You have chosen some really good cylinder heads. You can't go wrong with either of the AFR heads. The larger-inlet 210s will push the rpm range higher at the expense of some slow-speed torque. It may be the right direction for you to go to make your T5 five-speed live behind your engine. We've also used the 220 Canfields with great success on a bracket 350. That engine with a 240/250 at 0.050 mechanical flat-tappet cam pushes a 2,400-pound Datsun 240Z into the low 10s at over 130 mph! For the rpm range you're looking for, we would suggest going with a single-plane intake like the Edelbrock Victor Jr. (PN 2903). This Victor Jr. is cast 1 inch taller to add plenum volume and is CNC-port matched, which will line up nicely with either cylinder heads. Check with Edelbrock for more information at 800.416.8628, or at edelbrock.com. As for a carb, the old standby 4779 Holley 750-cfm double-pumper will work well, with a good balance between drivability and high-rpm performance. You could go with a larger cfm (800 to 850) if you're just looking for all-out high-rpm horsepower.
Lastly, your 280H Comp Cams hydraulic camshaft is going to run out of air long before 7,000-plus rpm. If you really want to reach these engine speeds, we would recommend going with a mechanical flat-tappet camshaft. It's also going to need more duration and lift to let those killer cylinder heads breathe. Check with Comp Cams about the Xtreme Energy XS282S. This camshaft specs out at 244/252 degrees duration at 0.050 inch tappet lift, it has 0.520/0.540 inch max lift, and is ground on 110 centers. Combine this with your 1.6:1 roller rockers and you will have 0.555/0.576 inch max lift respectively. You will also realize a 2- to 3-degree increase in duration. Check compcams.com or call 800.999.0853.
With this combination, you will have one stout small-block pushing 475 to 500 hp and drinking up some of that really killer high-test you have for fuel. Have fun out in the countryside!
IMP ExhaustQ It's time for a new exhaust system for my '62 Impala SS. The 327 is mostly stock with a 500-cfm AFB with a '65 Corvette cast-iron manifold and a mild camshaft. I have a set of Rams Horn 211/42-inch manifolds and stock head pipes, both of which are new. I plan to use 50 Series Delta Flow Flowmasters with 211/44-inch tailpipes. This car is a cruiser and daily driver. Will this setup have any effect on the low end or economy?Jerry WillardVia e-mail
A You didn't mention what type of system you have on the car now. The factory exhaust, single especially, and also the stock duals are quite restrictive. From the factory system you should expect an increase in part-throttle torque and fuel economy with a set of Delta Flow 50 Series mufflers. A 211/44-inch dual system would be a good balance for your 327 powerplant. If you're looking for a full 211/42-inch mandrel-bent system check out the Flowmaster's American Thunder Header Back Pipe Kit.
Flowmaster offers a header-back dual-exhaust system that utilizes either our Delta 40 Series, Delta 50 Series, or Hushpower II mufflers. This pipe kit is sold under PN 17413 without mufflers and allows you a choice of the three muffler models to fit your taste in sound. The pipe kit comes complete with custom hangers to go to factory bolt holes in the frame for a direct fit. The system fits '59-64 Impalas and has tips that exit right before the rear tires. The lowrider crowd prefers this setup for their extremely dropped vehicles. For owners who want a factory outlet location, Flowmaster has also released a tailpipe kit (PN 1055) that connects to the header-back pipe kit and the exhaust exits at the rear fender line. The system is a full 211/42-inch mandrel-bent kit.
So for you 348/409 owners-or those guys that just can't get enough and have slapped a sweet big-block between the framerails-Flowmaster has a killer exhaust for these cars. You can check it out at 800.544.4761 or online at flowmastermufflers.com