I'm currently looking at replacing the stock exhaust on my 85 gsl. I'm looking at a used set up that came off an 83. I decided to check prices of new and noticed that the 83 and 85 headers had different part numbers. What's the differnce in the two, is there any way to get it fit.
Also, my rx7 is my daily driver. Would new exhaust effect drivability any, how much increase in power, what about gas milage.

Thanks

 

On a stock car, the exhaust probably won't affect performance as much as it could if you had other mods done to your car. You will notice some difference and it will sound different too. Not loud and noisy, just healthy.