Boost Creep (oldman read this)

[tstkl]

I subtracted 20% and its still hitting fuel cut at about 6000 rpms. The o2 voltage is about .89-.91volts,...

BUT THE PSI IS 20

creeps like its not even set to any psi at all, guess I've got some porting to do.

 

[~laser_craver~]

Well today i actually stumbled across a carbide bit today at work and i grabbed and air tool and finished it correctly. everything is just peachy. the inlet is actually opened up more the chadillacs and the the flapper get to about 85* the entrance to the wg hole is almost gone that how much i took out so im confident that it will fix my problem. well see tomorow as i am waiting on the turbo bolts and i need to port my exhaust manni

 

[oldman]

Ryan, make sure you match the o2 housing to the work you have done on the flapper path. If you're upgrading to a tubular O2, let's hope you didn't take out too much from the turbine side.

 

[~laser_craver~]

I didnt port any out of the outlet near exhaust wheel. All i did was sand paper wheel it a little to smooth it out. The flapper does not hit at all in the o2 housing. Like i said its about 80-85*. Well you saw the pics from ealier thats how far it opens now. The only difference from the last pics and today is that inlet is allot bigger, w/g hole is bigger, and the entrance to the w/g hole is no longer there it has been reduced a whole ton. Id take pics for you but i have it mountedin the car already. Sorry.

 

[~laser_craver~]

I still have boost creep. It spools way frikin faster buut it still creeps. I have boost all the way down so it hold steady at 10psi, then at 4200 it starts to creep and at 5200 in every single gear it hits 14psi and fuelcut. Im frikin pissed, now im going to go weld my cat back in till i get an external or something. What else will help get rid of it?

 

[oldman]

I still have boost creep. It spools way frikin faster buut it still creeps. I have boost all the way down so it hold steady at 10psi, then at 4200 it starts to creep and at 5200 in every single gear it hits 14psi and fuelcut. Im frikin pissed, now im going to go weld my cat back in till i get an external or something. What else will help get rid of it?

Don't freak out, I don't think boost creep will be a problem once you figure out why you're hitting fuel cut as you should be running 15psi anyway.

You said you have leak tested, how much pressure and for how long was the intake tract able to hold? It would be helpful if you can borrow a logger to see what your mafs is at the time of fuel cut. Same questions for tstkl as well.

 

[~laser_craver~]

Should i try messing with the maft a little and see if it creeps more then 14?

 

[oldman]

Should i try messing with the maft a little and see if it creeps more then 14?

I don't feel comfortable telling you to adjust the maft without a logger but if you're hitting fuel cut with an EVO3 at 14psi, there is a a strong possibility that the maf reading is too high like the other person I was helping out two days ago. You also didn't answer my question on the final conditions of the leak test, boost leaks is the number one cause of fuel cut so make sure boost leaks are truly out of the equation.

 

[~laser_craver~]

Absolutely no leaks at all. I might run my happy butt up to Pina and see what they find with it. At this point Im just really frustrated. Im going to put the cat back on this week.

 

[oldman]

Don't give up, you should be focusing on finding out why you're hitting fuel cut.

 

[~laser_craver~]

What kinda boost should I be able to run on stock fuel with my setup? Could this all be holding back how my car performs? Well I mean for the part it does perform . I think Im just gonna put the cat back on for now and when I get a chance Im going to go to kent and have Pina throw the wideband on it. When I have them do that what is it I should be looking for to try and figure out why my car is doing what its doing?

 

[~laser_craver~]

PS Oldman when I go and replace my timing belt balance shaft elmination and new water pump gasket I will take the turbing housing off again because I want to port manifold anywyas. And I will try to port the turbo some more. So watch for this thread being brought back from the dead.

 

[oldman]

Good luck.

 

[oldman]

Ryan, check out this other thread on the same project which just ended with a complete success. Compare what he did to your own, if it worked for him, there is no reason why it wouldn't work for you.

 

[~laser_craver~]

After porting I notiuced that the creep wasnt as bad but it is definately still there.

 

[~laser_craver~]

Ok oldman i have done a little more work in hopes of elminating my boost creep. First I ported the manni just because i had it off again. And second I followed a tech aarticle on this site showing how to make and external dump out of your stock o2 housing. So hopefully that will help a little with the boost creep. If not then i guess i will port some more out of the turbo. From the port work i did early on it did help the creep problem but it did not totally elminate it.

EDIT: I will tell you if it still creeps after doing that to my o2 tomorow afternoon. As it is late and i leave near cranky ass old people who ###### dont want to here the external dump at 9 pm.

 

[~laser_craver~]

And here is a link to the tech article i followed.

http://dsmtuners.com/forums/showthread.php?t=63449

 

[~laser_craver~]

The o2 dump didnt change a darn thing except the loudness factor.... And i noticed at idle the wastegate leaks a little thru the dump tube.... Im ###### going to throw int he towel and go exteranl on the o2.... im tired of the hassle. If anyone has anything i need for my external setup ie wg dumptube o2 housings flanges etc. pm me ill buy em from ya