Thread: cam selection time...opinions,anyone?

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first off,I'll start with the engine..
396 .30 over,112cc oval ports [ port and polish],speed pro .335[38.3cc] dome pistons,750 holly,vintage Holley intake from '66 427 stingray,10.5:1 compression.
So...obviously I'm looking for a cam to enable me to run the 10.5 on the street on 93 octane by bleeding off some cylinder pressure,so i call up Jegs tech help line,just to see what they had to say.Well,what i got was "run 3:73 gears,3,000 RPM stall,and the comp cams Xtreme 284[240/246@.50] cam and you'll be right on".
Sure! sounds good,unless you're like me and just have to get that second opinion!So,i give Comp cams a gingle,give them the rundown on the car['81 camaro] engine setup,etc., and he says,"well...the 286 magnum[236/236] will be just right". how's about the 284 xtreme,i asked."well,you CAN use it,BUUUT...when it starts pinging and detonating,just Remember...I recomended the 286 magnum!"....and said i can't hold him accountable when it does.
Puzzled i was,and still remain.i thought these guys were>tech experts",yet I got 2 OTHER recomendations from 2 differrent companies .
needless to say,I'de be rerally interested in any and all recomendations you guys have to give!!
thanx a bunch!!!!!!!

Fill out the cam selection tech sheet completely for a couple different companies, see what their reccomendations are. I would think they know a bit more about cams then some phone bank dude at Jegs.

Plus the guy at Jegs is looking at what they have in stock and need to move!

is that the gear & convertor you plan to run in the camaro ? 3000 stall & 3.73s ?

In my opinion you should be fine with the larger cam if thats what you want. I run 256 270 duration at 50 with 11 to 1 compression in my small block on 93 and i dont have any detonation. I think your fine with the larger cam

yup,3000 stall and 3:73's.Thanks for the unput,guys!

In theroy, the Xtreme energy cam would give you less compression and therefore less chance of detonation. The more duration you have, the less compression you have. That is why with bigger cams, you need more compression, because your valves are open for a longer period of the cycle, it does not produce as much compression as do shorter duration cams.

My guess is that they Comp Cam tech was caught off guard or else you misunderstood.

Good call,Typhoon.I was even considering the 292 Magnum grind whick would give out 244/244 duration and more than enough overlap for what i need.but perhaps the Xtreme would be sufficient?

Burn,
the larger the displacment the smaller the effect on the idle of the motor the cam has. If you have 400 cubes and installed a cam with 250 degrees at .050, the motor would idle just fine, however if you install that same cam into a 305, it would be absolutely horrible.

I have more duration @ .050 than most guys have advertised duration. I have some 266.272 degrees of duration at .050, I use my stock brakes, a 3500 stall converter, but I have 12:1 compression and 406 cubes.

The larger the cubes the bigger of a vacuum pump your engine is, therefore it can handle a larger cam.

If I was to suggest a cam for your motor, I would say go with the Xtreme hydralic roller11-444-8 if you have the money or go with Xtreme hydralic11-254-4 if money is limited.

Obviously the roller will make more power and if you don’t mind adjusting the lash once a year, go with a solid roller cam for they make the most power of all.

Cool! I think I'll take a look at those grinds

Cool! I think I'll take a look at those grinds