Thread: too "little" cam?

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Ok, just curios what some of the gurus think out there. Just picked up a 65 Chevelle SS from an estate. Engine was recently rebuilt (not original engine), and to me seems a bit under cammed. The engine runs strong, is reliable etc.. so no issues there.

here are the details, as best i know from the build sheet, and what i see-
*350 4 bolt bored .060
*steel crank/"pink" rods (wtf??)
*KB flat top pistons/ valve relief cuts (build sheet indicates 10.25-1??)
*Angle plug heads/2.02/1.60 valves (dont know combustions size.. sorry)
*GM HEI ignition
*GM "low rise" alum. manifold/Q-jet
*heaers (look like Hedman, not sure).

here's the cam specs, and where in lies the question (too little cam or just right)?

Duration Duration Lift Lift
(adv) (.050) (valve) (lobe)

270° 204 .420 .280
280° 214 .442 .295

112° Sep
108° Int C/L

What im thinking of chaning/adding is The Lunati 268 "voodoo" cam,
GM Z28 factory alum. intake
Holley 650 double pumper.

Yeah, could be a little limp. The Voodoo cam will definately open 'er up a bit. Could possibly go slightly larger than that since you have good compression and decent heads.

try the comp exstreme energy cam. bigger cam is not always the answer. you have to tune to how it will be driven. big valve heads kill port volocity.

The person who built your engine proberly knew what he was doing. In your words the engine is reliable and strong. The cam is either a Edelbrock performer or a simular copy of that cam. Summit sells a cam like that under their name,others are close as well. The combination that You are describing sounds good too,but im sure you will be making more trips to the gas station. If I were You ,I would drive it as is for a while to determine if that is what You really want to do . You might decide that you want to make other changes to the car that would benefit you more.
Sounds like you have a nice ride there, Enjoy!

thanks fellas, i must clarify i am only getting the compression ratio from what the build sheet indicated from the pistons and what the builder told me when i called them etc. The folks that built the lower didnt do the heads, so he was kinda estimating on the compression from the head info i gave him etc... In any event he said 10-1 to 10.25-1, so im hoping those are accurate estimates etc.

Im gonna drive it a bit more, get it painted, finish the interior (needs rear seat, headliner etc.)

After that i will determine if im gonna put a new cam/manifold/carb. or leave it stock.

Another option i was considering is haveing a 383 built for it, and using the 350 for a truck (seems like a good truck engine).

Thanks again fellas.

Lamey, "pink" rods were production Chevy rods that were magnafluxed to detect cracks and shot-peened for additional strength, then painted with a splash of pink paint to differentiate them from standard production rods. I remember that they were considered the hot tip "in the day".

http://www.chevyhiperformance.com/te...38/index1.html
http://www.chevy-camaro.com/parts/ch...es-connect.htm

I would urge you to do a compression test on your new motor to determine cylinder pressure. Be sure to wire the throttle blades open when performing this test. I suspect that the static c.r. is a little less than what the builder says because of being able to operate the motor on pump gas with that cam. 160-170 psi will be optimal for a pump gas motor and a change to a longer cam will not only lower the cylinder pressure due to a later intake closing point but will also move the operating range higher, obviously moving it in the wrong direction for a street motor.

My bottom line, I agree with riverhorse. Compression test it so that you know, then leave it alone and enjoy it.

thanks, will do the compression test. now a part 2 question-

If i leave the cam as is, would it be worth installing the Z28 type manifold and Holley 650 DP?? (currently has factory low rise late model alum. intake with q- jet).

thanks agian!

Lamey, the majority of power in a motor is in the cam and heads. You may pick up a little more from the manifold/carb change, but again, if it was my motor, I'd leave it alone. The Q-jet will flow more cfm than a 650 Holley and get better fuel mileage because of the tiny little primary venturis and huge secondaries for power. I know you're just itchin' to change this motor, but my best advice is to leave it alone and enjoy it.

ok, gonna leave it as is and enjoy... but will keep my eyes open for another SB Chevelle, Nova, Camaro to tinker with

I agree with Tech.

Drive it a while, see if it's got the cajones you want to feel when you mash the gas or not. If it doesn't, just plan to do a minor tear down, once the leaves start fallin from the trees, and make a little winter project out of a cam swap or whatever. Don't be like me and have 8 cars and no decent summer driver cause I need to "tinker" on the dang things.....and for some reason not just ONE....
I'd never leave any car the same for any length of time, that's what's Hot Rodding is all about. Change and Improve. Just make sure the changes happen in the 'off' season so you have someting to cruise in durring those better months.