Cam affecting vaccum and timing

[pro_am]

okay my timing mark on my balancer kills the engine when we line it up there, but if we advance it(at least i think turning it that way advances it) then it runs great and idle's where it should. (btw my uncle and cousin built this engine as a christmas present, i have no idea whats in it) i also have very little vaccum, not even quite enough to power my brake booster. And idea if the cam could cause that, i have read that it does, but don't knwo for sure, and how about the timing thing, thanks again for the help!
Jake

[CreepingDeath94]

Well, I can tell you for sure that the cam would affect vacuum if it was radical enough...and it sounds pretty radical. Set your timing so it runs right. If advancing it smooths it out, good. If you have low/no vacuum, they make vacuum reservoirs and various other items for wild cam engines to run brake boosters and what not. Luos and Formula Im sure have a better idea what to tell you on the cam...

[pro_am]

Thanks a lot for the response i appreciate it. I'll look for a vaccum reservoir. Appreciate the help!
Jake

[Mr. Luos]

I have to idle at 1000 RPM's to make sure I have vacuum.
This is due to the cam. A cam can very easily effect vacuum.

[CreepingDeath94]

I know the theory behind why...but just barely. Basically, the more duration a cam has (that is the longer the valves are held open), the lower the vacuum. The reason being that if the valve is open longer, the vacuum created by the piston pulling away is reduced.

[Fuzzy_C]

timing marks don't mean much if you have a good, powerful engine, i power time all my vehicles, just pop it in gear, hold the brake, and let it rip, you pretty much need 2 people, one to be in the car, and one to be doing the adjustments, you notice some major difference behind the wheel between timing adjustments, i went through like half a set of rear tires before we got the timing perfect, but oh well, they have a tread life warranty, and my car seems like it has twice the get up and go that it had.

[pro_am]

how do i know if i need a different torque converter than stock? Thanks for the reply's guys, I really appreciate it!
Jake