Hi flow cat's

[hidesertwheelin]

Do hi-flow catalitic converters really work? Do they flow enough to make more power? Mine works fine and but I am wanting to run a 3" hi-flow cat and 3" flowmaster single exhaust on my 90 suburban. I don't want to spend the money on the cat if it's not worth it. Thanks for the help.

 

[Fierospeeder]

the stock exhaust has very low backpressure. And backpressure is needed to help the engine run properly. And some instances help function some emission devices.


If you want a lot more performance, i would look into removing the old stock exhaust manifolds and getting headers.


Theres a post not too long ago about a huge debate weather or not exhaust systems work. I can see if i can find it.

 

[dirtwarrior17]

backpressure is tricky because you can't just say this system has 3 psi of backpressure... it is constantly changing with the rpms.... at idle any stock system will have less the 1 psi.

 

[Fierospeeder]

3psi is the highest it will ever get unless you have other issues in the exhaust.


http://coloradok5.com/forums/showthread.php?t=116788

 

[dirtwarrior17]

i saw a two guys garage where they bent the tailpipe almost shut and got it up to 14 psi... sounded like a go cart. lol

 

[Jonny-K5]

if your going to the trouble of putting the flowmaster catback kit on, i'd go with a high flow cat at the same time. especially if your cat is a few years old. you can pick up a high flow for around 50bucks.

i think any exhaust upgrade on a stock engine will only produce minimal gains in performance. i've got good headers, cat, flowmaster and madrel bent exhaust, barely notice a difference if any. the main reason to do it is for better sound. in the near future i'll be putting in a stronger motor that will need to breathe better, so i had some justification in throwing all the exhaust upgrades at it. that and a cracked manifold to put the mods on the front burner.

 

[camiswelding]

And I just happen to have a hi flo hedman cat 3 inch... with 250 miles on it ... 50 and the ride...
(I beg to difer with the other poster....you wont get a high quality hi flo cat for 50.00 anywhere)

cam

 

[Jonny-K5]

i think i got mine for less than 50. it was from mudfrog. i forget the brand, but its the most common one i see around at the muffler shops. im sure they cost more if u get them thru a shop.

 

[mini_mull]

check www.performance-curve.com . He's a member and a vendor, can't remember his screen name right now though.