Stock Downpipe Size?

[prophecy7115]

Ok i was checking out my exaust today (bored), and i discoverd a gutted cat, and the outlet on my downpipe is 2 1/2 inches? i thought the exaust on car was stock, well besides the cat-back i put on, it was a good surprise. What is the outlet size on the downpipe.

 

[GSTBlack95]

close to like, 2 inches I assume, I am wanting to say like 2 1/4 or something.

 

[steve-o_95_GST]

2 1/4 is right

 

[prophecy7115]

Why iam i still slow?. I have a 2 and a half inch downpipe, 2 3/4 catback and i am still slow?

 

[steve-o_95_GST]

is the exhaust and the intake filter all the mods you have? ( besides drivetrain) if so that isnt going to get you much. you still have all the stock piping and turbo. the t-25 is a horrible turbo as it cant put out much boost efficiently let alone hold it. you also have stock fuel, with those mods you cant expect to be much faster than a stock turbo dsm.

to get the most out of what you have you could do a boost leak test and find any leaks, get a mbc ONLY after you have gotten an aftermarket boost gauge. also they have the free mods listed in the tech section.

-steve

 

[prophecy7115]

Yea i have a boost controller, and i hks ssq. on stock piping i bought that 6" long tube with the flange in it. i set it at 14psi and it feels the same as 12psi and at 15 the same as 12psi? i guess i expect to much from my t-2smal

 

[GSTBlack95]

Thats odd you feel the same power at higher psi as 12. I went from 11 to 16 and I felt a HUGE differnce in power when I upped the boost.

 

[prophecy7115]

Well i have this wierd problem, i cant run my car recirculating, if i do i run extremely rich and slow, so i have to have th BOV dump tube, gapped from the bov about 1 inch, so its recirc and sucking unmetered air, If i have it completly closed like its soppose to i run like crap, and no i am not trying to hear my bov, i have a ssq so either way it doesnt matter. Why does my car do this, i have spoken to all my friends that can visually see it and they all shrug there shoulders and tell me they have no idea and have never had to deal with somthing like that.?? i am all stock? well with a blow of valve. i also have all stock piping.? i think my ecu is messedup and i recently changed my maf.

 

[marq95gst]

Follow the upgrade path. Make sure you have a boost controller, all free mods, boost gauge, 3" downpipe, and at least 190lph fuel pump. At 15-16psi you WILL feel it. And thats on 91 octane. After that you'd be ready for a bigger turbo/fmic....

 

[BOBS90TURBO]

I had the same problem a couple of years ago and it ended up being a bad ecu.