hey guys im in the process of a turbo build on my B18c in my 98 GS-R...Im looking into exhuast and im not gunna lie my budget is getting SUPER tight

I plan on running 8-10lbs of boost and make about 330-350 whp on a fairly stock b18c except for arp head studs and a VictorX intake mani.

rite now i have a 2.5" cat back with a stock cat...

if i get a test pipe to fit that and a 2.5" down pipe will i be okay for the numbers im looking to hit or am i going to run into some back pressure problems?

heres some more info about the car

gt3037r 60 trim
550cc RC injectors
walbro 255lph fuel pump
custom made ramhorns
tial wastegate
blitz bov
500hp rated innercooler

any help is good please no bs

Thanks!

 

you should be fine with a 2.5in exhaust once you pipe out the cat. I mean, a 3in exhaust would get more power, but i doubt a 2.5 would be restricting it a lot. And if you're not worried about getting pulled over, a nice muffler like HKS, Apexi or GReddy would gain some hp's over a conventional stock style muffler.

 

Kinda interested in this too. Cant really afford the 3" right now

 

yeah its got a nice muffler on the 2 inch catback its basically silent at idle w/o the turbo and sounds awsome....one thing i forgot to throw in the description is that it has two resinators big detail to leave out i suppose

 

bump wednesday

 

2" is getting kind of tiny. You definitely will not take full advantage of the turbo.

 

its 2.5"

 

I am running the invidia g300 with 377hp at 8100 with an 83mm b18c ctr cams. I know its a tad smaller than a 2 1/2 pipe. The worst is the resonator just about all the brands I have seen get really small like 2" at the end there, if you look inside. I am running 12psi with a g35, clutch was slipping so im not sure what the max hp would be. I am in the process of putting a new clutch in the car and will take it back to my tuner next week and find out. I will probably just end up getting a thermal 3" in the near future.

 

any chance you can get your hands on at least 750s? 400 crank hp with a .6 BSFC will require 750cc injectors at an 84% duty cycle

84% of 400 is 336 which is around the wheel hp for 400 crank

550cc injectors are designed for around 300 crank hp or 255whp

you can push them harder obviously but it's not ideal or a long term solution

 

I have a 98 GSR with a 3" downpipe and 3" exhaust with a 30" resonator that dumps right in front of the rear tire with a slight turn down. The resonator ran me about $40 I think, and then about $80 in pipe if I remember right, but that wasn't including the downpipe. I like the way it actually turned out sound wise, it's not to loud but its not quite.

 

i plan on running about 70 psi line fuel pressure to make up for the small injectors...thatll put me rite around 300hp with only 80% duty cycle on .6bsfc

 

i was thinking about cutting off the resinators and running just a strait pipe where they used to be....hopefully that will solve some back pressure issues

any thoughts?

 

whered u get all the materials?

 

here you go:

http://store.kteller.com/kteller/kte.../i-402955.aspx

 

alright how bout a link for a fitting kit...i can find all the single sold peices but a kit would b pretty dope

 

Can you be more specific? Fittings for what?

 

the exhaust flanges bro

 

2.5" will be fine, no need to upgrade to 3" if money is tight. Just put a test pipe on it to get rid of that cat, no need to cut out the resonators.

 

The word "fitting" is not a synonym for "exhaust flanges". So the wasn't quite necessary.

I have never seen a kit that has the flanges to weld on to that exhaust. If you want to go through all the work to weld flanges on for no reason be my guest, but why don't you just weld it together? Way eaiser, more simple, and cheaper, like you said you wanted.

 

That kit comes with the flanges and hangers.

 

http://www.mandrel-bends.com/catalog...-43/honda-108/

This is a place that is local for me kind of, but they do ship.

 

Didn't see that. Good catch.

 

Oh forgot to say they also have a wide selection of flanges, and numerous other exhaust and pipe fabrication products.

 

alright not to change subject but how bout muffler decisions

want something relatively quiet

any ideas?

 

When I thought about running a muffler, I was thinking about just a 3" in and out generic oval muffler with a turn down tip. After we got done with my exhaust, I was happy with the way it ended up sounding. It's not too loud with the 30" resonator in the middle.