does removing the catalytic converter add HP? Options

[nate95]

Hey i was just wondering if i were to remove the catalytic converter if it would add any horse power? or what about getting a "Y" pipe before the cat. so i can still have the cat. but have it go straight out when i want to race?

[Negative]

On a NA 7afe, removing the cat will result in a couple (not 5- 10, more like 2 - 3 ) of gained hp, but will also likely result in a slight loss of torque. Naturally aspirated engines are designed to run with backpressure so removing that backpressure really doesnt help you all that much.

I agree from my experience with actually doing this. No Dyno numbers though.

little off topic...i just got my headers on last night ...i don't really feel any difference(except the ricey buzz) at regular(low rpm) driving but when i floor it to mid rpm it seems to not have much torque but there is a pull...then again i won't really know if there's hp's added unless i go the dyno...

Wait till you feel the difference at high RPM - the car now will pull through about 6500RPM. I did notice a decrease in low end torque but I was just spinning wheels at WOT anyway so a little low end loss in favor of top end gains was worth it. Lord knows the stock 5s could use some top end LOL.

Man - I can remember when I was the only person I knew with a header on a 5S Celica. Now it seems like everyone has one and my formerly beautiful SS Headers are now a very ugly collection of golds, purples and blues with a little ashy look thrown in for more bad looks. Oh well it's all about to be a moot point when the Turbo goes on this summer anyway.