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vacuum gauge

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tinman58 said:
Darrell, What boost do you get? I get 6 to 7 lbs.
Click to expand...

I'm getting 5, or just a bit more. I'm still running the standard pulley on the blower, though I do have the big boost pulley.
 
startech47 said:
Looks like a port for PCV.
Click to expand...
I kind of doubt it, at least not a successful one. PCV requires a good deal of air flow, so you need passages & fittings that are somewhat larger than are practical into that relatively small tube.

If I was going to use intake vacuum for PCV, I'd probably do two larger fittings, one into the "box" on each end.

But that still doesn't address the main problem with using intake vacuum : The vacuum goes away just when you need it most, resulting in positive crankcase pressure and oil blown out past the seals. I'm thinking that exhaust evacuation would work better (but haven't had a chance to try it yet).
evacsysteminstallsy2.jpg
 
Not mine though. I got the idea from Joe Alexander, and it's written up in one of Kas Kastner's recent books. The concept has been around for quite awhile it seems, with the circle track folks who seem to believe that holding a partial vacuum on the crankcase promotes better ring sealing and produces more power.

Joe sent me a photo of his setup, but I can't seem to find it on this computer.
 
It's not a new idea. We used crankcase systems in the the 70s in our muscle cars (with mufflers). Still have a couple of one-way valves around here somewhere.
 
Just back from two days driving the Skyline Drive...

Thanks to all for the feedback on the vacuum gauge connection.

Since I only got interested in this because of the Moss Motors video, and not because of any perceived problem with my car, and because I'm still not certain if the plug in my manifold will come out without a problem, I think I will leave well-enough alone and not fool around with it.

At least now, thanks the the feedback, I know what the plug is for and where I would attach a vacuum gauge if I ever needed to.
 
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