Getting Mad Boost Creep

[Dudewith2DSMs]

I installed the EVOIII16g in my car two days ago. When I took for a test drive it spiked up to 15psi and kept going until i hit fuel cut. I have my boost controller set to the wastegate(10psi). I have a front mount, custom 2.5 inch piping, blow off valve,intake, 3inch cat-back, 2.5 inch test pipe, boost controller, 190 walbro. What can i do to eliminate this spike. Tell me what mods I need besides injectors and a fuel computer to get rid of this Creep

 

[Gooberlog]

I think you either need to take out the race pipe and put in a cat, or install a bigger wastegate flapper. My boost stopped creeping with a high flow cat, but now that the race pipe is back on my car my boost creeps to almost 20psi when set to 16psi and below.

 

[super95awd]

My big16g creeped to 20+ as well with 3" dp and 3" test pipe. I ended up putting in a 34mm flapper, hogging out the wg passage in the o2 housing TONS (was ported before but I went crazy on it), and porting the turbine inlet so there was kind of a step at the wg passage that would divert more air to the wg. Seemed to pretty much cure my problem, it will only creep 1-2 psi now.

 

[Dudewith2DSMs]

I don't have a downpipe yet if i get one will that improve it at all

 

[super95awd]

That will do nothing but make it worse, but you're gonna have to get one obviously.

 

[98eclipseRS]

ya what stated above port the shit out of you o2 housing and get the larger wg flapper. You should look into an external dump that shoudl help alittle also. I need to do some of this shit also I took my mbc off thinking that was the problem but it was just boost spike I hit 21psi on the stock 14b its all bad.

 

[Zex4g63]

I think most everyone is getting creep with this turbo. I see ShapeGSX is getting it too. Shape seems to feel that the 34mm flapper will blow open at higher boost so I have not upgraded mine yet. I think I may just clean up the stock wastegate port over the winter and see where that leads. I already use an external dump so I can tell you that won't fix it. In the mean time it levels off at 25psi so that is what I have been running. No real issues, not detonating and no pulled timing. Egt's looking good so I'll continue to run it that way.

 

[Dudewith2DSMs]

I am looking into getting the 3" 02 eliminator downpipe with external dump from RNR i know people say it is loud but i heard it sounds like crap is this true

 

[Kingdom]

my 14b creeps to 21-22psi. I dont have the boost controller even on. it will hold 10 psi once it hits 5k it will jump to 20+. turbo and mani and 02 housing is all stock 1g. just a 3inch downpipe and catback and no cat.

 

[98eclipseRS]

Originally posted by Kingdom
my 14b creeps to 21-22psi. I dont have the boost controller even on. it will hold 10 psi once it hits 5k it will jump to 20+. turbo and mani and 02 housing is all stock 1g. just a 3inch downpipe and catback and no cat.

Ya im almost the same but I have 2.5" not 3" and i hit like 20 psi at a little over 4.5k. Its really annoying hit fuel cut all the time becuase of it too.

 

[moonstation2000]

i just installed a 3" dp and exhaust. i had boost creep on the 2.5" system and now it's worse of course. i have a very large internal wg, ported 2g exh manifold, o2 dump and my car overtakes the boost controller at about 5k rpm. i'm thinking i might be better off letting the boost creep and working on supplying the extra fuel the car needs.

 

[Dudewith2DSMs]

anyone else

 

[bizzydsm]

I have crazy boost creep too... I have my controller set at 15 psi and it creeps up to 20psi. Ill problebly port my flapper housing and my exaust manifold, and if that doesnt help Ill problebly have to go to a tial external. $$$

 

[Dudewith2DSMs]

Thankx a lot fellows i ordered a external dump 02 housing and am going to have extreme port the wastgate side and get a 34mm flapper and hopefully this will eliminate most of it

 

[RipperXX]

Couldn't you just shove a silancer or something in your tip to incress back pressure on the top end?

That sounds like a good temp fix to me...

 

[rebuilt65]

I have an unported 14b with unported evo mainfold, an unported 2g o2 sensor housing, a 3in pacesetter down pipe into a 2.5 in presilencer and 2.5 in exhaust. I have installed a bleed T in the wastegate line to set boost to 15 psi. I get a quick spike to 17 psi, settles into 15 psi up to 5200 rpm and then creeps to 17 psi. I think my 2.5 in exhaust is keeping the creeping to a minimum. I read in a cuople of places that the 16g, regardless of what type of wastegate, creeps. You can only minimize it at best. I know a couple of guys here that have the same issue. (I always wanted to upgrade to a Hahnracecraft 20G with the bigger exhaust housing and 34mm flapper.) Creeping becomes less of a problem if you have the fuel to compensate.
Regards

 

[rebuilt65]

I think a ported evo o2 sensor housing would help as the wastgate passage is quite large.

 

[JRod]

I run the 16G, but still have the stock O2 and DP. I have gutted the cat and have a 2.5" cat-back. The most boost creep I've ever got was 1-2psi, but quickly levels out. By the way I finally hit fuel cut for the first time ever in this car. It was 38 degrees, running 20 psi on pump gas. Never felt the fuel cut till today, and man does it suck!!!!!