Cam Question

[Clintond]

I need help in selecting a cam. It is for a 1975 C-10 with: performer rpm manifold, 750 holley, 190 Pro Comp heads .600 lift 64 cc, 1 5/8 headers, 2400-2700 stall 350 th, 3.73 gears. It has now a CR of 8.5 with factory 76 cc heads. What head gasket will give me at 9.5 cr with the smaller chamber? I would like close 400 hp. I am doing porting work on the heads and intake. The XE 274 and Voodoo 276 have caught my eye.

[Scott Liggett]

Re: Cam Question

I had the XE274 in my Impala for ten years. I liked it alot. Still produced enough vacuum for the brakes. You got the right gears and stall convertor already.

To get compression ratio just enter the numbers in any number of calculators on the net. You need bore, stroke, piston's deck height (above or below deck), and chamber size.

64 cc, 11 cc dished pistons, bore 4.030, stroke 3.48, .025 below deck (about average), .041 head gasket volume, head gasket bore 4.065 comes out to be 9.2:1.

These are about average for a dish pistoned 350 from that era. If you have different stuff, write it up.

[HEMI]

Re: Cam Question

Why not just contact the cam grinder of your choice?

[Bamfster]

Re: Cam Question

Talk to Reed Cams, they custom grind and have it to your door in less than a week.....

[DanStokes]

Re: Cam Question

Reed's good. So is Delta - and cheap. They are only so-so about making recommendations but Comp and others have a calculator on their website and that will get you really close. I get the specs from Comp's site and order from Delta - works pretty good.

On combustion chamber volume - just buy a 5x5 (or so) piece of plexiglass and drill a small hole in the center. Go to a decent pharmacy and buy a BIG graduated syringe (mine's 80cc). Tint some H2O with food dye. Seal the plexi to a combustion chamber with a SMALL amount of petroleum jelly and measure your volume. Measure the volume between the top of the piston at TDC and the block deck. If you have a used head gasket you can even measure that - put a piece of glass under it and your plexi on top. Then do the math.

Dan

[TheSilverBuick]

Re: Cam Question

Dan's rolling in dough :P After purchasing the $3 syringe from the grocery store my buget was expended. I refilled the syringe I think 4 times so it's probably a 25cc, and I set it to 20cc's each time. I used an old CD case cover in place of the plexy glass, a little bit of soap(dawn) in the water to break the surface tension (be careful of bubbles) and just watched for the last of the air bubbles to disappear under the case, go slow and steady. From a measuring point of view your accuracy is going to be within a cc, and a drop from a syringe is less than a cc, you can get a good estimate of which drop does the spill over or fills the cylinder. When rounded to the nearest whole number mine matched up to what cc the head was specified at, I measured two different heads ('70&'72) with two different volumes and they both checked out at spec.

[HEMI]

Re: Cam Question

[fahrenschnell]

Re: Cam Question

Comp 292....IMO

Seth

[mlcraven]

Re: Cam Question

I need help in selecting a cam. It is for a 1975 C-10 with: performer rpm manifold, 750 holley, 190 Pro Comp heads .600 lift 64 cc, 1 5/8 headers, 2400-2700 stall 350 th, 3.73 gears. It has now a CR of 8.5 with factory 76 cc heads. What head gasket will give me at 9.5 cr with the smaller chamber? I would like close 400 hp. I am doing porting work on the heads and intake. The XE 274 and Voodoo 276 have caught my eye.

You won't be at all disappointed in the Lunati Voodoo line, although I'd rec stepping down a notch to the 262 if it's mostly for street use. On a 10:1 383 otherwise identical to your set up it yields 445 lb-ft and 405 hp on the engine dyno. As for real world? 12.8 secs/108 mph in the quarter on street tires (3500 lb car incl driver and gas).

[Clintond]

Re: Cam Question

Thanks for all the replies. This is the hardest part to buy.

[DanStokes]

Re: Cam Question

Oh, it's EASY to buy. It's knowing WHAT to buy that's hard! At least for me.

Dan

[revolutionary]

Re: Cam Question

I'd run a 288/306 @ .050 with .500 valve lift, 126 lobe separation installed at 91

hydraulic flat tappet

[SpiderGearsMan]

Re: Cam Question

Mike Jones
Jones Cam Designs
Denver, NC
camwave
(704)489-2449
email [email protected]


UD Harold Brookshire
662-562-4933
email [email protected]

[yellomalibu]

Re: Cam Question

He needs a 3/4 race cam.




... what? Someone had to go there ;D

[TC]

Re: Cam Question

Comp 292....IMO

Seth

To big for the amount of compression he'll have.

Personally the Comp XE 274 would be a good choice. Or better yet think GM Hot Cam, they make 425hp with vortec heads and that cam in a 350.