ok im bout ready to turbo my built (but not sleeved) dohc zc, im going to use a t3 (.42/.48). A guy thats helping me with my project says to use a smaller diameter charge piping and then use a 2.5 dp. so what do you guys say?? (oh and my exhaust is 2.5 all the way back)

(on my last turbo setup i had a t-25 on my stock zc and all of my piping was 2.5, i noticed a bit of turbo lag)

 

personaly i wouldn't go much bigger then the size of the outlet on your turbo. Exhuast, definetly 2.5, not gonna hurt anything by going bigger.

 

i dont have the turbo with me right now (it's at my school) and im tryin to order my pipes.....do you (or anyone) know the size of the turbo outlet on a t3?

 

you're not gona make a ton of power... 2 to 2.5 inch will work fine.

the bigger the dp and exhaust the better

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDogg &raquo;</TD></TR><TR><TD CLASS="quote">you're not gona make a ton of power... 2 to 2.5 inch will work fine.

the bigger the dp and exhaust the better</TD></TR></TABLE> yeah i know im gonna make less then i thought i would (people say it's a small turbo...but it's bigger then my old t-25) anyone know the size of the t3 outlet?

 

im running 2.25 on my zc

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by second edition &raquo;</TD></TR><TR><TD CLASS="quote">im running 2.25 on my zc</TD></TR></TABLE> anyone know the size of the turbo outlet??

 

I believe it's right around 2".

 

2.5" on t/b side and 2.0" on turbo side

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbocivic94 &raquo;</TD></TR><TR><TD CLASS="quote">2.5" on t/b side and 2.0" on turbo side</TD></TR></TABLE>

+1

 

2 inch

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by coneheadsracing &raquo;</TD></TR><TR><TD CLASS="quote">personaly i wouldn't go much bigger then the size of the outlet on your turbo. Exhuast, definetly 2.5, not gonna hurt anything by going bigger.</TD></TR></TABLE>

i would think that you wouldnt need to go bigger than the bore of your tb. but thats my o.o2

EDIT:
keep the hot side the same as the turbo discharge, and the cold side, the same size as the tb.

 

i also wouldn't go bigger then ur throttle body

 

There is always a balance.

For the charge pipes, the balance is flow vs. volume. The larger the pipes are, the less head loss (pressure drop). For exhaust, the balance is flow vs. noise level and fitment. Go bigger means go louder, and you may find it difficult to fit a 4" downpipe and exhaust.

Charge pipes are generally made too large. While the staple size is 2.5", this size will flow enough to support over 600 horsepower. 2" is actually just fine for up to 350. I run the same turbo you are going to run, and I use 2" charge pipes and 2.5" exhaust, with a full exhaust, cat, and chambered muffler, and lag is not bad.