High-Flow Cats

Does anyone know anything about high-flow catalytic converters? Some say you lose alot of back pressure but better sound. Good idea? Better sound on a 99 v6 with flowmaster 40's with straight, true duals(no h/x pipe) and cats?

Yea your gonna lose back pressure of stock but that's the point. I honestly don't buy into the whole if you have no back pressure you lose torque.

Don't run straight pipes. There's a reason why companies make h and x pipes for mustangs, even the 6 shooters. And yes, the whole point is to make things less restrictive, and reduce some back pressure. But there is a line that shouldn't be crossed, like adding a 3" system to your car. Now that's over kill, and will obviously lose torque.

is there a site where i can find info on differences/affects of straight pipes vs h- or x-pipes and also affects of normal cats, high flow cats, and no cats. i currently have 3" straight pipes to my flowmaster 2.5" exhaust. i learned after the install that this may not have been my best idea yet, but i have not returned to the mechanic who told me it would improve the car (and i now research before i change)!

is there a site where i can find info on differences/affects of straight pipes vs h- or x-pipes and also affects of normal cats, high flow cats, and no cats. i currently have 3" straight pipes to my flowmaster 2.5" exhaust. i learned after the install that this may not have been my best idea yet, but i have not returned to the mechanic who told me it would improve the car (and i now research before i change)!
What year is your car, what size motor, and what exactly was done for exhaust work?

all that has been done to my 95 gt is a K&N, 3-inch pipes run straight back from the headers to the exhaust, and Flowmaster mufflers (not sure what type). the cats were taken off and left off. i get some putter when the car first starts and i give it the gas (due to lack of backpressure) but it goes away, and it doesnt seem to affect throttle response. when i replace the heads and headers later, i will replace the pipes with xpipes and high flow cats (good fix?). thanks.

high flowcats are nice. you may wanna try what i did. i've got flowtech shortys to start with. then i ran 2 3/4'' pipe back to a duel inlet/duel outlet high flow cat. ran 2 3/4 back out of it and into 1 chamber flows. and ended with 3 1/2 tips to give it a deeper tone. its load as hell! , yet sounds damn good. doesnt sound like your every day ford. just for the record this is on a 1990 f-150 with a 302/5spd. i have to say though that i have had 1 problem with my high flow cat. i blew the front screen out when i was racin a c10 so now it rattles around in there. note to self: dont turn 2nd gear up to 6 grand.

Alright, thanks for your posts. Personally, I don't think they would hurt. So if I can get em cheap, in your opinion, should I get them? By the way, I might get a mom & pop shop to make me a custom h pipe.

if it were me, and i wanted some decent cats for cheap then i would just buy 1. a duel inlet/duel outlet cat cost around $20 more then a single inlet/single outlet cat which is gona cost around $75 already. i payed $90 for my cat. you will get more room under the car, better ground clearance, and less back pressure.

how bout no cats.? cherry bomb ur exhaust dude, straight up pwr.

Cherry bombs, ewww! There's so much better out there for Mustangs, why would you ruin it with a cherry bomb?

yes, go full length headers if you don't have emissions laws, and skip the cats too!
deff. go with an X pipe over an H pipe, and lastly get a muffler that won't get the cops attention. the 3-5 hp you lose will be worth it when you creep by quietly.