I read somewhere that the length of the exhaust can affect the performance of the car. We have a 2004 Cavalier with the 2.2, all stock. Right now the exhaust pipe stops just past the firewall. The track (3/8 mile dirt) rules state that the exhaust has to be run just past the driver area. I will extend it to be legal and to be safer. My question is how will it affect the performance of the car? We just got the car and haven't been on a track with it yet. Thanks
We run them back past driver 2.5 inch and no problems with power restriction
Do you just run straight pipe off header? Or do you run a cat?
The pipe is cut about 2-3 feet past the stock manifold. Rules prevent headers and such. All stock.
I did some testing. Stock 2005 L61 base Cav. with polished throttle body, a 4-1 header (RK Sports I think), catalytic converter & muffler.
I started drilling 1/4 inch holes in the bend where the exhaust pipe turns to head back under the driver back seat. 3-4 holes stemmed to make a bit of difference to the butt dyno. I cut the exhaust off there & it killed performance. I put it back.
I have not noticed any difference with or without the cat but its going to take some real testing to determine if that is the case.
Removed the muffler made the car louder & saved, what 15 pounds, but other than weight that probably didnt help the engine breath better.
Im thinking the exhaust for a stock L61 needs to be 1/4 bigger in diameter & one of these days I may get around to testing that.
tazassape wrote:The pipe is cut about 2-3 feet past the stock manifold. Rules prevent headers and such. All stock.
I finally gave in and installed a camouflaged header. No dyno information but picked up speed on the straightaways.
If you get the exhaust too short or too big 3'' it hurts bottom end performance. Basically restarts or the original start of the race. Had 3' that stopped right behind the driver at the end of the tunnel. Went back to 2.5". We were loosing 2 to 3 car lengths on a restart