ORIGINAL: Dudelive
If the pipe seals properly and there are no leaks you will not have the performance from that setup that you could have. It is the same as porting and polishing heads on real to life size cars, it helps the exhaust escape smoothly thus causing a vacuum effect to allow more out faster. The faster you can get ALL the exhaust out of the enging the faster it can get more in and start over again. It has to get in fast and out fast in order to have the best performance. If you are not looking for the best performance then you may not notice a difference.
I don't run nitro but what I have explained above is the way it should be. If I am incorrect then one of the some of the experienced nitro people will correct me. Thanks
Thanks
Dudelive
Exactly!
If you use that header, the car will run, but you will not see the same power or RPM's as you would if you had a matching header.
Like Dudelive said, it's how fast your exhaust gas flow rate is that dictates your intake rate. Haveing the headers not matching will slow the exhaust gas down considerably.