HiPerf2000

iTrader: (2)

Has anyone put a Flowmaster on thier 6.0 Chevy?? I Was looking to run cat back duals, straight out the back with a 40 Series Delta Flow (Delta flow lessens cab noise). I am going to buy the Flowmaster, and have a local shop custom bend and run the dual pipes.

My question is: i have a choice on the dual outlets being 2.25 OR 2.5 Is anyone running a similar setup?? What size is better for noise/performance??

CigDaze

I had the same Flowmasters on my Ford 351 Bronco and I tried both 2.25 and 2.50 pipes. You have a little more cubes than I had, but the 2.50's worsened my milage slightly and didn't provide any back-pressure. The 2.25's were perfect for my application. 5.8 vs 6.0...not too far apart.

28SS

The 2.5 or 2.25 will be fine the cat will keep enough back pressure in your system

HiPerf2000

iTrader: (2)

So if the Cat is the restricter(Backpressure), It doesn't matter which size outlets i choose???? So that means the different sizes are only for exhuast systems not using cats to create back pressure??

DanL

I'm a Flowmaster distributer. Use the 2 1/2's. Just from the look out the back, you don't want wimpy pipes. Pipes that are not mandrel bent squeeze exhaust flow down 30% versus straight pipes. I can sell you a pair of aluminized non mandrels for about 50 bucks. I have 2.25 mandrel duals for your truck for like $85. Nice angle cut tips are arount $12. each. Dan

DanL

Cats flow pretty freely. Don't think they are a big source of back pressure. Take the kid with the Honda who plumbs the car with 2.25 pipe, hi flow converter(no such thing)
and a stainless polished straight thru muffler. Instant bog from a standstill. The low exhaust pressure and large exhaust volume basically create a vacuum in the system. Backpressure is a source of bottom end torque, but now its gone.

bsag

i went with the flowmaster cat back single out kit its plenty loud enough. I wanted the factory look so im not bothered by MD police.

Cord

iTrader: (2)

I went with the 40 series delta flow on my S-10. The truck is quite loud on acceleration, but quites nicely when cruising. You can hear the truck from blocks away and through buildings. The sound is OK at idle, but other than that it's rather buzzy. That's proably due to the V-6. The muffler also has a hollow sound to it that I'm really wild about. Most people (even some gear heads) just say that I need a muffler. What ever you do, don't waste your time on Flowmasters universal kit.

liquid asset

I have 2 - 2 chambers [ The 6.0 has 2 cats] it is pretty loud but sounds mean I turn mine down at the muffler, it sounds and looks better , chrome tips are out

boot

hi-perf-2000 Deffinatly go with 2 1/2" pipe .Your 6.0 puts out a lot of power compared to older trucks . I assume you are using 1 muffler with 2 outlets ?

DanL (sorry dude ) but I have to disagree with the cat thing . I drag race a lot and a car ,say a 5.0 mustang ,with cats ,will get slower every time it runs if it runs back to back because when the cat gets hotter it swells shut ! It is very restricted the hotter it gets . And they do make high flow cats . Granted some are not as good as others . I actraully had a cat get hot enough pulling a big mountain out west with a heavy load ,it was 100 degrees out and the truck just shut off at 65mph going up a big hill ! Looked under it and the pipe was glowing cherry red from the engine back to the tail pipe . The dealer said cut the cat off.It was like night and day with out the cat .Picked up almost a mpg too !


[ 02-05-2002: Message edited by: boot ]