trying to decide on wether or not i should run hi flow cats or just run it w/out cats.. I have decided to run 3" spintech sportsman exhaust on my set up with bbk LT.. this is my combo.. 331 sportsman block, 8.8:1 compression, forged internals 185 AFR heads, v2-sq w/ stock pulley, AFM power pipe 80 Pro-M meter, TFS track heat intake, crower cam proper fuel system I have alot more but I dont think it will help everyone out w/ there opinion.. What do you guys think, Hi flow cats or no cats? Thanks everyone !!
I can tell you this since Ive run both with cats and without. I noticed no gains, but she runs way cooler without the cats. Loss 2 lbs of boost due to the reduction of backpressure (without cats) but no loss or gain. peace
I have actually seen dyno numbers where adding cats to a supercharged motor adds torque and horsepower all accross the rpm band. Ive also talked to a few guys who have seen a mph or two increase by using cats! I think alot of it has to do with the actual exhaust setup..in otherwords what manufacturer, size, etc of the piping. I dont think this would apply to every car, however its an interesting test. Here is a link to a cats vs no cats on a s/c 'er car : http://www.corral.net/forums/showthread.php?s=&threadid=431842 Dan
thanks for the imput guys, anybody else seen or heard of any thing like this? Whatta ya guys runing, cats or no cats? Every single mustang I've own I've had no cats, so im kind of scared to hear what its going to sound like cuz i LOVE the way the soudn without those damn cats on..
I was running a MAC Prochamber when I raced at the track. On the dyno I had a BBK Cat-Hpipe. If I ever get a motor in the car, I will end up dynoing the car with and w/o cats just for ****s and giggles. Dan
I would run it with cats. I am running my car with cats and i can run it on the street because it passes emissions and sniffer tests. Also, since there is very little, if any, loss in power due to using them, there really is no reason not to. And it keeps the air breathable to, though that is not all that popular an opinion among us HP junkies.
on a stocker, when u take out ur cats, it does help you out a lot.. but my car is far from stock.. The only reason why i would use them is to help create velocity, more tq... do you think this will help it out?
I personally would think it would be the the exact opposite. On a near stock motor, it should require more backpressure of a high flow cat. If it was straight through, then you would be losing torque, not gaining. Dan
well a stock car has more tq then hp in the beginning, you seriously gain quite a bit of hp when u drop the cats an you come out with a mean sound.. I know this from experience.. It does increase hp but does drop the tq numbers.. On a stocker.. On a stroked out motor w/ a power adder, i think having cats isnt gonna be a big deal, most people think im crzy for asking this question but its a reasonable question in my eyes.. Im running 3" exhaust from LT's.. Thats pretty big in diameter...I saw that one post on the coral forum, but would like to have more imputs.. So far everyone says run w/out cats.. I say the opposite.. What do you guys think?
bought the bbk h-pipe with cats already installed and it works great. passes for emmisions and inspection etc... i had hem off b4 and i coudn;t tell any difference with them on or off, cept now it's legal
94 Mustang GT Dyno tests Pypes 2.5" system with X w/o cats V-Force Mufflers 229.6hp @4600 rpms Pypes 2.5" system with X w/Pypes mini cats V-Force Mufflers 227.1hp @4600 rpms Cat system passed emissions like a stock GT would.
