I am getting closer to pulling the trigger on a 383 stoker engine. However if I put a "hot" cam inn it it seems that power brakes and pop up headlights will suffer - the engine builder wrote " That is an issue. You can't change the physics of how a cam works, and if you want *****-out power, you ARE going to run into this problem. If it wasn't a problem, there would be no use for things like extra vacuum cannisters, hydroboost brakes, electric vacuum pumps, manual brakes and so on. I can split the difference and give you a cam profile that will kind of work, but NO ONE on the planet can pull a magic wand out of their butt and make a killer cam produce enough vacuum to run power brakes, or things like headlights and stuff. If you want ***** out power, you will have to bite the bullet and go with a small electric vacuum pump or something, otherwise you'll have to sacrafice power and go with a smaller cam.
Comments ? Suggestions? Thanks,

Alex

 

What cam are you considering? Your builder is correct that certain, agressive cam profiles will not have the vacuum for certain things. However it is very possible to build a nice motor with a cam that does have good vacuum characteristics.

What will you use the car for? For a street driven car I think there are a lot of options that will work well. If you want a combo of good manners and ***** out power you should look into nitrous oxide.

 

Joel, I am considering http://www.badasscars.com/engineprices/chevsb.html

the450HP - 530HP 383 crate motor eater from Hell: With all of the big companies offering what they call "powerful and reliable" pump gas crate motors, including GM and even the new Edelbrock engines, we felt it was time to blow them all away with power and quality for about the same price, here's what you get. A fully prepped and machined 4 bolt main 350 block fitted with ARP main bolts and special hardened Federal Mogul race bearings, a new 4340 forged steel crank, 6" 4340 forged steel H-beam rods with ARP bolts, forged Super Lite JE pistons and iron ductile rings, a custom solid roller cam and light weight roller lifters, a double roller timing assembly, a ported Edelbrock Victor Jr. intake manifold, Victor Jr. aluminum heads, aluminum roller rockers, chrome moly push rods, ARP head studs, High volume oil pump with hardened steel shaft, new nodular iron harmonic balancer, new flex plate, new Holley 750 carb and a new high performance HEI ignition. This engine comes complete with chrome timing cover and oil pan and is assembled with Fel-Pro gaskets, stainless steel bolts and is fully balanced. It will run on pump gas, it's ULTRA strong and will flat-out make more horsepower and torque than any of the small block "crate" motors offered out there, by a long shot! $8,495 .

Wanted to go for a 434 but the price difference is almost 5 grand!

Any well buily alternatives? Alex

 

Speaking of vacuum,
I now have a 264 mega cam from Isky, The vacuum assist takes about twice the time it used to to operate.

it just takes a little more time to open the lights and if I have to brake at low rpm's I just shift it into neutral and pop the revs a little, after you let off the gas, your vacuum is sufficient to power the brakes firmly.

Then again, mines a cruiser and occasional drag racer, I'm not left foot braking through a road course.

 

I bought a badass 383 from Aaron about 4 years ago. He installed a very nice roller hydraulic for me. the lights work fine and the power brakes are mostly power. lol. Aaron can build you the engine you want. I have pictures of my green 73 on his website. He builds a sweeeeeeeet engine. I am using the comp cams lifters and a crane cam. I have about 525-540 at the crank naturally asp.

 

Pardon me for being confused, but what does vacuum have to do with opening headlight doors in a midyear?

Am I the only one that has electric motors for that function?

 

Gilbert Chevrolet has a ZZ500 383 crate engine (500hp)for less than yours. It is all brand new (not rebuilt). That's not blowing me out of the water.

 

EXACTLY WHAT I WAS THINKING

 

I have a big roller cam and my vacuum is fine. The roller cam is a very good way to go. Its no magic wand but its close

 

Maybe they're trying to have the engine make enough vacuum to "suck" the headlights out of the housings on a midyear.....

 

I have a low vacuum producing Comp cam in my 57. It only produces 11 1/2" of vacuum .... just totally screws my dual quads in the idle mode!

 

While it`s true with a wild cam there is less vacuum to operate C3 lights and wipers they can be used for a street applications. The lights just close slower. My L88 powered 1968 has all the vacuum thats necessary. And mid year C2`s will not be affected as they are motor driven.

 

John, I had the same problem with my 61. I am assuming you have the dual WCFBs. You probably need a weaker spring under the vacuum piston that pulls down the metering rods at idle. You can pull the small cover on the front of the WCFBs and see if the metering rods are in fact puling down into the jets.

If not you are NOT on the idle circuits and need to replace with a weaker spring.

Joe