backpressure helps the little 4 cylinders make low end tq and hp, but only hurts one in the upper rpm........but remember this, valves are hot after you turn off your car....on a cold day, if you are running only a header, that cold air can easily make it's way to the valves and cause them to warp over a relative short period of time.......not gonna happen every time, but it's VERY common....that long exhaust will keep the cold air from making contact with the valves........
cutouts (electronic or manual) are a good compromise but still illegal if there are any noise ordinances and don't think cops don't know about them....they're old technology.....and they can also use that as an excuse to search your car since it gives them probable cause (you're "cheating" with that, why not other things)
at the very least, it can be aggravating
cutouts (electronic or manual) are a good compromise but still illegal if there are any noise ordinances and don't think cops don't know about them....they're old technology.....and they can also use that as an excuse to search your car since it gives them probable cause (you're "cheating" with that, why not other things)
at the very least, it can be aggravating
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