth. We are not allowed to modify any of the structure in this area of the car, so it ended up being a complex part.

Wiring the car continued at the same time as well this work. Once the major components of the car were in place we began running wires and weeding out what we didn't need.

We started with a hand-drawn diagram to help the process go smoothly. It is also important to have record of this stuff in case you have issues at the track. Especially since I co-own the car, everyone being up to speed makes a big difference when things go wrong!

This was basically the completed engine bay for season 2. using a stock manifold and FP green turbo through a carbon restrictor is made about 440whp/440wtq

This was the starting weight for that season. Small upgrades and improvements eventually made it around 2200lbs.

The car complete and as Race in 2018.

Our first trip to nationals landed us a Podium after some diabolical weather. I had enough speed contend for the win, but coned my fastest run on day 1. The proof was there that the car was one to beat!

After the inspection from that race we found that the turbocharger had been damaged. Likely from over-rev (easy to do with a retrictor), so we needed an upgrade.

We decided to try the then Brand-new Garret g25-660. This being a little bigger than we actually needed to make the intended power, with the goal being to keep the car on the choke for as long as possible.

ETS being local, they helped us out by making a custom single gate version of their v-band manifold for the car.

We also needed to quiet the car down some since we were building a new downpipe. This also meant that we needed to build our new oil pan, as on concrete at 1.3+ sustained g's we were seeing some oil pressure dips in the log. We decided to build a trap door, center sump pan, and re-route the exhaust.

Our car runs no accessories, since it is all electric PS/WP, and we run RC lipo style battery packs to power the car.

This pretty much solved the issue of starvation and also holds around 8qts of oil. We didn't loose any ground clearance either thanks to the downpipe now being routed around the side of the pan.


We also installed the recently developed SSB Rear knuckles at this time, and a lightweight drag-racing style brake package.

We printed a new restrictor for the larger inlet. We were very surprised to gain this kind of power from a 46mm restrictor. This turbo is just amazing at very high 4:1+ pressure ratios. Eventually making 560whp@30psi RESTRICTED!

With the binds in the rear suspension fixed because of the spindles. We worked some more on the front and were able to get the car lower. The crossmember height being set at 2.25" in front.


Some photos from National tour and Pro solo events in our area last year. We added a line lock to use to preload the drivetrain for launching, in conjunction with the Magnus clutch delay valve we were able to achieve 1.6 60' times on unprepped asphalt. Leading to a dominate performance in the Pro solo.

We also ran some front brake ducting, as the brakes got hot they would bias themselves more and more toward the front. Because of the small diameter wheels we are limited on brake option, so this was done to try and make them more consistent through the runs.

Also a shot of the car hooked up to the charger between heats!

That pretty much catches us up to this year. We have a few small changes we plan to make this year. I will try and document them here!

Thanks for tuning in, if you have any questions I would be happy to answer!


Very cool project. Thanks for keeping it posted.