I'm just curious to see the results. Those who purchased an AP and checked for leaks like cobb reccomended what did you find? And for those who don't know about the service bulletin here it is:
http://www.cobbtuning.com/info/?ID=3481

 

bump! i'm waiting for mine to arrive sometime next week. Any dealers/installers check for leaks?

 

You should do leak tests regularly, especially if you have replaced/removed any part of your intake tract.

I'll see if I can find where I got my $14 tester (gauge included but you need a coupler)

 

I don't want to post a direct link since they are not a vendor, but check for boostpro. You should find it pretty easily.
Cheap and it works good. I recommend getting it with the gauge to simplify your life.

 

thanks.... expecting the ap to arrive tomorrow. Probably going to check and install this weekend.

 

That service bulletin was a direct result of the experiences with my car giving way to us closely investigating all other Evos that have made it in. More often than not, the car has a boost leak. It varies between the bypass valve, injector seals, and throttle body seals, but it is VERY regular to see boost leaks.

A boost leak should be worked into your normal maintenance schedule, being done about every 5k miles.

My method for checking leaks involves a piece of silicone hose, a length of flared aluminum tubing that has been capped off, and a tapped in schraeder valve. The home depot elbow is only good up to about 20psi before it will invariably blow out of the hose.

-Jon

 

we agree with doing regular boost leak tests. We're a COBB Dealer and ProTuner. Our test EVO 9 did not exhibit any leaks, but 1 out of 3 EVOs suffers from leaks (from our own experience). A leak will throw off your AFR, sometimes your boost, add in lag, and a bunch of other bad things.

Stephen

 

Sorry for my ignorance but im trying to understand exactly where you would connect the test devise. This is what Cobb is saying.

"Simply disconnect the first rubber intercooler coupler from the turbo J-pipe outlet and insert the test device into the coupler"

Is this the hot pipe side? Also which first coupler, the one connecting to the intercooler or the turbo? Again sorry for my ignorance just trying to understand.

 

The hose I use for leak testing is the turbo outlet hose. This is the hose that goes from the turbo to the intercooler on the passenger side.

Testing at this point allows the maximum amount of piping to be pressurized for leak testing.

-Jon

 

We have updated this Service Bulletin to v1.01. The latest versions can be accessed from the various EVO Map Download pages:

Download link for 2003 EVO8
Download link for 2004 EVO8
Download link for 2005 EVO8
Download link for 2006 EVO9

Take care,
Christian.

 

Christian--

so unless we pressure test the system to around 20-22psi we probably aren't going to know if there truly are boost leaks?

 

Which is better, test from the turbo inlet like i've seen or test from the j pipe on the hot side like Cobb says to do????

 

I would suggest you test the car for the conditions it is going to see. I usually pressure test the system to ~2psi above what you boost targets are. If you boost target is 20psiG, then pressure test to 22psi.
You can test on either. Our testing assumes that your compressor housing does not have any leaks. I would try to pressurize as much of the intercooler piping as you can. Inserting the Test Equipment into the rubber I/C pipe that attaches to the J-pipe is how we performed our tests, but you can also pressurize at the compressor inlet if you would like. Testing from the compressor inlet is more thorough IMO.

Take care,
Christian.

 

DeeezNuuuuts83- Their high flow race cat version will sound nearly identical. If we were to video tape it you would not be able to tell a difference. The cat will quiet things down a pinch (and I mean a pinch) more at cruise and idle. WOT should sound nearly the same. Here is some more helpful info direct from COBB:
COBB DP, COBB Catless Test Pipe, COBB Cat Back

idle - 83dB
SAE - 98dB

COBB DP, COBB high flow Catted Test Pipe, COBB Cat back

idle 80dB
SAE 94dB

Help save the earth and we'll throw you free shipping on both your AP and your EVO Turbo Back Catted. I just read Rob's reply to you after typing this out regarding dB, LOL. Sorry for the redundancy. Honestly, you would not know an audible difference between the 2 unless you had them side by side in person. COBBs high flow cats are amazing to say the least!

CPA5- I'll have more for you on this later today. Short term + Long term fuel trim should = 0 (or close to zero). This number is thrown off when people change out intakes (as is the case with subarus, but I believe this carries over to Mitsu the same).

TheEvolutioner- agreed, that is a popular thing for our Subaru AP customers. Only down fall is peak summer time, I would hid the AP away to avoid extreme heats.

Stephen

 

no leaks in mine car runs smoothly on stage 1, now i have to wait for my DP to come in for Stage 2.