boost / fuel problems with new 16G

[my98gsx]

Yesterday i put in a 16G on my car. I talked to Slowboyracing, and DSMparts, and they said that i could put it on with my stock injectors as long as i keep the boost between 12-14psi. When i put the turbo in it would make over 15lbs instantly... ( that was with my boost cont all the way down ) and it kept hitting fuel cut. I took the waste gate actuator off and lowerd it and then last night i was right arround 15 under a strong pull ( 17 with creep ) and still the car feels really boggy. This morning i took it off again and lowered it all the way, now when driving it its like 3,000 nothing... 3,50 nothing... 4,000 nothing, and arround 4,5000 WACK it spikes like 15lbs and fuel cut kicks in again... no matter what i do i cant get the boost down and cant stop it from hitting fuel cut even thought its running rich... anyone have any ideas?

Just to let everyone know... im running a walbro 255, a fuel pressure regulator, An SAFCII, and a larger fuel rail ( i know the rail does nothing ).. all im missing is injectors but i dont feel that that is the problem at this point...

 

[swerv600]

after you installed the turbo did you do a Boost Leak test?

 

[my98gsx]

i dont know what a boost leak test is but when i checked my wastegate "flapper" i guess you would call it, its VERY stiff and sticks not like my T25 or 14B did, this is like hard to move i dont know if its just because its brand new or what but it feels funny...

 

[swerv600]

Testing for boost leaks is probably the most important thing you can do to your car. You should do a search and you would be able to find out the endless threads on boost leaks.

What do you mean the flapper is stiff or sticks? did you take it off the wastegate?

 

[oldman]

1. EVO III 16G are pretty much guarrentee to creep, both vendors should have warn you about that and you should have ported the turbo properly like this before you install the turbo.

2. You shouldn't be hitting fuel cut at 15-16psi, perform a boost leak test and fix all leaks.

 

[swerv600]

This should help:

1.port the turbo
2.Boost leak test (just search)
3. keep boost down until you get injectors
4.Tune Tune Tune

 

[MyBeatGSX]

All the porting in the world isn't going to get that turbo to hold below 16psi.

There's definately something wrong with fuel cut at that boost, like everyone said, check for leaks! And its time for some fuel system upgrades, because like I said, that turbo isn't going to hold low boost. I have mine ported pretty well and an external dump O2 housing and it still creeps about 2psi by redline (set at 19psi, creep to 21psi).

 

[oldman]

All the porting in the world isn't going to get that turbo to hold below 16psi.

Speak for yourself. Although not a walk in the park, there are plenty of 14psi to redline examples.

 

[MyBeatGSX]

Well let's be reasonable. Those people must have welded in a custom funnel to force all the exhaust out the wastegate hole.

Seriously though oldman. Don't you think porting that extreme is crossing the line of hurting turbine flow. That wastegate hole is shrouded for a reason. Making it completely exposed to the exhaust flow is just making something for the air to catch on and get turbulet over. There comes a point when you've taken off so much you've completely changed the housing's funnel shape.

 

[WFO-TSi]

i dont know what a boost leak test is but when i checked my wastegate "flapper" i guess you would call it, its VERY stiff and sticks not like my T25 or 14B did, this is like hard to move i dont know if its just because its brand new or what but it feels funny...

It sounds odd to me that you have such a long delay in spool time. Sounds like an exhaust leak that is pre-turbo or else your wastegate is stuck open. I would say pop the hood and remove the heat shields (if you have them installed) and with the car VERY COLD start it up and feel/ listen for exhaust leaks around the turbo to exhaust manifold seal.

You can test wastgate operation with the turbo installed. I just take a bicycle tire pump with the valve stem fitting removed. I put the rubber hose from the pump on the wastgate fitting and pump it up a few times. You should see the wastegate arm move. Once it is open quickly pull the hose off the actuator and you should see the arm quickly retract and shut the wastegate.

I hope that helps.

 

[oldman]

Seriously though oldman. Don't you think porting that extreme is crossing the line of hurting turbine flow. That wastegate hole is shrouded for a reason. Making it completely exposed to the exhaust flow is just making something for the air to catch on and get turbulet over. There comes a point when you've taken off so much you've completely changed the housing's funnel shape.

Definitely there will be more turbulence from the port job, nothing is free.

 

[2gGSX]

.. all im missing is injectors but i dont feel that that is the problem at this point...

I think that would be the answer to your problems actually. Before putting my Evo III on I always read about the creep everyone got and what not, so instead of this "porting" nonsense (kidding) I upgraded the fuel system and IC to let the turbo run whatever it wanted to. Probably just legitimizing spending a lot of money to myself, but it works.

 

[my98gsx]

i think i fixed the problem.... belive it or not i thought the car was running out of fuel... in a last min attempt it turned my AFC down to +/-0 and the car runs great.. i think that stupid 255lph pump was putting out too much fuel... im still running really rich and i think i can even turn down the fuel a little more but im going to be careful about it... im going to the track this wendsday night for test and tune i hope my time goes down alot with the
16G on it.. thanks for all the help.

 

[Talesin]

PLEASE tell me that you aren't running a Wally 255 without a proper AFPR (and not one of those B&M POS). If you're still on the stock FPR, it'll be overrun pretty damn easy, and make tuning unstable/erratic.

 

[MyBeatGSX]

If you still have stock injectors then the AFC should be all zeroed out anyway. That was probably your problem right there.

 

[tha buziness]

yes i am running a walbro 255 with a B&M fpr.... i never saw a problem wuth ut untill i put the bigger fuel pump in it... now i think it may be the problem because i am dumping alot of fuel... now somone said that if i dont have bigger injectors the SAFC should be at 0.... well fooling arround with it even with the stock injectors i have knowticed a difference.. the thing that makes me think that im dumping way way too much fuel is because the lower i set the SAFC the better the car runs... right now i have it in the negitive numbers and its running alot better ( and when im getting on the car its still very rich on my
AF gauge...) im thinking that maybe it would have been better not to have touched the fuel pump in the first place... i never had a problem prior to putting it in but everyone said that the pump sucks in the car from the factory and that it was cheep insurence to jusyt have the larger one in.... would another FPR hel me out? my friend has a rising rate one that he got a while ago that he said he would sell me cheep so im going to go try that one out.

 

[my98gsx]

^^^^^^ the above message under "the buzness" was posted by me i was under my friends name....

 

[exile]

You're not suppose to use a B&M FPR.

Try: this.

(Here you can find one of the many posts that describe why the B&M is not for you. In summary you can still overflow your stock FPR and you can only raise pressure.)