Hello, I have a jq 69 396 265 hp. It has a performor 2 edelbrock intake and 4 barrol carb. I also have headers installed on the engine. I had the heads completly redone $$$$, before I new they were the open chamber truck type. Looks like I am at 9.1 comp. What I would like to know is a cam that I can use with this setup to get me Max. HP. PLease give me a part# or specs if you would be so kind. Thanks Steve

Im not an expert but id be surprised if your comp ratio is at 9-1, what cc are your heads, and when you had them redone how big of a valves did you put in? I was gonna use a set of 781's on my 396 but they wouldnt match my cam choice, my comp ratio would be to low. I had even put in some pretty big domed pistons. So now im stuck with a set of heads i wont use. im sure someone with more knowldege can give you a cam selection. id stay away from anything with much overlap, that would drop your comp even more

Yea 9.1 is what this motor is stock and thats what I got, has the large oval truck heads 148's. I am not worried about the 9.1 comp as this is not a drag car and the engine runs pretty strong. What I am looking for and you are correct, a cam to get the "most" hp out of this set-up, only a cam change, nothing else, to put this motor at Max hp. Thanks Steve

Heck, at 9 to 1 CR., I bet any of the from a 266 up to a 272 advertised duration cam would work great to boost your power..

And a set of cheap, 1.75" four tube, long headers and free flowing exhauast will definately help too!!

The, what is it?, 192 or 4(??) at .050" duration with only like .398" lift cam plus cast-iron manifolds don't help the little bugger at all even if it is a BB, imho..

Sounds like you have the intake system under control, too..

pdq67

Crane H266-10
http://www.cranecams.com/?show=browseParts&lvl=2&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=CHEVROLET&Year=1970&Engine_Size=396-454%20C.I.&partNumber=103042&partType=camshaft

or thereabouts.

Thanks thats just what I was looking for, looks like the next one up looks good for my LC engine. Thanks again , Steve

Yes..

That's the 266 cam I was thinking of..

pdq67

before I new they were the open chamber truck type. These are NOT the peanut port truck type... these are the large oval port style. Other than the large chambers, I think they are actually decent 396 heads.

My '74/'75 P/U, 454 core motor had a good set of -781's on it..

They did have rotators tho..

pdq67

Look at the Isky 262 Supercam. Very similar to the Crane 266.

Grind No./Type
262-SUPERCAM HYDRAULIC Low/Mid-Range performance cam. 9.5
1 compr. 3.08-3.70 axle ratio. Passenger cars & trucks. Up to 625 CFM Carb. RPM-Range
2000-5500 Valve Lift - INT
.488 EXT
.488 Valve Lash Hot - INT
.000 EXT
.000 ADV Duration - INT
262° EXT
262° .050 Duration - INT
208° EXT
208° Lobe Center
108°


http://www.iskycams.com/engine_template.php?catid=127&engine_id=20

thanks for the research, great options out there, now the hard part to choose. Great work, I appreate all the effort. Thanks steve

BTW... we have a 265/396 in my Dad's '70 'vert. It is a stock rebuild (including 265hp heads) with the following parts added:

750 CFM Edelbrock carb
Performer 2-O manifold
Blue Racer cam (204/214 @ 0.050, 0.476/.0.501, 112 LS)
Stock Chevelle exhaust manifolds

He is using a TH350 w/ 3.08 gears. Runs pretty good for a mild combo. I think one of the cams recommended here would be even better than what we used... had I known more at the time, I'd have picked something like the 266 Crane cam. I think 5-6 deg more intake duration would be a good thing.

Still, the cam we have works very well... it signs off at 5k rpm though. Plenty of midrange to pull that heavy convertible w/ no gear and low compression. I think one of the cams above would make more power.