Q: I have a ’72 Chevelle SS with a 355 ci. My rotating assembly is basically stock except for a decent set of forged pistons. For heads I have the 23-degree Trick Flow aluminum with 195cc intake and 64cc combustion chambers. I want to build a stroker engine but would like to keep my current heads to save some money. Any suggestions on what’s too big for these heads would be appreciated. This car is just a street cruiser that needs more grunt.
A: We would have no problem using 195cc inlet port heads on 400-plus cubic-inch engines. You said you’re looking for grunt to move your heavy Chevy. Going with a 3.75 stroke keeps everything simple. However, we would look to a new block to get the bore out of 4.125 inches. A 406 would be a nice addition to your displacement. The 195cc heads will make great midrange torque, and when it starts running out of steam from the stroke, the heads will run out of air. Good luck and enjoy your engine build.
Used Corvette Parts?
Q: Hello CHP! I have a cooling issue in my ’95 Chevy S-10. It just so happens that I’ve committed the greatest sin of all with this truck and dropped a small-block 350 in it with a TH400 backing it up. The 350 has a 0.512-inch lift hydraulic flat-tappet cam advance of 4 degrees, an Edelbrock Quadrajet atop a 1-inch spacer, and a cast-iron intake. MSD Street Fire HEI distributor and 8.5mm super conductor wires handle the ignition. The 350 exhales through Patriot conversion headers to 2.5-inch Flowmaster 40s. The TH400 has a B&M 3,500-stall converter, shift kit, and an adjustable-vacuum canister on the housing. The trans is still fully automatic, and shifts seem a little delayed after I shift up. There is a stock replacement Corvette radiator trying to keep it cool, and it still likes to climb up toward 250 degrees. I can never seem to keep it cool enough to get it streetworthy let alone track ready. Any advice to help my truck see the street?
Kory A. Schultz
Two Rivers, WI
A: Kory, there are many greater sins. We’re going to take a shot here; for the coolant temperatures to climb to the 250 range there are few possible culprits. Yes, there could be cracks in the heads or block, but we think it may be something simpler. You said you’re using a Corvette stock replacement radiator. By chance, are you using one of the nice aluminum water pumps off a Corvette donor car? The pumps are very nice as they are the short water pump design giving you more accessory drive and radiator room in front of your small-block, but they’re designed to run with a serpentine drive setup and in a reverse rotation from the crankshaft clockwise rotation looking at the front of the engine. If this is the case, your water pump is moving next to nothing. Make sure you’re running the correct rotation water pump for the front accessory drive system.
Next, you didn’t go into what type of fans you’re running. Climbing to 250 in quick fashion isn’t going to be stopped by a fan. You could drive the truck down the freeway at 60 mph, and the airflow through the grille should keep the engine cool if everything is correct with the engine and water flow. Make sure how you have the radiator mounted keeps the hot air in the engine bay, and cool fresh air in front of the radiator. If the hot used air has a chance to bleed in front of the radiator, the temps will continue to climb.
As for your transmission shifting, it’s not uncommon that a manual shift may be slightly delayed. You didn’t say if the shifts are firm when they occur. If the shift is solid and firm we wouldn’t worry about the slight delay in shifting. You can always compensate when you shift the truck to hit your rpm target.
Couldn’t Have Said it Better!
Q: Thank you and CHP for keeping us up on the latest this great hobby has to offer as well as protecting it for our children. Just because we trade gas for horsepower doesn’t mean destroying our sport would make any difference in the national usage of fuel or creation of pollution, but it would drive thousands more average income, but exceptional, Americans out of work. The trade-off would not be worth it. More gas is probably used driving to football games, so where does it all stop?