Hey guys.

Since the beginning of summer, I feel like something is wrong with my Evo.

Last year, 1 week after I got it I snapped a 1.8' 0-60 and I barely knew how to launch the car... I ended up doing 13.8 @ 99 mph which is respectable for a first time at the track with an AWD and I used the slip & drop technique which, I think, is the best way to launch this car.

This year though, I can't get under 2.0-2.1 0-60s and over 95mph trap speed and that even after multiple attempts (not during the same night). I feel like when I'm launching the clutch is slipping too much, it doesn't grip like it used to. I used to get very little wheel spin when I nailed it right but now it's not putting down the power like it used to and I can smell a little clutch after I park the car but really not that bad.

- I tried putting the car in 5th at slow speed and punching it but the clutch doesn't slip.
- Boost gauge indicates 19psi peak tapering to 15-16 right after till redline.
- The whole car is bone bone stock except for a boost gauge and 39 000 miles.
- I never dropped the clutch from a stand still.

Is my clutch starting to go?
Do I have a boost leak?

My friends swapped GC8 subie spanked me last night and I always used to beat him at the track... grrr.

 

Stock clutch? Sounds like she may be on her way out

 

boost leak?

 

This alone leads me to believe that you have a boost leak. A sudden, drastic change in performance doesn't just come about for no reason.

Although you hit 19psi and taper to 15psi or whatever, that doesn't rule out a boost leak and the effects of one on the load/timing tables of the ECU.

Invest in an air compressor and a boost leak tester if you haven't already, it'll save you a ton of time, pain and frustration. It was honestly my first "mod"

 

When you say you smell clutch when you park it is that after racing or just normal driving?

 

Clutch is probably slipping when heated up. Also most likely you have a boost leak if you havent checked lately. Id do a simple tune up if you havent (new plugs, boost leak, fluid changes, filter changes etc.) Im sure you'll find a few things.

 

Yeah it might be a combination of both.

I punched it a couple of times last night and I have very irregular boost. Sometimes it'll peak to 20, sometimes to 18 and it will taper anywhere from 16 to 18 psi. It's pretty inconsistent. I think this pretty much answers my question + I never did a boost leak test on the car since I got it so maybe I'll find a couple of suprises!

And for the clutch. It's possible that it only slips under hard conditions? Like it could be on its way out even if it still grips on the streets?
I only smell clutch for a couple of minutes after I raced it, nothing really alarming it's just... noticeable.

I don't know about doing the boost leak test myself, I'm kind of uncomfortable working on the car. I baby it too much and don't wanna break anything..


Edit: Next time I'll go for a ride I'll try and see how much boost I'm building with the factory LC @ 5000 rpm.