Vacuum Pumps
12-23-2002, 08:06 AM
#11
Registered
Thread Starter
Originally posted by jdnca1
Agree with blown1100, in a high hp application you will see a benefit, but just more to maintain in a marine engine. I watched my engine builder dyno a 500" pro stock motor @9400 rpm. On the last pull power fell off by 60HP, initially he thought he'd lost a couple of valve springs. Turned out the vanes of the vacuum pump turned in their notice, had to tear down the engine to get all of the pieces out. It was amazing that the pump was worth 60hp though.
If you ever get the chance to see a 500" Pro stocker dynoed...jump at it, very very impressive. This one was "down" on power, 2 yr old technology, and "only" made 1285HP. Valve springs lasted 2-3 pulls and pulls began @7500 and ended @9800
Agree with blown1100, in a high hp application you will see a benefit, but just more to maintain in a marine engine. I watched my engine builder dyno a 500" pro stock motor @9400 rpm. On the last pull power fell off by 60HP, initially he thought he'd lost a couple of valve springs. Turned out the vanes of the vacuum pump turned in their notice, had to tear down the engine to get all of the pieces out. It was amazing that the pump was worth 60hp though.
If you ever get the chance to see a 500" Pro stocker dynoed...jump at it, very very impressive. This one was "down" on power, 2 yr old technology, and "only" made 1285HP. Valve springs lasted 2-3 pulls and pulls began @7500 and ended @9800
