ImperiousRex's Greddy Turbocharged BRZ

[ImperiousRex]

Originally Posted by botbs

Hi there,

What's the offset on your gold RPF1? +35 or +45 ?

Thanks!

+45 (Note this offset required that I get spacers for my front wheels to fit around the BBK)

[botbs]

Originally Posted by ImperiousRex

+45 (Note this offset required that I get spacers for my front wheels to fit around the BBK)

Would 5mm spacer work? I currently have the same offset wheel RPF1 17x9 +45 but silver. I am thinking of getting same BBK.


Million Thanks !

[ImperiousRex]

Originally Posted by botbs

Would 5mm spacer work? I currently have the same offset wheel RPF1 17x9 +45 but silver. I am thinking of getting same BBK.


Million Thanks !

I would recommend 15mm but no lower than 10mm. 5mm would cut it very close and would most likely result in contact at some point between the wheel and BBK.

Evasive recommended the 20mm for me mainly because they know how often my car is tracked and the extra clearance is just a precaution.

[ayau]

Originally Posted by ImperiousRex

I would recommend 15mm but no lower than 10mm. 5mm would cut it very close and would most likely result in contact at some point between the wheel and BBK.

Evasive recommended the 20mm for me mainly because they know how often my car is tracked and the extra clearance is just a precaution.

I'm guessing you replaced the OEM studs with extended ones?

[ImperiousRex]

Originally Posted by ayau

I'm guessing you replaced the OEM studs with extended ones?

Yes. I originally got a bolt on spacer solution to make a track event just after I got the BBK but eventually switched to ARP extended studs to reduce the possible points of failure.

[NJA]

very impressive build!

[diss7]

Great build. Just read the lot!

[CajunFRS]

I just looked through this thread. Time to do it all over again!

[swift996]

@ImperiousRex nice build. By any chance do you have some pics of the brake ducting routing and backing plates? I've got a few parts and might pick up the APR backing plates to finish off my kit.

[Acree]

@ImperiousRex

Maybe you should look into something like this for your bumper:

http://www.ft86club.com/forums/showthread.php?p=1348751

[ImperiousRex]

Originally Posted by swift996

@ImperiousRex nice build. By any chance do you have some pics of the brake ducting routing and backing plates? I've got a few parts and might pick up the APR backing plates to finish off my kit.

Heya @swift996 - so sorry for the delay on this. Been super swamped with work and track events for the last few months. But here's the lowdown on my brake ducting (don't mind all the dirt and dust >.<). After the intial install, I found that my wheel/tire setup was rubbing on the APR 3" hosing that comes with the kit and after my first track event with the hosing, there were some gaping holes :P So Evasive got me some hose reducers and we switched to a 2" hosing up to the backing plates. Here's how the routing is now:







If you have any other questions, feel free to hit me up.

[ImperiousRex]

Originally Posted by Acree

@ImperiousRex

Maybe you should look into something like this for your bumper:

http://www.ft86club.com/forums/showthread.php?p=1348751

Yes... yes I should...

[ImperiousRex]

Hi guys, so this update is loooooong overdue and I apologize to those of you who regularly follow the car. But a lack of updates doesn't mean the car has been sitting around doing nothing In fact since my last update the car has been to another 10+ track events and time attack events and the turbo has been through 20+ track days at this point. This equates to a lot of development insights that I'm happy to share with you today (both good and bad).

First of all, I am still running on the original engine and I want to credit @Evasive Motorsports for a solid tune that I wanted geared for hard track days. While it doesn't set any dyno queen numbers for epeen records, it's been very reliable up to this point. We haven't had any catastrophic incidents despite running it quite hard to multiple track records for the platform. However, that's not to say we haven't had any issues.

The DI seal issue reared its ugly head and I had all 4 seals replaced early this year and I've also had to replace the cylinder 1 ignition coil. While I had early signs of both starting to go before the turbo ever went on (i.e. misfire and ignition coil CELs) they both gave up after the turbo was on so neither was covered by warranty as expected.

Beyond those two problems, the main issue we've been tackling is adequately cooling the car. As many of you with turbo experience might know, the front mount for a turbo is not ideal for avoiding heat soak. @CSG Mike had run the car for multiple events and noticed that in the straights the car wouldn't pull much harder than a stock S2K after a couple sessions despite the initial dyno from Evasive showing much more power than a stock S2K would. So we took the car to a couple other dynos and had some testing done. First up, we have dyno runs on a Dynapak dyno at Church Automotive on 100 octane.



As you can see Dynapaks read quite high in comparison to other dynos but this is roughly what we expected compared to Evasive's mustang dyno. We didn't see a parasitic loss here so at our next stop with European Auto Source's Dynojet we secured time for multiple runs back to back with a closed hood and a single fan to simulate the car in motion:



So what you see here is the power on the first run when everything was cool and on a DynoJet vs. power after 6 runs at high rpm's. The whp in cool conditions again corroborate the Evasive numbers but the 40whp loss after 6 runs was eye opening. On track we suspect the car is losing even more power after multiple sessions and the main culprit appears to be the intake ambient temperature (IAT). As you can see there's a direct correlation in this graph:



Now keep in mind this is probably something that daily driven cars will never really experience. This type of heat soak is from sustained high RPMs for extended periods of time. On track this will be up to 20-25mins of 5-7k RPMs during the entire session. (Although in hot summer months this can happen more naturally.)

Another hint that the engine bay was getting too hot was what happened to my stock fans...



We're not 100% sure if the melting caused the fans to stop or if the fans blew a fuse and the lack of pulled air caused the fans to melt. But either way things were getting too hot in there >.< The stock fans are wired across the center of the fans and the proximity to the turbo exhaust manifold may have caused them to melt as well. So as a result, we decided to upgrade to higher flow Spal fans, a radiator shroud from @Carolina Dyno and rewiring the fans along the bottom of the engine bay rather than across the center.





Despite having to use the lower profile versions of these fans to fit in with the turbo kit, simply put they are incredible. They can drop coolant temps 15 degrees in about 10 seconds and if you have a gauge to monitor the temps, it's fascinating to see how quickly they work.

Sadly even with the fan upgrades the Robispec radiator solution has failed me twice now. The first one developed a leak earlier this year after about 4 months of tracking and after taking it back to get checked out Robi suspected that there was electrolysis going on in the radiator which caused the leak. So we replaced it and another 4 months later, the 2nd radiator has fully cracked. Granted the ambient temps have been gradually rising in these 4 months but it would appear the radiator isn't sufficient to handle the temps generated by this turbo kit.

So that brings us to today. I'm now looking at a Koyo radiator and Greddy oil cooler solution and we should have some data to look over in the coming months. Robi may still be right about the electrolysis though and I'm going to get my electric system diagnosed soon to see if we have anything excessively drawing power.

[ImperiousRex]

Not everything has been bad news though! The car has seen a few more upgrades in the past few months. First off, I had all the intake piping for the turbo kit ceramic coated to help keep IAT's down.



I've also replaced the ACT Lightweight Street Clutch kit with an Exedy Stage II Cerametallic Clutch Kit. The ACT was ok but the engagement point was really close to the floor and had some engagement issues on track. The Exedy in comparison is just grippier and has a higher engagement point and on track it's been very solid so far.







And lastly my favorite upgrade in the past few months is the addition of a Cusco Type RS Limited Slip Differential:



The LSD was configured by @CSG Mike for 1.5 way and 80% engagement I believe. Ask him for any questions on the specifics. My experience with it so far is that I love the additional grip mid corner and how it works with the Sport Traction Control system. I drive the car with both TC off and STC on and my main complaint with the STC is that in a high speed sweeper, the STC tends to cut power when I want it the most. With the LSD, it's far less intrusive and is basically doing what I mainly turn it on for - which is keeping me on track when the back end snaps. While pricey I would highly recommend this LSD over almost any other mod that I have (the JRZ coilovers being the exception).

At this point I think I'm good with the car for the next few months. The only other mod I'm looking at is upgraded rear axles but that's more for necessity than anything performance related.

Here's how the car looks at this point (the stickers have changed a few times since the last update):





Thanks to everyone who follow the car and I'll try to keep the journal updated more regularly!