glen242

I am starting to assemble parts for my new 383. Am going to use the TF 23* heads, Edel Performer RPM intake, and headers from my original motor. Bottom end will be new Scat crank and rods. Pistons will be Speed Pro Hyper, giving me about a 10.5 C.R.

My cam choices are CC Magnum 270, 280, or 286.

I put about 1,000 miles a year on her and will not take it to a strip until they build one within 20 miles of my house.

Anyone have any suggestions, and/or experience with these grinds?

Brettmc

This:
http://www.powerandperformancenews.c...&Store_Code=CC

Brett

glen242

ttt

comp

need to match cam to your head flow

mountainmotor

Glen ,

It is important to take rear gear and transmission into the mix .

I'd be looking at the Isky 270 Mega cam probably . Just depends on lack of info provided .

To give you an idea about the cam you posted , in most sub 400 inch engines the Comp 280 will not get you to the end of the 1/4 mile any quicker than the HE 268 with good heads if an automatic with 3.08 gears are used but I do think the HE 268 is too small for this engine of yours just by a hair

glen242

3.36 rear - ST10 wide ratio 4 speed

Just ran a bunch of DD numbers using various cams. I wanted to stay with a single profile cam, like the CC Magnum series, but comparing the numbers it looks like the XE268 is superior to the CC Magnum 270 in that it makes more power over 4000 rpm and the same power under 4000 rpm.

evelkevin

Looking at a cam catalog is very confusing if you don't take certain aspects into consideration. Comp cams catalog covers 265-400 ci engines and you can certainly believe that the same cam can be too big for one and not enough for the other. With your 383, the heads, and the CR I would rather err on the side of too big instead of too small. Plug the XE274 and the XE284 into your DD and see which one you are more comfortable with. BTW single profile cams are dinosaurs and stroker motors like bigger cams.

Fevre

I ran a XE284 in a 383 with 10/1 comp, TFS heads and rams horn manifolds into 2.25" exh, it did not lack low end with a 4 speed and 3.70 gear. The XE274 might be better for your 3.36 rear end.

Forgot: I was running Crane fast bleed lifters which are supposed to decrease lift and duration at idle, I got a bad short block so the eng was not together very long, did not really beat on it but it def had some get up and go.

C3 Stroker

I had a similar set-up as yours (383 with TF 23* heads). I used a CC Magnum hydraulic roller 286HR. This cam is similar in duration to the Magnum 280 but with higher lift. Very good results, good driveability, good vacuum. Good but lopey idle @ 800 rpm. Should use 2400 stall converter in auto trans. Got better performance AND gas mileage with 3:55 gears than sluggish 3:08's. Dyno results- 360 hp & 380 ft-lbs torque at rear wheels.

Glensgages

glen242:
I run the 292H CC grind, in a 355" 10.3:1 CR SB w/ DART II (iron) heads, Victor Jr, etc., in my '79 Z28.
The rest of the drive-train is a 2.75:1 low-gear THM400, 8" converter, 4.10 gears, and slicks, and it runs 12-eighties at 105+.
On the street, w/ a 10" converter and 26" x 8" street tires, it ran 13.30s, and it wasn't that bad a ride as-far-as streetability.

I doubt anybody'll be building a strip near you anytime soon:
Pittsburgh Raceway Park has done a ton of improvements the last 3 years under new ownership, and is really doing well.....

Come out and play!!!

mountainmotor

I beg to differ

But I don't have the time for it so you win by default

Fevre

Seems I have read that if the exh ports flow 80% (or greater) of the intake ports than a single pattern cam is better.

tsw71

Dual pattern cams are used to compensate for poor exhaust port flow. I'm running a single pattern cam (282S) with the TFS heads on a 355. It's a very good match.

With a 383, I would not go with anything smaller than the 280.

evelkevin

OOH, I knew this statement would start controversy. With all due respect, camshaft selection and head design have greatly improved naturally due to the advent of computer aided design and simulation. Most single pattern cam designs such as the comp cams magnum series have been in their catalog since the 70's. The vast, and I mean vast, majority of all newer cam designs by GM, Crane, Comp Cams and the like are split pattern simply because they work better.

Back to the original post: If there is any way to fit it in your budget, a hydraulic roller set up it truly the way to go. The ramp angles of the lobes will allow the valves to come off their seats much faster which creates significantly greater power gains with the same sort of lift and duration numbers. Flat tappet cams, albeit inexpensive, are also becoming a thing of the past.

Ironcross

Why do people build engines for performance with a bunch of trick high dollar aftermarket parts and then limit the potential HP by 1000+ RPM`s by using a hyrdaulic cam that flattens out close to 5500+. Seems backwards to me. If you can`t spin the engine you may as well keep all those fancy parts in there boxs It may be good for bolstering in cruise parking lots but it sure wont win any races.

SpyderD

I think the limiting factor of RPM use is not really hydralic vs. roller, etc but the valve train - and by that I mean light weight but stronger rocker arms, push rods, valves, springs, even down to the pistons. But this is moot anyways - the key to building up a street car is to build up the torque in the streetable 3,000-4,000 RPM range, and people spend (or should spend) their dollars on achieving that goal. Why wind up a car to 7,000 RPM when you get peak torque/horsepower in a much lower range?
Dual pattern cam's are not "the wonder cam". But they do work well on stock heads that are limited by restrictions in the exhaust valves, port, manifold, etc. They have little benifit if you have a highly modified head. There are exceptions - Pro-stock cars use dual pattern cams but they carefully match them to the heads.
Actually, TPI chevy engines don't work well with dual pattern cams.

Larry3x2

Glen: My son had this engine built and wound up having to sell his '75.
I recognize you asked a cam question but perhaps you'd be interested in comparing your parts selection.

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http://www.csc.villanova.edu/~wthau/383.html

Larry

glen242

Interesting. Was it ever in a car? I wonder how streetable the 292 cam would be with a 3.36 rear and a 4 speed. Nice numbers regardless.

Larry3x2

Glen: Engine is totally brand new with 20 minutes on the Dyno. Should run well with 3.36 and a wide ratio box as it puts out 472 lb-ft @3500. I'm not sure what you plan to use it for. Drag racing would be best with at least 3.70 rear gears. Engine was built by a circle track and drag race builder. My sons contact info is on the engine link.

Larry