View Full Version : Will overdrive pulleys hurt my engine?

10-28-2002, 07:00 PM
Overdrive pulleys can make your supercharger go out faster and put more
stress on your engine. These pulleys can make the supercharger spin up to
15,000 and 16,000 rpm, which is higher than the factory rating of 14,500 rpm.
But, many superchargers live at 15,500 rpm on daily driven SC/XR7’s. Even
Eaton Corp. has admitted that 1000rpm over the factory rating, while not
suggested, will not ensure the death of your supercharger. It is a fact that
overdriving will shorten the life of the supercharger, but these superchargers are
very stout and can take more abuse at higher power levels.

Overdrive pulleys will add more boost though, and this increase in boost
translates into higher cylinder head pressures and temperatures. “Boost” should
really be thought of as “back pressure” within your engine. Higher back
pressure can make your 3.8L more susceptible to blowing a head gasket. That
is why you should always upgrade your exhaust to a higher flowing aftermarket
headers, down tubes, and a larger diameter cat-back system before installing an
overdrive pulley.