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

[DSM4me44]

*Try rewiring your fuel pump.
*Lower your boost.
*Port, port, port (manifold, o2 housing, etc)

Otherwise....

1. Get a set of bigger injectors

2. Get a new fuel pump (190 or 255 w/ AFPR like DSMj89 said)

3. Get an something to tune with (SAFC/SAFC2, DSMlink, etc)


Can you actually see the boost creep or do you think you have it because you hit fuel cut?

 

[ricekilla77]

how do i port the waste gate exactly? and right nwo there is a evo fuel pump in the car and i want to put in 650 cc along with the safc 2 but it will take me a little time to get those. so by just porting the waste gate will that eliminate boost creep? and once the boost creep is eliminated wont my fuel cut problem be solved to because the mbc is set to 14 psi?

 

[ricekilla77]

ya there is a auto meter boost gauge and it goes up to 14 pretty quick and then slowly climbs to 15 then 16 and hit fuel cut. the fuel pump has been re-wired but nothing has been ported. so before i get the required fuel system upgrades can i get rid of the boost creep causing my fuel cut? i was also told by putting in a 3 in GM MAF and having it tuned at 14 psi by ams this could get rid of the fuel cut problem is this true?

 

[Dsmj89]

As long as you keep the car at no more than 12 psi to be safe there will be no problems.
You really don't need a gm maf/maft conversion unless you plan on doing 500+hp.

 

[DSM4me44]

Porting your wastegate IMO is a bad idea. I tryed it on a 14b housing i had and what happens is when you port it is easy to "unlevel" the surface. Then your flapper won't seal completely and you will not only not have boost creep, you won't be able to build boost quick at all. Port the o2 housing first.

 

[ricekilla77]

So by porting tho o2 housing will that lessin the boost creep and is there anything else I should do?

 

[->PrOjEcTGS<-]

The cheapest option is to put a silencer in your exhaust. It will restrict your exhaust gas so that it keeps your boost lower. That should keep the creep to a minimum.

Or just buy the mods needed to run big boost numbers.

Your choice...

 

[zdravko_k2002]

Hello I seem to be having a very frustrating problem with my car. It's got a MHI Big 16G and I was having boost creep problems. So I decided to go with an external wastegate. Got a Tial 38mm with a Hafe Exhaust manifold to bolt up to. Its got the .6 bar spring which is 8.7 pounds of boost. I welded the flapper shut all the way around, but did not weld the little hole where the intsernal arm bolt up to...that is still left the way it is...open with nothing there. So after installing it I am still getting boost creeps even though it is set at 8 pounds. I ran it with my mbc Hallman and directly from the wastegate and both times I get same results. My car is creeping up to 16-18 and hitting boost cut. What could be causing this problem. Do I need to weld the little hole up as well where the internal WG arm bolts up to, or is there something else Im missing. So far Ive checked all mo hoses and they look fine. Any help would be appreciated as I have been dealing with this problem for almost a year and thought going external would fix it but it did not.

 

[jrohner]

I don't know, but I bet that for the money you spent on the gate & manifold, you could've got the supporting mods to run the boost it was creeping to.

 

[Boosted6]

it seems that you should try running the wastegate w/o a boost controller.maybe yours is defective?i battled boost creep on my internally gatyed 20G for a few weeks then i went and bought an Apexi AVCR,that took care of it.

 

[zdravko_k2002]

It is a Hallman boost controller so I dont think its deffective but I did take it out and ran it directly to the wastegate and still does the same.

As for the supporting fuel mods, I just want to run 14 pounds max on my car so I want to keep my boost down but it keeps creeping up and I dunno ### to do next. I am trying to take it to a DSM shop around me but it seems that DSMotorsport have closed down and I dunno if Broadway Performance can help me out or Turbo Trix or anyone around here. Im willing to dump another200-300 just to fix it but who knows what it is.

 

[Boosted6]

Try running a vacuum line directly to the wastegate,no tees of any kind.is your external wastegate atmosphere dump?Are you sure the wastegate has the proper washer between the bolt and nipple?Turbo trix will be your best bet,they are HIGHLY experienced in the DSM field.Make sure no check valves are being used.Have any detailed pics?

 

[zdravko_k2002]

Boosted6: I did run it directly to the WG without any t connectors and still does the same thing, as a matter of fact thats how its running right now without the boost controller just directly connected. My WG is atmosphericly dumping. What kind of washers do I need between my bolt and nipple. It is a tial 38mm so they sent me the nipple that just screws in the whole and the vacuum line just plugs right in the nipple, I am not sure about this washer you are refering to sorry but I am not too experienced with this as my brother actually installed it for me but he is pretty knowledgable. And what are the check valves that should not be used as I am not familiar with them as well? I do not have any pictures yet I will try to take some and see if I can figure out how to upload them here. Sorry in advance for being a newbie and not knowing some of these things you are refering to and thanks in advance for the help and thanks to all who have responded so far.

 

[Damills]

Which hole did you screw the nipple into on the external wasegate? The side of the wastegate is used for vaccum source and the top is used for a boost controller. Make sure your vac source is going into the side not the top. Just my 2 cents

 

[banshee04]

well you need a new spring if your running 18 psi and u have an 8 lb spring, then its not enough.

 

[DSMsOwnYourV8]

pics would help so we can see if it is installed correctly. Also, I'm pretty sure you have to weld the internal wastegate shut. Btw an external wastegate is a great mod because if you upgrade turbo's again, you'll already be one step ahead of the game.

 

[DSMsOwnYourV8]

well you need a new spring if your running 18 psi and u have an 8 lb spring, then its not enough.

That's because everything probably isn't hooked up right. If you are just running off the wastegate, the spring should open up at 8 psi if you have an 8psi spring.

 

[zdravko_k2002]

First yes the vacuum line is hooked up to the side nipple and the top one is just sitting there with nothing running to it since I do not have an electronic boost controller. As for the hook up I took the car to a friend of mine who is very knowledgable with turbo cars and he inspected it thouroughly and he said everything looks good and connected in the right places no vacuum leaks and he gave me the advice to see if I have the wrong spring in the WG and a couple people have been telling me that now so even though I bought it from extremepsi maybe they did put the wrong spring in there so I dont know when I will have time to take it apart and check it out, since I am approaching the end of a college semester and am pretty busy with school, but I will keep you guys updated and again thanks for all of your help.

 

[VETTE_50_TH]

This is what you need to do. Remove the MBC and see what the car goes to. If it goes over 8 psi, then the wastegate isn't properly working, or has the wrong spring. However, if it does, then you hooked up the mbc incorrectly. You do have it correct with it being off the side of the Tial, but i think you have the connection on the MBC backwards. This is typical.

James

 

[DSMsOwnYourV8]

This is what you need to do. Remove the MBC and see what the car goes to. If it goes over 8 psi, then the wastegate isn't properly working, or has the wrong spring. However, if it does, then you hooked up the mbc incorrectly. You do have it correct with it being off the side of the Tial, but i think you have the connection on the MBC backwards. This is typical.

James

Bingo

 

[zdravko_k2002]

I did remove the MBC, I think I stated that a couple of times above when saying it is direclty hooked up to the wastegate. As of right now i do not have the MBC hooked up it is running directly and creeping bad not staying at 8 pounds, so the WG must have the wrong spring in there or messed up somehow. I will try to check into this very soon and see what is going on.

 

[DSMsOwnYourV8]

Yeah if everything is hooked up right then it is definitely the wrong spring or the wastegate isn't working properly.

 

[zdravko_k2002]

I am actually going to borrow my friends tial 38mm WG tonight and hook it up tomorrow to see what the outcome is going to be and keep you guys posted. If the creep is gone then I will open up my WG to see which spring is in it and go from there. His spring is somewhere around 10 pounds so Im going to hook it up directly to the WG without the MBC and see if its going to hold the 10 pounds. I will let you know how it worked out tomorrow.

 

[kylush]

Ok I recently installed my defi boost and egt gauges along with my aem wideband and noticed that I'm getting boost creep/spike all the way up to 18 psi at times.. At this point it looks like it starts to go lean and then fuel cuts. My mods are all "free" mods.. (bcs restrictor removed, hacked MAF, hacked aircan, all emissions stuff removed) and then a 3 inch turboback exhaust.

I've heard of porting the O2 housing and turbine housing to help with boost creep but I am planning on upgrading my turbo and don't really wanna put work into this little 14b. My goal for this car now is about 350whp. I just want a turbo that will support that and not boost creep. I don't know if that means it will have to be externally, or internally gated or what not, recirced or open dump I'm open to any suggestions.

 

[1gDSM4g63]

Porting the o2 housing will help decrease boost creep, but a recirculated or open vented o2 housing would help more, but you will not get 350hp on a stock turbo. Go to the TECH section for upgrade sequence and check out what people have made on Dyno Runs in the MEMBERS section.