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Turbo Boost Creep Creeping T25 14B 16G [Merged]

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So I'm having real bad boost creep on my evo3 and down the road I want to run 20+ psi... Now my question is should I just flash the ecu and set the boost higher till no more creep or spend the money on a dsmlink (which I'm leaning towards) that way I have a data logger but if I can spend less money on a flash and still be good I'm gonna do that.
 
So I'm having real bad boost creep on my evo3 and down the road I want to run 20+ psi... Now my question is should I just flash the ecu and set the boost higher till no more creep or spend the money on a dsmlink (which I'm leaning towards) that way I have a data logger but if I can spend less money on a flash and still be good I'm gonna do that.

if you get dsm link thats is great but it still wont fix the problem because once you start running more boost the creeping gets worst so if i was you get the creeping fixed first then dsm link :thumb:
 
if you get dsm link thats is great but it still wont fix the problem because once you start running more boost the creeping gets worst so if i was you get the creeping fixed first then dsm link :thumb:
This isn't entirely true, ECMLink won't fix boost creep but the more boost you run doesn't make boost creep worse.

You need to have a fuel system that can support your turbo setup before you crank up the boost, then a way to tune the bigger injectors. Until you upgrade your fuel system and have a way to tune the car you need to keep boost pressure down. The only way to prevent boost creep is by creating a restriction in your exhaust system, install the stock dp/cat and you should get boost control back. Then, once you get those supporting mods, you can open up the exhaust and kick up the boost and start tuning it.

:dsm:
 
I have everything all ready for my fuel system. I have a 255 and a afpr installed and some 750s waiting to b thrown in. I'm just wondering for a tuning devise what would be better for me cause I'd like to flash to save the money but I'm afraid cause its not really a logger so I can't keep track of what my cars doing
 
I have DSMlink and highly recommend it. I highly doubt it'll help with boost creep though. A bigger, better flowing wastegate is needed to fix that unless I'm missing something in your question. Look for threads on turbo porting for better wastegate flow.
 
If you're going to boost 20+psi you'll want to keep an eye on knock. DSMlink does that. I have mine set to turn on the CEL when timing is retarded by knock so I know to back off the throttle when I'm not logging. DSMlink helped me determine when I got a bad tank of gas once and the amount of knock jumped way up.
 
im running a 14b w/ j pipe and all hard piping to stk smic 2.5" o2 housing with 8" wastegate dump and free flowing 2.5" turbo back exhaust (and egr delete) on a 2ga 7 bolt. installed a new hbc and i have it set to "off" (if there is such a setting) and i boost 12 psi most of the time unless im wot and around 5k rpms then it spikes to 20 psi and i fuel cut. im going to try setting the boost cont higher but i have a feeling im still going to spike at 20 psi..... i think my only choice is an external wastgate and a new exhaust manifold. also i assume the size of the wg flapper is oem for a 14b....any advice would help me too;)
 
Lets get this out there first. Im not a newb. Im not lazy either. I have searched and seen what has been done on this known issue on a big 16g. Im needing to know where I should go next here. What I've done so far to keep the boost creep down is
Porting- I had the hot side off and ported it as Ive seen done in other posts. Entryway all cone shaped, wg in and out, stock O2 Housing ported out.
WGA- Today I installed a Garett wastegate actuator so the wastegate opens a full 90.
Results...Still creeps like a mofo :banghead:
If I unhook the WGA and run it that way it will still literally build (a laggy)15lbs of boost by 6k rpms! This seems pretty ridiculous... Now I am still on the stock flapper size... not even the 34mm. and I didnt remove any material from the seat... Just rounded everything off. So I'd imagine this would be the next step. Can you remove a bit of material from the WG flapper seat and make a bigger passage but have it still seal?
Also in terms of future plans I have a bigger fuel pump coming, and 850 injectors on my list, plan on running 20 plus boost, So not looking for super low boost numbers just want it to hold solid and run where I set it at. Especially with my stock 450s still on.
 
Good luck, I still have creep issues on my Evo III with a ported WG passage w/external WG setup on a MAP tubular O2 housing with atmospheric dump. Did I mention that the cat-back is still OEM!!! From the O2 housing it goes to a 3" megan DP to a custom 3" cutout, but the cutout has remained closed. And then it is reduced down and fit to the stock cat back....and it still creeps.

Started to think that I either have to port out a ridicules amount for the WG port on the turbine housing or just figure out a way to live with it...which it makes tuning much harder.
 
My Radiator fan was preventing my wastegate from opening all the way once. just a thought. and unless you running close to the max of the turbo early in the rpm range than it has to be something to do with the wastegate. when wastegate is swapped from turbo to turbo especialy the unadjustable ones are prone to being a small amount off or diffrent ie. slightly open or too tightly closed at 0 boost so if its being held tight at no boost it wont open as far when it needs to. take the rod off the wastegate flap and make sure the rod is just slightly holding the wastegate door tight at no boost? Had bad boost creep i tried all kinds of things but then i just messed with my wastegate for a bit and got it all smooth.

Baisicaly get an adjustable actuator.I think extreme psi has a nice one. Good luck!!
 
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This method helps too...

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If your upgrading the fuel system just tune for the creep and ride it out. I'd frequently creep to 36 plus lbs in the 16g days.

If your really concerned about it you need a larger flapper and stiffer actuator or and external gate.
 
You can port that wastegate hole tremendously. See this post http://www.dsmtuners.com/forums/151781606-post20.html

Thank you... This is exactly what I needed. I hadn't seen this one yet... sure wish I did while the thing was off LOL but heres my next step, cause mine looks exactly like before it was ported

Check out this thread: http://www.dsmtuners.com/forums/art...oler/186525-how-cure-boost-creep-porting.html Note the way this guy "unshrouded" the wastegate passage so that the exhaust doesnt have to make such a drastic 90 degree sweep to get through the wastgate- this is what helps the most, and works for most people to cure the creep. Do you have a pic of your turbine housing after you ported it?

I didnt take too many pics... but heres one
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and heres my O2
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Has anyone found the ported stROFLock O2 to be a cause of creep also? Like to know since Im gonna have it off soon

im running a 14b w/ j pipe and all hard piping to stk smic 2.5" o2 housing with 8" wastegate dump and free flowing 2.5" turbo back exhaust (and egr delete) on a 2ga 7 bolt. installed a new hbc and i have it set to "off" (if there is such a setting) and i boost 12 psi most of the time unless im wot and around 5k rpms then it spikes to 20 psi and i fuel cut. im going to try setting the boost cont higher but i have a feeling im still going to spike at 20 psi..... i think my only choice is an external wastgate and a new exhaust manifold. also i assume the size of the wg flapper is oem for a 14b....any advice would help me too;)

Have you checked that your WG flapper is opening properly and fully? If you have a 2.5" exhaust you shouldnt be having creep issues. Also try bypassing your boost controller (youre not using it right now anyways) and running your vacuum lines directly from boost source to WGA. Youve got a couple variables you need to get outta the way before you can say "my only choice is an external wastegate"

Well that did it!
Before
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After
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Holds 14 lbs solid. Thanks guys. Yet another boost creep victim saved :rocks::hellyeah:
 
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Im getting some creep on my T28. Creeps to around 19-20 psi. I really dont understand why. The car is on a stock o2 housing with 2.5'' Dp to a 3'' exhaust. No cat. I read that they are not known to creep which is why i decided on this option. Would putting a high flow 02 housing and cat help? When i was on stock Dp it sat pretty steady at 16 psi.

S/n. I know how to fix Bc on a 16g would the same apply with the T28?
 
I had to put a in line nipple fitting on my BC line and drill a .008" bleeder hole to get rid of boost creep on my car when I first installed the new turbo... Killed the boost creep problem totally... Start with a .005" bleeder and work larger from there... If you hit .012" - .015 without resolution your problen is likely elsewhere
 
Any turbo bigger than a t25 will creep with a free flowing exhaust in most cases. My 14b doesn't and I have 3in down pipe and exhaust holds 15psi like a champ. The cat may possible help though.
 
I have done a bit of research and I belive my boost creep is caused by my waste gate accuator hose. I have a 16g with an internal waste gate. What I did was put a nipple on my j pipe and ran a hose from there to the accuator. The problem is the nipple in the j pipe is bigger then the nipple on the accuator. I had to start with a big hose then reduce to a small one and I belive that's where I'm leaving from. Basically what my question is how have you guys made ## accuator lines. Better yet is there a better place to hook it then the j pipe. I just want to get rid of the boost creep!
 
when a turbo is internally gated the flapper can some times no open all the way and the actuator needs to be messed with. hook up a compressor set to about 20 psi and if it doesn't open all the way and or quickly then you may have to mess with your flapper.
 
Thanks for the advice. I'm shure that's not it sadly, that was the first thing I did when my turbo arrived before I installed it. Honestly the main reason I think it's that is because before I flaired my line it used to blow off all the time! Now that it dosent I think it just leaks boost.
 
Sounds like it's boost creep. Either Port out the wastegate hole, get supporting mods and tune for a higher psi, or go external wastegate and remove flapper. You could also try a external dump o2 housing as it dumps wastegate exhaust to atmosphere.

I would start out with porting wastegate.

Here my problem not so much boost creep but I have an external O2 housing dump and it'll build 10lbs then around 5k it'll go down to 4lbs and all the time it's like the flapper is open all the time like open manifold loud almost it's crazy( checked timing and exhaust cam is out bout tooth or so)
 
I'm having some bad boost creep, so bad that im maxing out my 190 pump.
-Big16g turbo, ported o2 housing
-3" downpipe and exhaust, no cat
-Evo8 injectors
-190 pump
-2g maf
-punishment fmic
-emissions deleted
-head studs

Spikes to 25 psi and keeps creeping to 29.
So far I have tried the taboo speed shop vacuum line route,
then switched it back from the jpipe for the boost source.
Tried two different hallman mbc.
Also boost leak tested it, replaced seals in tb.
The wastegate never opened when I boost leaked tested it so I swapped the one from the gvr4, now during a boost leak test it does open around 13 psi and fully open at 17-18psi.

Boost still flys to 25 lbs.... I then ran a line from the wastegate directly to jpipe. Boost goes to 15 lbs then spikes to 25 ....pop pop starts to break up and knock

Any input on how I can resolve this issue? Its really getting old. I'd like to be able to run 18 lbs-20lbs without it spiking and hold it right to 7k rpm without it breaking up.

I could throw a 255 pump in and tune around it, but again I don't want to run that much boost.
Also tuning with ecmlink v3
 
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