Need more vacuum

[bobdoo]

We have worked on carb adjustments and timing. We need a little more vacuum to meet tech. Will small valve adjustments help?

[Fox_hunter42]

loosen the valves slightly. If you have a solid lifter cam. If hyd. it won't help. turn idle speed up a touch also

[fast_crew]

Can you run a choke cable setup into the dizzy, through the vac advance opening to move the pickup coil? This would allow you too advance the timing even more when needed to pass tech...as far as valve lash yes loosen the intakes up a little but will increase the vacuum aswell.

[let-r-eat]

How much short are you?

[bobdoo]

We are a good 2 points short

[Fox_hunter42]

if you do not have an idle speed rule also turn it up. loosen valves a little, not to much. should get you very close

[DaveBauerSS6]

Lock out the mechanical advance in the distributor.

[lilsumo]

You can run Rhodes lifters, they can give as much as two points of vaccuum

[fastford]

the new Rhodes lifter , they claim , can give you up to 4lbs, I never got over 3lbs though, when we were doing the vacuum engines, we found a 650cfm made more vacuum than a 750 cfm. we took an engine that was making between 10 and 11 lbs of vacuum with a 750 and solid lifters and did nothing but put in Rhodes lifters and took the 750 off and put a 650 on and made 16.5 lbs. keep in mind though there are a lot of other variables, i.e. intake, comp ratio and so forth.

[let-r-eat]

If it doesn't have rhodes already get a set. If it does already get a MSD e curve distributor. The all in one electronic one with the dip switches for the advance curves.

You should be able to get there from there.