1INSANEGTO

iTrader: (13)

I have a 408ci F-1R combo. I am running a Custom Stepped ARH Headers 1.750" to 2" with a 3.5" collectors. I wanna use a Y that will connect to my 3.5 collectors and turn into a 5in Oval and run one single 5in oval out the back.

I wanna do just like the pic says. I know on a F-body you guys have a Y pipe how big is it and what are the after market ones? I posted on RCC thread and got different feedback but I wanted to see if anyone has done it?



Pic of the Y

NoGo

iTrader: (2)

Used to run a 3" collectors to a 4" Y to a dump. I didn't make any more power so I switched back to a 3" collector so I could quiet the car down.

The smaller diameter exhaust just moved the inlet boost up a smidge. The end result is that I made the same power with the 3" exhaust as I did with the 4" exhaust. Albeit the boost with the 3" exhaust was a smidge higher.

You can go 5", but it may not make that much of a difference HP wise. You will probably make a similar number to a 4" or 3" exhaust it will just move the inlet boost around a little. Even 5x2.5 oval exhaust is tough to stuff under a car. Just my .02

TurboAv

iTrader: (6)

That motor is going to move a lot of air though. I would maybe even go with their 6" oval. I'm not a math guy, so take what I say with a grain of salt.

Bob@BruteSpeed

iTrader: (16)

http://www.kookscustomheaders.com/show.php?pid=189
http://www.kookscustomheaders.com/show.php?pid=190
http://www.kookscustomheaders.com/show.php?pid=191

The ones above from Kooks headers are pretty typical of what you will find in available sizes for the f body. Bob

stevieturbo

At 5"....thats going to be bloody loud !!

JAX04

iTrader: (17)

ok, i did this math insane, and the 5" oval only offers the same pressure drop as a 4.25 diameter round pipe.

i realize it may have the same area, but we are concerned with cross sectional area and pressure drop which is basically way of saying how much restriction it has.

Unless the formula i used is botched, and i did it wrong, but i did it twice with the same result. Im not trying to tell you the wrong thing, infact, if im wrong, id love to be proved wrong, so that i know for future, so i can help more accuratley. But if my formula i used is correct, Then that 5" oval is only as good as a single 4.25 diameter round pipe.

http://www.engineeringtoolbox.com/eq...ter-d_205.html

1INSANEGTO

iTrader: (13)

This is what I wanted to see. So Bob your big hp guys running your blowers are still running the Y pipes. Do you think I will be fine with how I wanna run this setup on a GTO?

Bob@BruteSpeed

iTrader: (16)

Yes, f body's have run into the high 8's with a y pipe. I don't see you having any problems. Bob

1INSANEGTO

iTrader: (13)

Well the muffler is rated at 93db........Not sure I am interested to hear it

stevieturbo

It's impossible to give a noise rating for any muffler.

They dont know what's going into it. And a static reading, without detailed measurement data, is also meaningless.

FWIW, standard motorsport testing is 3/4 max rpm, 0.5m from the tailpipe, level at a 45 deg angle.

And I can tell you, 93db under that procedure, is very damn quiet !!! My own car hits about 104db under that test.
Most motorsport tracks in the UK insist on 98db ( damn neighbours !! ) with some venues being allowed up to 101-103db on occasion.

Fortunately the drag specific tracks havent had any such restrictions imposed on them ( yet )

1INSANEGTO

iTrader: (13)

These are rated for people who have restrictions at the track. Here is the mufflers. http://www.spintechmufflers.com/muff...es/cat_20.html