StrayDog

Age old question on Cam change...my 427 is .30 over, 3.08 rear gears & wide ratio 4 speed.... a street driver ... 3080 with no driver & 1/2 tank of gas. has 9.5 compresion due to Endlebrock Alum heads....want a high tourqe cam , will be keeping 308 gears, & a 6000 RPM redline , as I go to drags once a year on Oldies Day at NE dragway....last year best 13.7 @ 102 MPH :yesnod: 2.6 60 foot times , had poor traction in first gear ....anyways most driving is actually in 1300 to 4500 RPM ....as the 308 gears will not be changed ..Tourque is my objective , but I still want to rev to 6000 rpm....i want the best of todays cam tech....I think the cam in my engine now is the L36 , 390 hp.....my block is a 425 HP , with TRW 2300 F , .15 domed pistons Pistons , the block has been milled ......have to limit valve lift to .500 , need a cam to be compatible with 9.5 compression ratio ...was thinking Comp cams XE262, or 268 high energy ...Crane has a 272 that looks ok, they have been running a comparison add to the XE 262 & they , Crane , NOTE 18 more HP & 15 more FT lbs of tourque , through entire range up to 6000 RPM...so this only :eek: confuses me ...it boils down to this looking for the best in modern cam technowledgy , with 450 ft LBS of tourque & a HP peak of 5500 rpm & A 6000 REDLINE :crazy:

Katz

Most of the #s advertised as HP gain with cams are bunk; it takes a lot of components other than a cam to work together to make a motor which runs right. I have a Comp Cams 280H in the 283ci block in my '58 which is a bit more of a mild build-up than your big-block. The cam is barely streetable and it will load-up from time to time. But the car also hauls but it doesn't have the low-end torque (more due to a lack of displacement than cam.)

Comp Cams makes a decent cam (at least from what I've seen in my 283.) Have you tried calling their help-line for suggestions? Also, with the cam are you going to get matching lifters and springs? Since you're going driver you're planning on sticking with a hydraulic lifter setup, right?

kahuner

StrayDog;

Get in touch with 427HotRod. He selected my cam and it was exactly what i wanted......torque. His recommendation was entirely different than what I got in the way of advice from Comp Cams. Comp Cams would've had me in the 260* duration at .050" and 427HotRod selected a cam that was 236*I/244*E with approx. .544" lift.

My range is from 1200~5200. If I dump the clutch at 2K, I go sideways w/ a 3.55 rear gear!

StrayDog

Kauhner....what specfically is the cam you are useing ? Theb Dog

SWCDuke

For the torque bandwidth you're looking for, I don't think you can beat the OEM L-36 cam and the OEM or equivalent valvetrain components. Most aftermarket cams have too much overlap IMO. Overlap will improve top end power with properly designed headers, but with OEM manifolds is just kills low end torque and doesn't help the top end that much.

Duke

64BB

DUKE, I KNOW THIS IS BASIC, BUT WHAT DOES OEM STAND FOR??

clearrun

Original Equipment Manufacturer, i.e. I believe he means the General. :D

SWCDuke

Correct. I don't think you can beat the original cam that GM installed in the L-36 for the best torque bandwidth in the range you specified.

Duke

dhendo

The stock L36 cam is exactly the type you want based on your post.

427Hotrod

I've already given you my rough ideas in the I/M, and we can really narrow it down to a specific grind if you're interested.

I agree with all these folks that GM does an excellent job designing cams. There are many killer small block ones, the LT-1 and the several Z-28 variations to be sure!

Now I don't know if I'm a giant fan of the L-36 other than as a nice low rpm super smooth torque cam. As even as a mild performance cam I feel it leaves a lot to be desired. With the combo you have, which is much stronger than stock, I believe we have to compliment the upgrades.

I absolutely love the L-72 cam on the street especially for ovalport 396's and 427's. It has just enough lift to get the heads flowing. I have run so many deep 11 sec passes with it in several different motors it's ridiculous. Even stock oval ports respond very nicely to lift in the mid to high .500 range. The aluminum ones you have really need some more lift to work out. Of course it's a solid cam and does not fit what you want. There is also a Hyd. version of this cam that Gm uses in the newer LS-6's I believe. I saw a dyno test where they compared it back to back with the solid one and they were almost identical.

You're right to be careful with too much lift. The depth of the L2300 piston notches won't be an issue up to almost .600 lift usually, but the edges of the pockets can get real close to 2.19 valves. I mean REAL close and sometimes needs massaging. Mid .500's lift will be fine.

Remember, lift isn't usually the problem with P/V clearance issues. Usually duration and valve timing cause the problems. You just have to pick the right combo to keep everything apart.


Jim