turing boost down

[chehsgsx]

i just got a manual boost controller (gillis 0-21 psi spring). its hooked up to the turbo j pipe like the forums say to do, but my boost wont seem to stay down below 15 pounds. im not sure why this is happening?

so i hooked up the j pipe strait to the wastegate with no mbc. and now the boost sits at 14. im just wondering why with no controller im ok and with it i boost to high??

i was under the impression that with the j pipe hooked rite up to the watsegate id have zero pounds of boost.

also my friend has a gillis that has the 16 to 30 pound spring. i did a comparison to make sure they didn't send the wrong one, and mine is alot weaker like it should be.

just trying to clear this up, thanks for the help

 

[solidviper89]

If I recall correctly, hooking up the jpipe straight to wastegate, will allow you to boost the lowest that wastegate supports (i.e. that waste gate is set to 14lbs and so you can not go lower than that; unless of course you have exhaust leaks, or boost leaks).

 

[chehsgsx]

hmm that does make sense now that i think of it.. well is it ok to run like this?

i don't want anything higher then 14 because of fuel cut. just playing it safe at the moment, just until in invest in the fuel system some more

 

[habitatguy187]

If I recall correctly, hooking up the jpipe straight to wastegate, will allow you to boost the lowest that wastegate supports (i.e. that waste gate is set to 14lbs and so you can not go lower than that; unless of course you have exhaust leaks, or boost leaks).

I ran straight off my j-pipe to wastegate and would only hit 9psi. I don't think wastegate pressure is that high. In a 1g it's 11psi stock.

 

[chehsgsx]

hmm well if its 11 then there's something wrong.. that would be the wastegate rite? i took it out and pressure tested it and it didn't leak at all. hmmm where should i go from here?

 

[spydermanX98X]

It'd be nice to know you're turbo setup. If say you have a 16g and your boost won't stay down it may be classic boost creep.

 

[habitatguy187]

It'd be nice to know you're turbo setup. If say you have a 16g and your boost won't stay down it may be classic boost creep.

Right, your profile shows you have a 3in downpipe and catback. What's up with your wastegate? Are you still using the stock o2 housing?

 

[chehsgsx]

stock turbo, stock o2 housing, stock wastegate

sorry about that, hope this helps

 

[gofer]

the wastegate actuator on the t25 (the turbo that comes stock on the 2g's) should hold boost anywhere from 9-12lbs depending on your car. since you've got a bigger exhaust your turbo will boost more since theres less restriction which makes sense that your holding 14psi with no boost controller. my question is why did you buy a boost controller if you want to run 14psi in the first place? your wastegate is controlling the boost at the level you want it so until you get some injectors, a fuel pump, and an safc or dsmlink and have the fuel mods to support running more that 14psi keep the boost controller in the closet.

 

[chehsgsx]

i got the mbc because my boost was always changing ( max and min at wot)
so i figured the mbc would help but nope .. its no longer holding 14 pounds anymore its up to 15 /16 again (even with no mbc)

if i get near 15 i have fuel cut, so is there anyway to get it to go down to 12-14 range? i was thinking of getting a different wastegate with a softer spring and moding it to work on the turbo. nah or yea??

thanks again for the help

( as a side note today i used my compressor and put about 20 pounds in the waste gate and it dosnt seem to be oping all the way, I left it in the car and it just dosnt seem like the gate is opening a lot. idk if its supposed to open all the way or not but figured id let everyone know)

 

[chehsgsx]

i found these
Internal Wastegate Actuator - Special 7 psi: atpturbo.com

Internal Wastegate Bracket: atpturbo.com

i believe it would work. says for garrett t25 turbos. the wastegate is a low 7 psi one too

let me know what you guys think

 

[gofer]

take this in stride because it could be a lot of work or something real simple thats causing you to boost 16-17psi when your trying to keep it at 15.

hopefully you have to have someone in the area that either has a t25 sitting in their garage after a turbo swap OR has a t25 on their car that you can pull a wastegate actuator (wga) off of and test it on your ride. its about a 30 minute removal/install and simple to do, im saying its not your wga though.

you can also spend $15.00 at radioshack and go to VFAQ Site - Visual Frequently Answered Questions and go to the "fuel" section and do the fuel pump rewire for a 2g. really easy just print that puppy out and follow her step by step, that stopped me from hitting fuel cut at 16psi (but that would be you dealing with the issue since you'll still be running 16psi after this mod).

now if you absolutely want to run 15psi and it wasn't your wga take off your 3" dp and put on the stocker. that is whats making your little t25 want to spool up to 16-17psi because the less restriction in the exhaust.

the quickest and easiest way to fix your problem is take off your 3" downpipe and put the stock one back on... it will probably bring your boost down to 12-13psi, then you can put on that mbc and get her back up to 15psi.

don't waste your money on a lower psi rated wga, spend it on injectors and walbro 190 fuel pump so you can safely run 16psi.

 

[chehsgsx]

y is it that a dp could cause excesive boost.. this dosnt make sence to me.

so long as your wastegate is working properly y would it care about the back pressure?
and i realy need to get boost under control so i have to fix the boost issue. (also dont have the stock dp)

iv read alot about the rewire and id rather just leave it alone rite now and fix the boost ( already have a 225 pump just need a fpr)

as far as haveing someone to swap wastegates.. i dont really have alota dsm friends anyone in the area want to help me out??

thanks again for the info
im not shooting anyone down i just want to make sure i can control my boost before anything eles

 

[gofer]

alright... well, seems like your kinda stuck.
ill tell you why i think its your down pipe if your wga is working correctly though... hang on hopefully i don't ramble on and make no sense in doing so.

hows your car spooling up anyway??? when you go WOT does it jump to say 12psi then climb to 16+ or does it just jump straight to 16psi and you hit fuel cut?

your stock downpipe is something like 1.25" diameter (weak) so it only allows a certain amount of exhaust gas to push through it so fast. granted, you are still running the stock t-25 turbo but by opening up the exhaust at/before the cat its allowing the turbo to spool more efficiently which in turn increases your boost. you have a 3" downpipe to cat thats more the TWICE the size of the stocker dp. take a coffee stir straw and blow through the thing as hard as you can (your face turns red and looks similar to this ) thats what your turbo is doing stock. now pick up a paper towel roll and blow through it (your face should look something like this ) and thats what happens when you install that big downpipe.

the way its looking right now i think your best bet is to spend the $15.00 to do the fuel pump re-wire, then once you get the $$$ get an afpr. i guess you could spend the $85.00 on a wga that opens at 7psi or whatever but none of those you posted up were specifically for a t25 turbo. after modifying this baby wga to fit your turbo you could have spent the money on an afpr since youve already got the 255 on hand. see what im saying? i know it sucks to say but your trying to make your car faster anyway right, so why lower the boost and besides its only 16psi. thats right where most run their t25 until upgrading turbo's and your motor can handle it, just get the fuel system up to speed.

your cost to go slower = your cost to go faster

think about it!

 

[chehsgsx]

hmmm i see what your saying, oh the car boost up to about 15psi.. then creeps down to 14 then spikes again to 16 that's why i thought it was the wga. those ones that i have there, that website is from garrets website so i figured that was a good place to start.

im gona try and do the rewire and see if that helps, im just nervous about that wga with the way the boost is always moving around ( if i do the rewire i want to lock it in at 16 but at the moment i cant lock in anything )

 

[habitatguy187]

It basically sounds like you have boost creep. Go to dsmtuners vfaq and look in the turbo section. There's a solution for curing boost creep in there. It's written by some guy named peepers or somethin . If you don't know what boost creep is it's when the exhaust gas can move through the turbo easier than it can move through the wastegate, solutions are, buy a bigger wastegate, port the wastegate, or do the wastegate mod in vfaq. Don't spend your money on another one though. And you don't need to do a fuel pump rewire with a 255.

 

[chehsgsx]

ohh man hacking into the wastegate idk about that ,, that kinda scares me. he says in that post that buying a garrett wga is a good alternative?? so idk why i don't just get the new wga. new wastgate= works outa the box, and reliable mod= i could possibly screw it up and then have to buy the new one



thanks for the info on the 225 pump .. i thought u didn't have too.. all i need to run it is a fpr since i don't want to over run the stock one

 

[habitatguy187]

I forgot to mention the o2 housing. If you get a ported 2g o2 housing then your problem will most likely go away. Or you can buy stainless steel ones off ebay but idk how good they are. Either way with an upgraded exhaust you should have an upgraded o2 housing.

 

[chehsgsx]

any down falls with a 3 inch one? or stock sizes is best???

 

[habitatguy187]

any down falls with a 3 inch one? or stock sizes is best???

not as long as it bolts up to your current setup. Anyone on here ever use an ebay o2 housing?

 

[datrip]

I have used an ebay o2 housing before, but I think it was X02 brand.