i could use some help. problem with boosting.

[forksquared]

ok fist off i searched and read like 8 threads but they didnt really answer anything for me. i have a t28 turbo with custom 3" turbo back exhasut. the greddy turbo extension. greddy fmic. all that. here is my problem. my car will boost to 5psi real quick like at 3~~~rpm. and wont get to 7 untill like 4500-5000 i dont understand why. it like boosts in 2 stages its weird and annoying. and when i put in my manual boost controller and turn it up it doesnt do a damn thing. can someoen please help me out here? im geting upset. i know its aobut to snow but i would like to get this fixied befroe it does so i can take it on a drive with higher boost before the snowfall.

[Drift_S13s]

try an Apex'i AVC-R

[forksquared]

i have no job at the monet cant afford. and i have my manual boost controller not connected right now just stock to the wastgate and it only boosts 5psi untill like 5000rpm

[SRPWR]

have you checked for boost leaks? Even the smallest leak needs to be addressed. Also check condition of your turbo. shaft play.ect.

[forksquared]

i know the turbo is good i bought it brand new about 3 months ago. i will tomorrow check for leaks. somehow...

[SRPWR]

Not to say that this is your problem but a buddy of mine had the same exact symtoms as yours. We checked every thing besides the turbo because it was brand new. He has a GT2871r. He only put about 25 miles on it and then all of a sudden it wouldnt build anything above 10psi. No smoke, no grinding sounds or anything to suggest the turbo. Any ways I ended up pulling his turbo off and apart and found all of the exaust blades bent and sheared off. Luckly it was covered under warranty. My point is, if it is your turbo, depending what kind of warranty you got, it might be worth looking into. Let me know what you find out, I might have some more ideas. Also check the ball and spring in your MBC.

[forksquared]

yea i will pressure check my piping and look at the turbo. also i took my controller off then i was playin with it and unscrewed it to far and it came apart and i dont remeber how the ball/spring went in it haha its a perrin one. i got my trubo from 240sx motoring. i dk if it is under warenty or wtver it better not be the turbo i would be pissed!

[SRPWR]

To be honest with you I would be pissed too if it were mine. First I'd check for any leaks at all, boost and vaccume. BTW, at idle, whats your vaccume sitting at? 2nd Im assuming you are running a internal wastgate. Maybe that went south. Ive seen that to, not to often, but if its not working properly it wont allow you to build boost either. Id check these two easy things first. LMK.

[forksquared]

at idle the vac is a little above 20hg~ oh and by any chance do you know the right way to put the perrin boost controller back together? haha

[SRPWR]

I see a problem there. Every SR that Ive ever worked on and seen is sitting at about 16 mine included so that would suggest a vacume leak somewhere. Throughly inspect all your vacume lines. still check for boost leaks because that can throw it off as well. And sorry Im not sure about your BC.

[forksquared]

i dont have my car today ghey. i wasnt thinking this morning and let my friend take it to work cuz his car is broke down with some repairs. it was early and i didnt htink aobut it now im kicking myslef. anyway could this be a problem? i read that the wastegate can get its signla from the hot pipe but my hotpipe didnt have a hose nipple. so i had a frend of mine put one on it for me. it is before the bov on the hotpipe. could this be causing it to open early or soemthing? also. the little vaccuum line under the throttle bodt like real small one. i just have that blokced off should i tee it in with like the one to the bov or soewmthing?
Modified by forksquared at 11:21 AM 11/3/2006

[SRPWR]

There should be nothing teed into your hot pipe. On mine it goes as follows

From waste gate to BC.

From BC to the nipple above the throttle body on the right side (u facing th motor)Yes keep the nipple below the throttle body blocked. there is a small nipple on the intake pipe. where do u have that going?Since u dont have a BC, jut go directly to the right nipple.

[forksquared]

the nipple on the hotpipe goes to the wastegate. the bottom one is blocked then the otherones on my throtttle body go to my fpr/bov/and boost gauge. i read that old hotpipes used to have a nipple on them for thre wastegate. but they stopped putting them on cuz they broke during shipping so i made one myself was that a wrong move?

[SRPWR]

Yes. On my car I have nothing on my hot pipe what so ever. Mine goes straight from my turbo to the FMIC. Do you have any pics of yur engine bay so that I can see your vacume line routings. I would take pics of mine but someone stole my digital camera. Oh also, I ffoget what its called exactly, but do you have that little thing installed tha has 2 little nipples coming off of it. If you got a front clip it would have come with one. it also has a wire harness onit. Might be located close to your ignighter.

[forksquared]

um i can try to get pics but my camera is broken i may be able to barrow one. and i have no clue what you are talking about for the thi8ng near the harness

edit: this isnt mine only samething just different boost controller so it must work right someoen else is using it

[SRPWR]

I really cant see anything there. That little thing that I was talking about, i heard some one today call it a boost sylinoid. I dont think every one runs one so I dont think that it is absolutly nessasary. I run mine but a buddy of mine does not. I really think that your problem will be in your vacume line set up. question is... have you had this problem since day one? Have you checked for leaks yet? I am going to try and get some pics of my vacume routings. (everyone is being a d**k about letting me borrow thier camera) and I cnt drive to thier place because my water pump went out. I'll do my best.

[forksquared]

yea it seems like it is working now. i dk i didnt do anyhting but put my boost controller back in and it is boosting like 15psi. so i had to stop and turn it down i dk what it was weird. i didnt even chack anything yet cuz i had to go to help my friend. but it seems better now weird huh? thanx for all your help