View Full Version : Exhaust sizing....
Blackcoog
07-25-2003, 02:01 PM
Who has what and whats the best to get? My borla is way to small for my car so I'm looking for the best system to upgrade to if I plan on going with FI later on. Kinger what are you running right now? I thought it was a yodude correct? What size piping? I'm looking at the 2.5'' and 3'' dual yodude system. Will 3'' be too large if I don't have FI on the car?
Kinger
07-25-2003, 04:12 PM
I have a full 2.5" from the y-pipe back with straight through perf core mufflers. It does spilt into 2-2.5" in the rear for the dual outlet look I wanted with Roush tips. 2.5" would be fine on a hopped up 3L I would say.
Blackcoog
07-25-2003, 04:15 PM
Would it be too small for a turboed cougar though?
Here's my Y-pipe and cat, 3":
http://www.fastcougar.com/forums/attachments/3LProject74.jpg
Then to a Borla Pro XS (http://borla.com/proxs/pages/muflroff_ctr.php?cartID=20030725135015) 3" Offset/Center Muffler, and yes, I know their inner diameter is only just over 2.5"...
Then a swedged reducer to mate to the rest of a stainless 2.5" "Trubendz", dual polished tip (very Borla-like).
Better than my stock 2" cat, and 2.25" Borla, I'd say...
Jagular
07-26-2003, 12:13 PM
I run a speed shop here in Indiana. I bought a 3" Pro-street spin tech muffler, high flow cat, and a buch of mandrel bends and made the 3" kti that I have. Man does it work great and sound good too. Its deadly quiet at idle, but as soon as you get in the throttle she roars. I can do the same kti for you for about 350.00 or can sell you the parts for 275.00. If you have a MIG or a TIG welder you can do it your self. 3" is the only way to go for a FI coug.
Blackcoog
07-28-2003, 03:42 PM
How is the sound compared to the borla Dan or haven't you installed it yet? I'll get the same thing if the sounds is similar to the borla's.
So here is what you have then right:
MSDS headers, MSDS y-pipe, 3'' cat matted up to the y-pipe, 3'' Borla muffler, 3'' to 2.5'' reducer and the rest is a 2.5'' trubends exhaust? So basically your trying to run 3'' until the split and then have 2.5'' dual outlets. Sounds like a good plan. Did yodude have to customize your setup then or did you customize it when you got it.
Thanks,
Chris
Customized when I got it. It's a bastardization of Heather's Trubendz, since I'm trading her her 1 1/2 Trubendz systems for my complete Borla (long story). Anyway, I haven't installed it yet, the muffler and piping that I needed just showed up at my place, and but I'm on the west coast on travel all week! <sniff> Maybe next week sometime... Dunno. All I feel is the engine just begging to breathe- Think I'll have to scrap the KKM next...
EDawg99
08-15-2003, 11:42 PM
hey, if u do change your exhaust, would you be interested in selling your borla, if so, i'd be willing to buy it. if you are, pm me or email me at edawg1984@hotmail.com.
thanks.
-Eric
Blackcoog
08-26-2003, 05:28 PM
Hey Dan would it be a bad idea to run 3'' piping up to my borla split.
Lets say I want to pretty much run a 3'' single exhaust but I like the dual look. I'd run a 3'' exhaust until the split and then run two pipes with the same amount of volume that one 3'' pipe would have.
Volume of a pipe: Pi*R^2*height
Two 2.25" pipes 1" long would be: 3.14*1.125^2*2 = <u>7.94in^3</u>
One 3" pipe 1" long would be 3.14*1.5^2 = <u>7.065in^3</u>
So technically 2.25" is too big and 2.5" would be way too big.
Two 2.5" pipes 1" long would be: 3.14*1.25^2*2= <u>9.81in^3</u>
Damn I might just chop up my borla and run 3'' to the split and see what happens.
Chris
EDawg:
I'm trading my Borla with Heather S. for her 1/2 Trubendz systems. I'm cutting and pasting the system together along with a section of 3" stainless pipe, the Borla Pro XS, and the Carsound hi-flow cat.
Chris:
May not be a bad idea! I think that the toughest part would be to get 3" piping bent like you need it, and still maintain clearance with all the suspension components and fuel tank. Many $$$.