exhaust ideas

[nemesis]

I was wondering if anybody ever tested the difference between stock exhaust manifolds, short tube headers and long tube headers for the gas mileage. I know that anything but stock exhaust manifold will gain more power, but what about the gas mileage??

Me thinks long tubes will get better gas mileage, because they'll help out low mid torque, but I've been wrong before, and I'll like to hear your opinions.

[aerohead]

use the Search Ecomodder tool to dig up related threads on exhaust-related mpg.Hundreds of lines have already been posted on this topic.

[Tygen1]

It wont' hurt mpg, but it will never pay for itself in savings, if there are any that can be measured. I installed a 4-2-1 header on my car after the stock manifold cracked, that's a good excuse to buy something that won't pay for itself. I definatly didn't see any drop in mpg. Mid range power is better which helps on Pulse and Coast routines to get to the target speed quicker. In summary, the savings is a fuzy number. If you enjoy the extra power and have the money, it won't hurt your mpg...

[nemesis]

The reason I thought of exhaust, is because of the intake, long runners give you more bottom end power ( better mpg) and short runners give you great top end hp ( worse mpg).