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Cam recommendation needed

FM Former Member
I just grabbed up a nice stroker crank, and rods and a set of barely used 92 pistons and barrels. I've already got a clearanced case that's been opened up for 92's, plus a set of stroker pistons in case I need them. I won't know until I measure the rods, but I've also got a nice set of SCAT rods just in case.

The heads will be a spare set of CB mag 44's, heavy duty springs, and stock length moly push rods. I have some 1:25 rockers if I need them as well.

Carbs will be Kadron's or a single side draft (DCOE?) Weber.

I want an engine that will pull like a freight train. No need for blazing off the line performance, I'd much rather a strong pull from 3500 to 7000 for the highway. You know how a stock cam has that great third gear, through the twistys kind of pull and then the sweet fourth gear shift around 55 MPH or so? I'd like THAT kind of thing, but farther up in the rev range. The crank will provide the torque, I want to move the power band to the other side of the tach.

Does anyone have a recommendation on which cam would be best for that?

I'm a little lost on what to choose. I've already got a VZ 115, a VZ 125, a 100, an FK8, and a Web cam that's close to a 120, but if another cam is the way to go, I'll buy that one and use it instead.

Any help? Thanks ! !

TC
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FM Former Member
I just grabbed up a nice stroker crank, and rods and a set of barely used 92 pistons and barrels. I've already got a clearanced case that's been opened up for 92's, plus a set of stroker pistons in case I need them. I won't know until I measure the rods, but I've also got a nice set of SCAT rods just in case.

The heads will be a spare set of CB mag 44's, heavy duty springs, and stock length moly push rods. I have some 1:25 rockers if I need them as well.

Carbs will be Kadron's or a single side draft (DCOE?) Weber.

I want an engine that will pull like a freight train. No need for blazing off the line performance, I'd much rather a strong pull from 3500 to 7000 for the highway. You know how a stock cam has that great third gear, through the twistys kind of pull and then the sweet fourth gear shift around 55 MPH or so? I'd like THAT kind of thing, but farther up in the rev range. The crank will provide the torque, I want to move the power band to the other side of the tach.

Does anyone have a recommendation on which cam would be best for that?

I'm a little lost on what to choose. I've already got a VZ 115, a VZ 125, a 100, an FK8, and a Web cam that's close to a 120, but if another cam is the way to go, I'll buy that one and use it instead.

Any help? Thanks ! !

TC
FM Former Member
Hi TC! Would this work? (as per Gene Berg's website): GB 302A: "Like GB 302 with very fast ramps and much more lift. For wide high RPM range with limited carburetion. When used with larger Webers it runs well in low end also. Requires at least GB 269 triple springs and possibly GB 272A Chevy springs. 309 duration, 0.445" lift at cam." That's the equivalent of an Engle VZ-35.

For your info; this is what it says about GB 302: "For the more radical engine. The larger the displacement and the more head work the better the performance and the smoother it runs. Commonly used in hot street cars with 1900ccc or larger motors with dual, dual throat carbs and head work. Requires GB 273A dual springs shimmed to 0.070" from coil bind and if used for higher RPM purposes use GB 269 triple springs. 2500-6500 RPM range with dual, dual throat carbs and proper head work. 308 duration, 0.405" lift at cam." The equivalent of an Engle W-130.

The GB 302A sounds close to what you're looking for.
FM Former Member
First off, what's this engine for?

It sounds like you are putting a down-and-dirty race type motor together. Assuming that, and that you really want it to make some power, go with an 86c. The 86b is awesome, but does leave something on the table. Use the 1.25, or 1.4s if you can get them.

One comment, the 92s are about the worst cylinder size as far as cooling. External cooler with fan, and make sure it doesn't run lean and it will do better.
Ron
FM Former Member
Torque is a product of HP and RPM. A 100 or 110 just won't give you the HP, and therefore, the torque. For HP and torque a bigger cam is always better. But sometimes there are some compromises in other areas, like idling. That's why we all usually go for something like an 86b instead of an 86c. However, the 'c' is still a reasonable cam.

Getting a flat torque curve, which is what gives you torque down low, is mostly the result of heads that flow well at lower vacuum (lower rpm). For racing, and advertising dyno numbers, all you care about is peak HP. For that you want heads that flow best at maximum vacuum. For all around driving you want heads that flow well at all amounts of vacuum. Darren is a wealth of information, and a good porter of heads.

I'm still wondering what you are going to use the engine for...
Ron
FM Former Member
My jake recommended Webcam 122/125 split-duration cam within my 2110-cc makes power throughout the entire HP curve and the torque curve is awesome, power is everywhere! Use it with a pair of 44 Weber IDF's or 40 Dellorto DRLA's. Give it about 9.25 compression ratio and about 26 to 28 degrees on your timing and you'll have a smile from ear-to-ear like me! You'll have to dedicate some time to properly set up the rocker geometry. The intakes and exhaust pushrods lengths are different due to the different lifts and durations between the intake and exhaust lobes. GOOD LUCK!
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