BUILD-OFF CHALLENGE: MichiganMat Options

[MichiganMat]

[Andyrew]

Curious... What do those calipers look like on the rears? I've got vented rear rotors and spaced out stock calipers.... Would love more rear pad.

[Retroracer]

Matt - are you going to plug weld the original holes in the strut before drilling out the new ones? The new holes you marked up look rather close... Also, what thickness rotor are they designed for?

- Tony

[FL000]

Cool build; just binge-read your thread. You made some quick work of getting it on the road.

[MichiganMat]

Matt - are you going to plug weld the original holes in the strut before drilling out the new ones? The new holes you marked up look rather close... Also, what thickness rotor are they designed for?

- Tony

Hey Tony,
Yeah, the holes will be filled and Im going to add material all around the new holes with the welder to really beef up the connections. Then I'll machine the surfaces, should look close to "stock" when Im done. Im pretty sure the loads are distributed in safe directions, but going to weld in some insurance anyways. Pics coming shortly.

As for the rotors, the Volvo 240 caliper came in two forms: The early caliper (1975-1985) was for non-vented, the "later" caliper (1986-1993) was designed for the same size 298mm x 28mm rotor we use on the early Porsches.

The calipers weigh a bit more fully dressed (11lbs Volvo 240 vs 9lbs for the Porsche M caliper), but its worth the benefits of the larger pad IMO.

Like I said, its a skunk-works project, Id be lying if I said I didn't have a bit of anxiety about messing with the /brakes/ of a car I'll be driving on a race track. Going to try anyways, approaching the mod with the utmost skepticism.

[MichiganMat]

Big updates from the MichiganMat garage!

My 1yo has been demanding 110% of my time, but I did manage to sneak in some time on the car in the last few months. So whats happened:

- Finished the change-over to Volvo 240 front brakes. They are awesome, plenty of braking power, no fade, no boil.
- Added brake cooling to the nose of the car, its working well
- Built a new Subaru SSM-to-CANBUS computer using a much more powerful micro controller, the STM32, rather than Arduino.
- Built a new-to-me junkyard EJ motor, cleaned it all up, added remote oil cooling and STi pan + pickup, larger oil pump too.
- Took the car to the track and blew up the motor, more spun bearings.

New plan: Im done with EJs. Im swapping in a Honda J32 and adapting it to my existing Subaru 5-speed. Kennedy Engineering makes an adapter, its not cheap at $1000, but its cheaper and easier than replacing motors.

The EJ motor is just too temperamental and too fragile to put on a racetrack. Every topic I've read on this motor is littered with excuses: oil weights, bearing sizes, oil pump sizes, oil pick up types, crank oiling design, centrifigal forces at the rod bearings, sub-optimal location of the IAT sensor, tuning, tolerances... and on and on and on. Im not convinced that a solid track-worthy EJ can be built without substantial expertise and cost, where in contrast Honda J motors are ubiquitous, cheap, powerful, and so far seem to come with none of the fragility we're all seeing on the EJ motor.

I've added a pic of the oil pressure sensor data, and I had a super-bright LED on my dash for any oiling alerts, so I don't suspect that oil starvation was the cause of the failure on this motor. It could have been that the engine was injured before we got to the track, thats entirely possible, but for me and for what Im trying to accomplish I can't find the logic in trying over and over again with these motors.

My JDM J32A2 motor is on the way, I'll be cleaning it up and getting it wired through the winter with the intent of running it in 2021. Looking forward to hacking the Honda diagnostics protocol, its K-Line just like the Subaru protocol, so mapping it to CAN-BUS should be a breeze.

I'll also be adding a fuel surge-tank in the coming year, my current tank design isn't any good on the track.

Enjoy the pics!

Modified the struts, and drilled the bolts, so both calipers are safety-wired:


Yellow brakes add 5hp:


Spent a lot of time cleaning this engine: Painted the intake and cooling tank, soda-blasted the turbo housings, wrapped the header. It was a pretty motor...


WRX vs STi oil pans. Modified an STi pick-up for the pan to work with my windage tray too.


Looking tough at Thunderhill:


Anger when the bearings let go, again:


Lap after lap, you can see the oil pressure dropping down down down...

[Cairo94507]

well that sure sucks. Looking forward to the Honda swap. (IMG:style_emoticons/default/beerchug.gif)

[mgp4591]

Are you looking to boost the J32 or get more aggressive with the cam profile for your track attack? Those engines are plentiful and are held in high respect among the Honda crowd... good luck!

[Mueller]

Hey Mat,


Any reason for the smaller J32 instead of the J35 like I have?

I'm going to have to do some more reading about the K-Line, but I like it is ISO 9141 (IMG:style_emoticons/default/smile.gif)

[MichiganMat]

Big update from the MichiganMat garage:
- The J32A2 engine is in and running really really well.
- Added a 71" #BigWang from 9LivesRacing.com
- Upgraded my wheels to 17" Fikse FM10's, 235/255 Nitto's
- Added a front splitter

Headed to Seca tomorrow with NCRC to shake down all the new gear, can't wait to see how it all performs. The car has been running great ever since the J installation, have had a few solid track days with the car without incident (though I did destroy 2 CVs at the last track day due to bolts backing out).

Mostly Im just super proud of how this car has turned out and wanted to share the picks with the forum, thanks for all the support.

[mgp4591]

Great job on seeing you vision come to life! What is up with the exhaust system in the back? A spare muffler on a bike rack??

[krazykonrad]

Great to get an update! There is a safety wiring kit floating out there somewhere for safety wiring CV joints. Well worth the couple of bucks. (IMG:style_emoticons/default/beerchug.gif)

[jd74914]

Let's see some pictures of that new engine install!

[Retroracer]

Great job on seeing you vision come to life! What is up with the exhaust system in the back? A spare muffler on a bike rack??

So Laguna Seca has aggressively enforced track noise limits, which if you exceed will get you black flagged until you get it fixed. There is one spot particularly where the mic is located which is on the RHS of the track; so the guys with loud cars have to get creative with exhaust routing and mufflers, some of which end up a cartoonish aspect, but most of which "exit stage left", to try to direct the SPL thatatway. Matt's solution looks neater than most I've seen!

- Tony