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69 fairlane 351w 12.94@103mph before M&M.. [email protected]
always in search of more HP and faster ET'S

http://www.dragstuff.com/techarticles/vacuum-pumps.html

I was told that 5000 rpm was about the max that I should be turning them and I was turning mine 7000+ rpm. When I switched over to the 460 I made a small pulley to fit the Fluidamper that runs the pump around 50% to 60% of crankshaft speed.

I ran a 4 vane Moroso pump with a relief valve on it when I first got the 460 running and it worked awesome. I burnt 3 pistons in it right away and never got the ring seal right after that because of 2 half-assed hone jobs to re-ring it twice after that.

I just got it running again with a different block that has a fresh, quality bore and torque plate hone job so the rings should seat right this time. I've got a 3 vane pump on it now without a relief valve (I'll get one if I need to) but I haven't run the car at the track yet.

It pulled 10" of vacuum at 3000 rpm in the driveway with about 5 minutes of runtime on it, so I think it's going to pull some good vacuum when the ring seal tightens up.

I can't tell you for sure what it was worth for power since I had so many other factors with breakage and whatnot, but it kept gaskets in it real nice and I was never able to run within a tenth of it's best time after I pulled the pump off....even after switching to alcohol for a while.

The reason I went with a vacuum pump in the first place is because I started running mufflers and lost the ability to run my traditional pan evac system into the collectors. After looking into running a pump I started hearing stories of power gains, I didn't look into a pump originally because I was looking for a power gain....I was just trying to keep gaskets in the motor.