15 psi stock? Damnit.

[Jeremoose]

Hey all, finally got around to installing my boost/AF gauges and my MBC. Needless to say I was a little disappointed when I was boosting at 15psi instead of the 11-12 psi I was expecting stock. So much for upping my boost for now I guess Any of you had any experience with 15psi stockers?

 

[Ultimatedsm]

Did you do the BCS mod where you remove a little piece from it? If you did, well thats what the does.

 

[larsenracing]

What size exhaust do you have if its 3" that may be giving you a little more psi also did you have your MBC in before you put your gauge in. I have never seen a stock car run 15psi. Also check to see if the restrictor is removed from you boost controller solenoid if you were at 15psi before you installed the mbc.

 

[Jeremoose]

I didn't do the BCS mod, but I'll check to see if the previous owner did it... I installed my MBC and boost gauge all at the same time btw.. This is weird

P.S. All that's done with my exhaust is the cat is stripped and I have a performance muffler.

 

[daren_p]

Factory cat is a good sized restriction, so that would account for some of you extra boost. Check the bcs & also are you still running the stock bov? (update profile if not). The stock 2g leaks around 12 psi so you will be making the turbo work harder to try and sustain the higher boost level. This will greatly shorten the life of the tiny t25 & also produce a hotter intake charge which kills power.

 

[19Eclipse90]

Did you adjust your MBC after you put it on? If yes, nevermind... if not, continue reading....
Is it not possible that 15psi is just where the MBC happened to be set when you installed it? When you put the MBC on, that is then what controls the boost, and it was set at 15psi instead of a stock 11-12. No DSM runs 15lbs stock that is for sure.

 

[daren_p]

Did you adjust your MBC after you put it on? If yes, nevermind... if not, continue reading....
Is it not possible that 15psi is just where the MBC happened to be set when you installed it? When you put the MBC on, that is then what controls the boost, and it was set at 15psi instead of a stock 11-12. No DSM runs 15lbs stock that is for sure.

That is a very good point that we didn't even think about. Even when turned all the way down, mbc's will still put a "restriction" in the actuator line, increasing the boost slightly.

 

[Jeremoose]

Heheh, thanks a lot guys, so many good suggestions I'm still at work though so I'll check on this stuff and let you know what I found out as soon as possible..

I'm beginning to suspect I just didn't adjust the MBC though (I don't remember putting it at its '0' setting), I can be pretty forgetful.

 

[Gamble97]

Ah don't feel bad, my stock t25 is boosting at 20psi.

 

[Jeremoose]

Ah don't feel bad, my stock t25 is boosting at 20psi.

That sucks man But oddly enough it makes me feel a tad better, .

 

[Gamble97]

That sucks man But oddly enough it makes me feel a tad better, .

it bothered me at first because I always thought that the more boost you run the more power you make. It's not a big deal really, some people are making just as much power as others on the same boost lever or even lower.

 

[Jeremoose]

Okay so apparently the boost controller doesn't seem to be doing anything at all... And the BCS doesn't appear to have been done.. So is it possible for the reduced back-pressure from the removal of the stock cat increasing the psi (like stated above)?

 

[daren_p]

Okay so apparently the boost controller doesn't seem to be doing anything at all... And the BCS doesn't appear to have been done.. So is it possible for the reduced back-pressure from the removal of the stock cat increasing the psi (like stated above)?

How did you hook the boost controller up? Are you still running the bcs, if so you haven't hooked up the mbc correctly. How did you test the boost controller? Like I said even with it turned all the way down, it still adds a restriction in the system and will raise your boost. Yes removing the cat, or any part of the exhaust restrictions will increase boost.

 

[T is for TURBO]

mine was spiking at 16 and held at 15, still had the BCS restricter. I ran it like that for about 10K miles I had the car (now has 66K) before swapping in my BT-28... BTW, my T-25 had ZERO shaft play...

 

[Jeremoose]

To be honest I don't remember how exactly it was installed, a friend was doing it while I put in my gauges, . I'll have to check first thing in the morning, its dark out In any case I came to the conclusion it wasn't working properly when I tightened it about 1 full turn with no added boost, then loosened it back to where it was with no change in pressure either way. I'll check all the hookups first thing in the morning and get back.