While your idea for a short-duration camshaft to build torque might sound like a good idea, something closer to 210 to 215 degrees of duration at 0.050 for a 350ci engine is probably a better idea. This will allow the engine time to better fill the cylinders while still making decent top-end power. A good cylinder head will really help produce power at all engine speeds. My good friend, the late John Lingenfelter, said it best, “An engine with the best cam in the world but poor heads will be a slug. But a great set of heads will make good power even with a lame camshaft.” Truer words were never spoken. A good choice for a budget small-block Chevy would be the iron 1.94/1.50 valve size Vortec truck heads, since they flow well and are inexpensive. Or take a look at our small-block cylinder head comparison (“Eight Budget SBC Cylinder Head Shootout,” Sept. '09). The choice of camshaft should be based on the size of the engine. A larger small-block like a 383 or 406 could use a slightly longer-duration camshaft than a 283.
A 355ci small-block Chevy with a set of Vortec iron heads would be very torquey with a camshaft with around 210 degrees of duration at 0.050. You might be able to get away with increasing the lift with a set of 1.6:1 rocker arms, since all short-duration cams are valve lift–limited. This discussion is basically around a flat-tappet hydraulic camshaft. A hydraulic roller will produce more lift, but there are limitations to these short-duration cams that actually make the flat-tappet cam a wiser choice. If you want to know why, write an email to Ask Anything, and we'll take on that subject at a later date. This short-duration torque cam would work well with a 9.0 to 9.5:1 compression ratio, especially if the piston-to-head clearance is held as tight as possible. This improves quench and reduces the engine's sensitivity to detonation. A good exhaust system will help even a short cam, and long-tube headers will enhance low-speed torque as will a longer collector. Of course, a good dual-plane intake (we did that test, too, “Dual-Plane Intake Comparison,” Sept., '13) is the only choice for an intake manifold and a Quadrajet or a 600-cfm Holley carburetor will also help. Throttle response should be very crisp, with 400 lb-ft of torque, and this is more than enough power to make for an excellent street small-block that will be loads of fun to drive.
Here's a behind-the-scenes shot from one of the photo shoots we did during the Street Machine Nationals.
On a recent trip to our local junkyard, we were looking for old Chevy pickup steering wheels, and some random pulleys and brackets. We left empty-handed this time, but that's how it goes sometimes. Did you score something in the junkyard recently? Send pictures to CarCraft@CarCraft.com.
Do you love nostalgia drag racing? We're working on the Spring 2014 issue of Elapsed Times, our newsstand only publication dedicated to retro drag racing.
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