Hey guys. Finally bought the car I always knew I wanted lol. It's an 05 Evo 8 GSR. Has a few mods, I wanted one with out any but yeah right. On the plus side, from what I can tell, the current mods are not anything crappy, but If anyone cares to read my list and tell me their opinions, that'd be cool. I'm used to my turbo 420a that I built from the ground up so I'm still a little new to evos. My mods are as follows:

-3'' down pipe
-3'' cat delete pipe
-sound performance boost activated exhaust cutout
-quartermaster clutch and flywheel
-perrin complete intake system
-fabbed 02 housing
-synapse diverter valve(dumps into intake)
-arp head studs(according 2 the parts receipt i have, no way of knowing for SURE yet)
-buschur upper i/c pipe
-forge manual boost controller
-it says turbo back exhaust but i swear the catback looks stock
-buschur ported exhaust manifold, looks stock. maybe buschur ports your stock one for you?
-walbro pump
-looks like aftermarket injectors
-spoolin up individual coils
-larger intercooler


I don't know if some of these things are still on or have ever been taken back off and returned to stock. Only had the car three weeks and haven't really had time to look for everything. I do know that it had 74k miles on it, and it does drive very good.

One problem I notice...and I have done hours of research, but can't find anything information similar to my problem. I've noticed if I hold the accelerator half way down, it'll eventually build full boost and hold it right there, feels great. But when I continue with my foot into WOT it tapers all the way back down to like 8...i've seen where some people have taper problems with 1 or 2 psi but not that much! I really feel like somebody out there has an idea about what it could be. Until I hear back from you guys, i'm going to continue to diagnose. Thanks for reading.

 

oem turbo will taper, mine tapers from 24 to 21 by redline.
whats your peak boost? theres something wrong if you're tapering down to 8 psi....

 

the fact that it has a sp racing cutout would pretty much indicate that the cat back is stock. sounds like you have a boost leak. btw, if you ever decide to go with a normal cat back and remove the SP cutout, i will buy it from you

 

I was told by the dealership it will boost up to 23, but so far i've only seen it hit 19ish, just under 20. So i'm still curious as to the purpose of the cutout, I see them for sale on the internet but I don't see much info like pro's or con's of having one.

Yeah something is def. not right...I'm going to find a way to do a boost leak test and see what comes up I guess. OTHER than that issue, I love the car.

 

I say boost leak test and fix an leaks if you find them. And if it were my car I would do some logs to check out the tune on the car. I assume its tuned and they didnt just mess with the MBC?

 

Judging by how good of shape the car is in, and also by how, i'm assuming and from what i've heard, how decently nice the parts are, i'm thinking the previous owner would have had it tuned. See I built my last car, an eclipse with a 420a, hahn turbo system, and megasquirt tuning. I'm new to the world of tuning evo's for sure. I'm GREEN! But anyways, I'm going to do a lot of reading up and try to find some answers to my questions, like whats the best way to check your current tune with a laptop, is it better to flash the stock computer, or get some sort of after market tuning software, taking into consideration that ill prob keep the bottom end stock for the forseeable future...do I need aftermarket gear? OR can my stock comp. just handle everything with a nice dyno tune...

Things like this are on my mind at the moment, if anyone cares to share some sage advice, why that'd be lovely!

 

While aligning my car the other day I noticed next to the intercooler was a black box which I could barely make out the lettering "electronic boost controller"....I think it said Perrin on the side....what I don't understand is if there is an EBC then why is there no control for it in my cabin....don't all EBC's come with a unit which goes inside the car and allows you to raise or lower boost?
It's running a couple vac lines, and some wiring. Didn't really go too far looking as I was using my buddys shop to do my new tires and alignment.

 

I also have the SP exhaust cutout. I also use it with the stock cat back, but it can be done with whatever exhaust you want. It's purpose is to by pass any restrictions in the exhaust from wherever it's located. Mine is located on the DP. At WOT it's like not having a catback at all.

I'd assume that it has a tune too. However, I've tuned a fair number of cars with bolt ons with the stock tune still on it. Either take it to a tuner or use a Tactrix cable, EvoScan to log and EcuFlash and send the rom and logs to a remote tuner and see what you have on there. I've also seen a fair number of tuned Roms that have the knock light disabled. So you'd never know your knocking unless you logged it.

 

It is controlled by the ECU. That leads me to believe it has been tuned. Part of your problems may be the way the EBC is tuned or it's malfunctioning.

 

I also came from the eclipse world so I had to learn the differences haha. The Evo computer can take a tune stock =]

 

+1

I just tuned a stock IX with stock tune and it was running 10 AFR at WOT!

 

I'm about to harass google for a few hours

 

It still boggles me why it will hold nearly 20lbs at partial throttle, but as soon as I go WOT it kills it...drops way down...how can it hold the 20 pounds up until a certain point in your throttle position then it changes? Whats the difference? That should be a clue. Unless of course, the tune is bad some how some way

 

Have you completed a boost leak test yet?

 

I'm planning on it this week on my days off. I'll post my findings...

Ok so before I search through 2 dozen "How to boost leak test an evo 8" threads, can someone just share the best link for me to use? That'd be cool. Really cool.