64 Custom,
Bolt on the carb and test the exhaust with a CO analyzer. That's about the only way to really nail things down. You can work your way down on jet size until it gets to about 2% to 3% CO under wheels-in-the-air unloaded condition with the motor turning about 2000 rpm. You can start out with the stock 72 jets. I ended up with 70's in one of my early engine combinations using a 600 w/vac secondaries on a 292.
63 Deuce,
Any Holley carb that works well aspirated on a given engine will be great for a blow-through turbo. I've got several buddies here in the Phoenix area that have done that over the years on other make engines (Pintos, Vdubs and Corvairs come to mind). Doesn't matter if it's a vacuum or mechanical secondary unit. The signal to open the butterflys on the vac models is taken from inside the carb, and it's a balance between signals that determines how much and how fast they move. The turbo only makes more air go through, so nothing really changes. Kinda like putting a 600 on a big block. They work great unless the motor needs more air than the carb can supply, and then it just tops out and doesn't go any faster!
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David
newbie #4153
