gutting CAT , TQ loss debate!

[Firehawk N Wv]

My buddy and I have both gutted our cats on our cars. I have 01 bird and he has a 00 bird. I know its different for each and every car. He says it causes a loss in TQ, but I dotn think it does or at least not a noticeable amount if so. What is the generalization of doing this mod???? I'm leaning towards gain in 3-5hp but a mere loss in tq , unoticablly. Well let me kwno your thougths guys, thanx!

[99v6cam]

You don't lose torque, in fact you may even gain torque. The difference you notice is the rpm that the torque is at. The torque will come at a higher rpm but will NOT be lost.

[camaroman1181]

when i had mine off, i lost a good bit of pull below 3500 rpms but gained power up top. it definately helped the car breathe above 5000 and no longer sufficated itself as bad. course i have a 3.4 so what you experience will probably be different...

[mjparme]

You are removing a restriction so backpressure will drop, this increases horsepower. You aren't going to a bigger diameter pipe or anything so your exhaust gas velocity isn't going to drop. It will probably increase due to the cat not being there slowing it down.

So you are decreasing backpressure and keeping your exhaust gas velocity the same (or maybe even increasing it). You will NOT see a torque loss, you should see a torque and horsepower gain throughout the RPM range.

The torque shifting up in the RPM range would only apply if you were increasing your piping diameter. It would take a little longer to produce enough exhaust volume to get your gas velocity to an optimal level (and if your piping is to big it will never reach an optimal level).

[ April 21, 2005, 09:44 PM: Message edited by: mjparme ]