got my engine back from BUTLER PERF.,and got it all back together,runs great but with the cam they installed,I have a little problem with the vacume at idle,the brakes are a little hard to hold.other then that,they stop on a dime.I have a holly street dominator and I have the power brake hose plugged into the rear of the carb.any other place that has a better source of vacume or any other Ideas.? :rolleyes:

if you can find a bigger hole in the manifold you could try it, but i doubt it would help. Test the check valve and line(s) before anything, but if the cam is too big, and only slightly so, for the power assist to work right, I think you can get a reserve canister which will hold a little extra 'shot' for you. there are also vacuum pumps sold for this problem in extreme situations.

check jegs and summit.

edit:
check summit part
CRN-99590-1
by Crane Cams.
you could probably make one, but this one sells about $50.

That would be the best way to go with out having to re-do much. A friend up here with a built 455, E-Heads, large cam etc installed a fluid assist system that runs off the Power Steering Pump. Looks awesome, and he said it works great!

But then you are having to red do some of the lines, add some hoses etc... more work and more expence etc.

Check out a vacuum can first?

Brett - 67 Drop Top 455!

You could also install Roads lifters, they help tame a big cam at low rpm's and you get more vacume for brakes. (No change at high RPM's)

Jim G.