PDA

View Full Version : Cam choices



sunkistcamaro
03-11-2005, 09:35 AM
Hi guys,
What cam should I put in my engine? Im definitely not an engine builder… and don’t know what to choose.

These are my engine spec’s.
- 350 block, .030 over, zero decked about 10 to 1 compression
- Keith Black pistons with 4 valve relief’s.
- Stock cast crank
- Edelbrock Performer RPM heads with 70cc chamber volume
- Victor Jr intake
- Stock Rod length
- BG 750 CFM carb

Any help would be appreciated
Thanks

WELTERRACER
03-11-2005, 09:46 AM
Lucky for you ive tried 6 different cams and 3 different intakes on my SBC that is pretty close to what you have..

Do yourself a favor and buy the matching Performer RPM cam to match your heads.. You should end up at 425HP.. It will pull hard from 2500-6500rpms.. and will work great with 3.73 or 4.10 gears.

I also tried a slightly smaller SUMMIT cam #1105.. stock type idle and pulled hard to about 6200rpms.. but i could tell i lost about 30+hp over the RPM cam... The summit cam was great power to Price and gave awsome vacume for brakes.. I am also using 1.65 roller rockers..

WELTERRACER
03-11-2005, 09:48 AM
The Performer RPM or RPM airgap would be a better intake than the JR... I TRIED ALL THREE..

WIth the JR. You loose alot of lowe end torqe and drivability..

sunkistcamaro
03-11-2005, 10:17 AM
Thanks,
I do have 3.73 gears but 1.5 roller rockers.
I guess it would only make since to use a matching set up.

Lowend
03-11-2005, 07:08 PM
I really dislike the Edelbrock RPM cam... it just does not seem to put out the numbers when I have used it in the past.
We should first ask, what kind of RPM range do you want to operate in?
There is a pretty wide girth in going from peak power at 6000 and 7000RPM.

I fear to say that your engine is probably not 10-1 compression. With a flattop piston and a 70cc chamber you are probably around 9.1

In general I would like to see a cam with a very wide lobe seperation on this engine, it won't sound as cool, but the powerband will be much broader.
My general suggestion
220/230@050
112 Lobe Seperation (4 deg advanced)
Don't worry about the lift.

Isky makes an off the shelf cam with almost these exact specs I would suggest

sunkistcamaro
03-12-2005, 03:53 AM
The operating range is going to vary just because I drive it to work on the hi-way and lots of back roads. Im pulling out the TH350 and installing a 700R4 in a few weeks so I really don’t know how it’s going to change my RPM range. What do you guys think about roller cams?

ProdigyCustoms
03-12-2005, 04:10 AM
I agree with lowend that your compression is lower then you think. You do not need a hydraulic roller, and surely no solid roller.

WELTERRACER
03-12-2005, 05:26 AM
Ok .. than use a cam similar to the SUMMET 1105#... It has .465/.488 lift and 224/234 duration and a 114 centerline... it idles smooth and has great vacume.. and your motor should make 375-380hp...

Is your engine set a 0 deck hight?

sunkistcamaro
03-12-2005, 05:38 AM
Yah, I know it's zero decked.
The guy at the machine shop that did it thought that it was a good idea.
He just told me he would stop by and check the valve to piston clearances before I assembled it.

WELTERRACER
03-12-2005, 06:53 AM
You are probobly close to around 9.5 compression which isnt too bad..

Your best bet would be to call COMP CAMS.. they would be able to give you the best cam for your application.. Im sure duration will be in the 224-234 range and lift around .480-.500 lift..

sunkistcamaro
03-12-2005, 08:08 AM
WELTERRACER thats a great idea!

Thanks everyone for your input :worship: