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

[ryan11]

Here is my problem, I recently purchased the b16g and ported it out to fix or help the common boost creep problem associated with the 16g's. After I did the port and got the turbo in the car I took it out for a drive. I had the boost set at 10 with a pull from 2nd gear. The boost held untill 5k rpm and then crept up to 17 and held untill redline. I thought ok it can hold boost decently so I can turn it up from 10 to 15, When i did this the boost crept all the way up to 22 by 6k rpm. Is it common for boost creep to work like this? Will it creep worse the higher you turn it up? If it holds 17 when it is set at 10 why cant it hold 17 when i turn it up? My thoughts make me think that it may be the boost controller, Any help on this or anybody who has also experienced this with some advice would be great to hear. Thanks.

Ryan

 

[Froyd79]

Did you check to make sure the actuator is not loose? Internal or external gete?

 

[disciplekyst]

Hi guys, I recently got a 2.5" turbo back exhaust (w/o O2 housing) because I heard that a stock turbo/wastegate wouldn't get boost creep with that diameter.

The problem with my boost is the following: It CAN be set to 16 psi below 4K, but after it begins to increase gradually to a dangerous 19 psi at about 6k (I don't have any fuel mods). All this after the exhaust install (which is VERY unrestrictive by the way).

Besides porting my wastegate outlet (which is time and/or money consuming), is there something else that can be done to fix that?

Thanks for you help

 

[SOADweskey]

Well it is true that increasing the size of the Wastegate passage in the O2 housing will help fight boost creep the other things will make it worse. A very free flowing exhaust makes boost creep worse if you are still running an internal wastegate.

You have several solutions....
1. Get an O2 housing that has an external dump tube.
2. Properly port out the wastegate passage in the turbo and the O2 housing.
3. Get an external wastegate on the exhaust amnifold.
4. Get all the proper supporting mods and just run at 20 psi (My favorite solution)

This thread has some great information on how well the actuator actually works and what can be done to make it better.
http://www.dsmtuners.com/forums/showthread.php?t=267309&page=1

 

[SethA]

The porting labor really isn't that bad if you do it yourself and you can come up with a die grinder. The only cheaper and easier (and less desirable solution) is to add restriction to your exhaust (run a cat?). Another way to go is get some logging tools and see if the boost creep is really a problem. The funnest solution as stated above is get all the stuff you need and just run more boost (I know, cheaper said than done).

Seth

 

[disciplekyst]

Thanks for the input guys. I'll probably go for the porting job.

But in case I get the money, what would be the CHEAPEST supporting mods to run 20 psi quite SAFELY? Remember that i don't have any fuel mod at the moment.

a 190 lph fuel pump would probably do for fuel supply, as for fuel control i'm scared about the complexity of S-AFC tuning AND price, is there better solutions for me?

Thanks again

 

[SOADweskey]

I don't know what the bare minimum requirements would be. My car has a 190, 720 injectors , and I am using DSMlink for tuning.

It also depends on the gas you have. Around here the best I can get is 91 from the pump so the 720's are a great help but they are to big to be accurately controlled by an AFC.

 

[disciplekyst]

Worried about sound on that one...

 

[SOADweskey]

got open dump?

If that question was to me, the answer is no. I have a Big 16G and an EVO3 O2 housing and I didn't port the wastegate passage in the 16G but I did completely port match the O2 housing to the exhaust side of the turbo.

 

[ryan11]

Internal gate and yeah I hooked it up to a air pressure source and it opened fine.

 

[SethA]

If you shop around and are willing to buy used stuff you can get by fairly cheap. If your plans call for a bigger turbo/more boost, keep that in mind so you don't have to buy stuff twice.

to start you need:

1) some sort of logger (used palm pilot w/ cable and free software?)

2) fuel injectors (used evos?)

3) fuel controller (afc or translator used?)

4) fuel pump (190, might as well rewire while you are at it)

Every car is different. Like I said before, start with the logger. If you know someone who has a wideband you can borrow do that too, it can tell you a lot about your fuel needs.

Seth

 

[disciplekyst]

Thanks for this information SethA,
I have one problem with loggers though, it's that i just can't find some sort of tuning guide to help me get started with tuning, ----i'm sure i'm really not alone in this situation---

Seems like you have to learn the basics of fuel supply and injector size and then start playing with the tuning tools, Feels like Trial ane Error to me, which scares me

I read the DSMlink user guide yesterday, and i understand the basics, but i just wouldn't know where to start if i ever get one.

If someone has a link on a good tuning guide or has some useful tips with what to begin with, please help us beginners

Thanks again

 

[EagleTalonTim]

I just did a 7bolt to 6bolt JDM swap with a cyclone intake and took it out on the interstate for a test drive. When I put my foot into it, the boost went up to 20psi and dropped back down to 12 psi where I have the boost controller set at. I don't even know if I have the cyclone hooked up right. Are the flaps in the cyclone normally open with the engine off, or normally closed?

 

[oldman420]

Stock 14b?

 

[EagleTalonTim]

no, stock 13b....automatic

 

[oldman420]

Re-check to make sure your mbc is hooked on right. I'm not completely sure about the cyclone, but it almost sounds to me like you mbc is hooked up backwards. I don't want to seem insulting i just always check the obviouse first so it's not overlooked.

 

[Phantom DSM]

Hopefully the mbc is hooked right: the bottom nipple goes to the wastegate and the side nipple goes to the nipple on your j-pipe coming out of the compressor housing.
Your boost creeping problem sounds like your wastegate is not holding even if the mbc is set too low. It is also common for the turbine side for those turbos to start cracking, which in turn causes exhaust leaks.
If you have a 3" downpipe on a stock o2 housing like i do, you will notice massive boost creep no matter how low the mbc is set. Get rid of your 1g o2 housing and get a 2g and port it.
I hope this helps, and correct me if im wrong guys. Im suggesting what i had in experience with weird crap like this.
good luck

 

[EagleTalonTim]

I will check into that after I figure out what my problem is with my tranny. Got to love these cars. Was trying something and about to go for a test drive and bam! Car will not drive anywhere. I hate auto's! Wish I had the money for a swap!

 

[Phantom DSM]

how is the transmission acting ?

 

[EagleTalonTim]

http://www.dsmtuners.com/forums/showthread.php?p=151288272#post151288272

 

[EagleTalonTim]

ok, go the transmission fixed...all i needed to do was reset the TCU . Now......I am still hitting 20psi on take off, then it drops right back down to 12psi where I have the boost controller set at. The boost controller is hooked up correctly and I even checked to make sure the ball inside is not stuck. I took it out for a drive today and laid into the throttle and out of the blue it started popping and sputtering. I read up on the fuel cut threads and they say it is more than likely my plugs and wires. Just yesterday, I took it for a drive and it was perfectly fine. I did not touch anything. Would the plugs or wires just go out like that? I have not run a boost leak test yet due to work What should I check on about the sudden 20psi boosting? If it is the waste gate, can I pull the one off my old 7 bolt and put it on the JDM motor? They both have the same turbo.

 

[Menacing talon]

I dont think its fuel cut,If it was fuel cut you would know it. Youd be checking in your rear view mirror to see if your trans is behind you or looking to see if you just tanked a large animal. Sputtering might be the plugs and/or wires. might be a clogged fuel filter as well

 

[DontStartModdin]

I just finished writing up a well thought out and researched thread about the possibilities of my car getting boost creep. Instead of writing it all over again I am just going to get to my main question. What is a rough estimate of the percentage of 1g that install full 3 inch exhausts on there cars to get boost creep? I have a manual 1990 Plymouth Laser FWD turbo. Mods as follows;

*Air intake
*Hard upper intercooler piping
*2g ported exhaust manifold
*SBR manual boost controller (set at 14psi)

I am planning on ordering a full 3inch exhaust from dejontool. Including an evo3 o2 housing. I was concerned if I should port the wastegate exhaust hole right away to help avoid boost creep? Or just bolt on the exhaust and hope I dont get it? Also what parts should be replaced when doing this? (crushwashers, turbo/wastegate gasket, oil feed, etc) Any input is highly appreciated. Thanks. BTW I am a noob to DSM's, but I am fairly mechanically inclined when it comes to working on cars. (recently converted from hondas)

 

[just2asian]

What turbo on you running? Now you have to keep in mind that each car reacts differently. I had a buddy with the same turbo setup as I did and he would boost creep, but I didn't. It all depends the car.

 

[99gst_racer]

If you're running an un-ported 14b with a 3" turbo-back, then you will probably creep. I would definitely recommend porting the turbine housing to avoid creep, and to insure proper boost control.