Dark_Teg

I am wondering if you are making 22 psi at the turbo but have a massive leak and only getting 12 psi to the motor?

Turbo-LS

iTrader: (4)

We need a like button on HT. who's with me ?

LightningTeg

Agreed. For real street to come out and say he needs better cams kind of blows my mind. Pretty basic **** here.

TheShodan

iTrader: (14)

I'm thinking that there is one somewhere as well. Definitely not from the boost reference source being at the intake manifold vs. the compressor cover. That's in another thread and has been continually beaten to death.. In this case, its not relevant for the symptoms of his issue here.

But he certainly doesn't need to change camshafts for this.

Geis

Trust me I say the same thing every time I'm here, the one major thing I like about TI a lot better actually.

blackeg

i was going to mention the inline pro manifold but i had a feeling he wasnt running one. we all know its a great performer. the spa is good too, i tuned a built gsr with one and a mid sized precision turbo and it was a great combo.

however, something like a tubular log, or a rev hard with a turbo that big id be worried about reversion and excessive backpressure. id be more worried with larger cams but in this case the gsr cams are making that situation not as bad as it could be but still im sure its a contributing factor.

its not the cams, id still say boost leak is the largest contributing factor.

TheShodan

iTrader: (14)

Leak is the biggest factor..type of manifold I'd minimal at best. You'd only suspect it with an EGT reading, really.

Look to the manifold dead last. But here, it's not the case with a large leak like this sounds..

Leak fix first, the see about parts replacement

roll8221

Going to check.for boost leak in the tomorrow a.m. took it out for a run today and think i lost boost almost completely. A/f ratio went so lean it wouldnt read part of the time too... have to rig up some sort of cap with a nipple and pressurize it...think i saw one made out of pvc maybe... thanks again everyone... didnt expect to get this much help... def appreciated.

Turbo-LS

iTrader: (4)

I can set you up with a emap canister and sensor if all else fails

TravisBiggie

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phaphon

so having a log manifold that is not efficient enough for your build can cause higher egt?

TheShodan

iTrader: (14)

Yes. given the right circumstances (like everything else, of course)

roll8221

I have recently installed a oil catch can with breathers to decrease my crank case pressure. After installing though, I noticed it doesn't have quite as much pull when accelerating and a little bit into the drive, I noticed my air fuel ratio was much higher (lean I think) than usual, sometimes not even registering on my gauge... Ive tried to do some reading on the subject but not a lot of information particular to my situation. I also checked for leaks, found a couple very small ones, just enough to whistle and make some bubbles, will fix today. Any thoughts on the new issue?

turbohatch96y7

iTrader: (15)

I suggest you stop driving like brian o connor and have someone who knows what they are actually doing take over from here

If you dont know what is lean or rich then that motor isnt going to last very long

Dark_Teg

How are you finding the leaks? Have you done a compression/leak-down test?

roll8221

Ive done a leak test on the charge pipe/intake but not the engine itself. I have stopped driving it, until i find out the most current issue, but other than that the tuner said it was safe to drive

Dark_Teg

Based upon this I am going to have to say.....NOT SAFE!

TheShodan

iTrader: (14)

that, and because the leak is causing the car to get closer into vacuum his management and gauge are not reading as rich as it needs to be. Its a direct correlation.

That's like having someone panic about their gauge reading 15.2AFR for a split second after letting off of the accelerator suddenly and coasting while driving on the highway. Its "lean" because he's not running any fuel to the engine while coasting to an exit ramp. Doesn't mean its so lean that it'll detonate.

He needs a boost leak tester, not just some soap and water to find "bubbles" for the leak.

roll8221

I used a 2.5 inch coupler with a can on one end and the other end connected to the charge pipe right off of the cold side of the turbo. I put a tire valve stem in the end of the can, hooked a pressure regulator behind an air gauge to 20 psi and pressurized the system. found a leak where a sensor is welded into the charge pipe. I used the soapy water to figure out exactly where the leak was coming from because it was hard to locate by ear.

TheShodan

iTrader: (14)

Good start.. there's more around though, I betcha that for the issues you're facing now.

roll8221

I also noticed after some time, some very fine bubbles were coming through the gasket between the throttle body and intake and the bolts securing it but seemed almost insignificant. could a leak that small be a problem?

KevinEF7

While those leaks may not be significant, they probably skewed the results of your test, you should disconnect the charge pipe at the throttle body and have that end plugged.

When you pressurize the system with both ends sealed (coupler off turbo/throttle body) your air pressure should hold steady.

A small pinhole leak isnt going to cause this huge boost loss some seem to think your having, to lose 10+psi its going to be a substantial leak/sliced coupler

LightningTeg

Hell I forgot to cap off the 1/8NPT plug on the compressor housing on my GT28 once and I didn noticed it until I was trapping 10mph slower than normal and AFR's were all over the place.

wantboost

iTrader: (2)

It doesn't take a very large air leak to cause problems. You have to remember that injectors are open for only milliseconds at a time, it doesn't take much to throw off the entire tune.

ATYPR

Can you post a pic of your wastegate dump?? It looks like you're getting exhaust contamination.