December 2011 Chevy High Performance Q&A

Kevin McClelland Oct 24, 2011 0 Comment(s)
View Full Gallery

Moving onto your camshaft selection, we’d stick with the Xtreme Energy 262 over the 268. The 268 only has several more degrees duration over the relatively short 262, but it will build more torque to move your pickup and give you better driveability. You will still achieve your power goals with the shorter camshaft. It’s been our experience with the Xtreme Energy camshafts that COMP has pushed the valvetrain dynamics to the limit with a 1.5 ratio rocker. Going to a 1.6 only excites the valvetrain in the higher rpm, where you would expect to see a power gain from the increased ratio. Stick with the 1.5 ratio and go roller if you wish. It’s not necessary with your camshaft selection. When you set up your engine, use the complete camshaft package from COMP, with its hydraulic lifters, springs, and retainers. This matched package will give you trouble-free performance. The factory Vortec springs will not control the valvetrain with the Xtreme Energy camshafts acceleration rates. We’ve run Teflon valve seals for years with no issues. There are lower priced Viton seals with a Teflon insert that we’ve seen the Teflon come out of the seal. This happens when builders don’t check the retainer-to-seal clearance at max lift and the retainer runs into the seals. The best seals for street use are the OE-style Viton seals. They let just enough oil past the seal to lube the valveguide for long life.

On the transmission side of things, it depends how much money you have left after your engine rebuild. Yes, going with a 700-R4 would be great for an all-around cruiser/performance build. The stock converter in your TH350 trans will work with the Xtreme Energy 262 camshaft. This is where the 15/8- versus 13/4-inch primary tubes come into play. The 15/8-inch long-tube primaries will build more slow-speed torque below torque peak to get your truck moving. If you see any penalty at higher engines speeds it would only be a few ponies. Go with the 15/8-inch headers.

Again, thanks to you and your fellow Navy enlistees for keeping us safe and free, and hope you’re in the States soon. CHP

Sources: compcams.com, federalmogul.com, summitracing.com

Hen’s Teeth

Q. I have a ’69 Chevelle. It had auto tranny shift on the column, and I recently converted to a floor-shift automatic. Can you help me find a place where I can purchase a sleeve to put over the column to go over where the original pin was? Thanks for your help.

Ray Samot
Via email

A. Surely, you’ve heard the term “rarer than hen’s teeth”? Well, 10 years ago you may have been able to find an N.O.S. shift collar for a floor-shifted ’69-72 A-body GM product. Those days are long gone. Just for giggles, we checked eBay and found one going for $40, which was a bargain! We also read that many people have hacksawed off the shifter spud on the collar and Bondo’d up the hole. They sanded and finished off the collar and painted it to the color of choice. No one was the wiser.

If you wish to step up to a very nice drop-in tilt-column, Flaming River has tooled up to reproduce the ’69-72 A-body tilt column for both column- and floor-shifted applications. Check out the mill-finished 33-inch tilt column (PN FR 30001), which comes complete with an ignition switch cylinder, the ignition switch, and a turn signal switch. This column is offered in mill finish, black powdercoated, and polished stainless.

Unless you have found that hen with teeth, we’d search eBay for a while and see if one pops up. If not, you have a couple of choices based on your budget. Enjoy your Chevelle!

Source: flamingriver.com

COMMENTS

TO TOP