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Okay, so I've got a 1970 C-10 with a 350 in it. Ideally, I think 350-400 horsepower would make me happy for a long time. The caveat, however, is that I'd like to achieve decent mileage and reliability, do it cheaply, and run it on 87 octane. For all of these reasons, I think a 400 is my best choice. I think a 375 horse 400 will be much easier to live with than a 350 making the same power. I'm not interested in building a 383.
My design goals call for a horsepower peak of arond 5000 rpm, with maximum rpm's of 5500, although I will be plenty happy if either of those numbers winds up lower. The only real trouble I've run into is that the selection of available, affordable pistons is limited, and, obviously, I need to keep the compression ratio in check to run 87 octane. So, here are two possible combos; I welcome all input.
Engine 1:
-0.030-over 400 block (4.155 bore)
-3.75 stroke stock crank
-5.565 stock rods
-Speed Pro 12.5 cc dish Hypereutectic pistons
-Edelbrock E-Street 70cc heads
-10.0:1 Static Compression
-0.045 quench distance
-Comp Magnum 270H installed straight-up (single pattern, 270 adv, 224 @ 0.050, 110 LSA, intake close @ 65* ABDC)
-7.9~8.0:1 Dynamic Compression (depending on calculator used)
-Edelbrock #7104 Performer RPM Q-Jet manifold
-QuadraJet carb
-1 5/8" Headers, 2.5" duals
-HEI
Engine 2:
-0.030-over 400 block (4.155 bore)
-3.75 stroke stock crank
-5.565 stock rods
-Federal Mogul 24 cc dish cast rebuilder pistons
-Edelbrock E-Street 70cc heads
-9.0:1 Static Compression
-0.045 quench distance
-Comp High Energy 268H installed 4* advanced (single pattern, 268 adv, 218 @ 0.050, 110 LSA, intake close @ 60* ABDC)
-7.2~7.5:1 Dynamic Compression (depending on calculator used)
-Edelbrock #7104 Performer RPM Q-Jet manifold
-QuadraJet carb
-1 5/8" Headers, 2.5" duals
-HEI
So, what do you guys think? I liked the Hyper pistons, with a smaller dish and more quench area, but it seemed like I would need more cam, installed straight-up, to keep the cylinder pressure in line, and this would probably negate most benefits from the higher compression... although, the cylinder pressure in #1 will still be higher. Will it run on 87 octane? Will it be happy at 1600 rpm on the highway with a 700R4 and long gears?
Which engine is better for my goals? Neither? What would you change, and why? Perhaps someone could crunch the numbers in a desktop dyno for me...
My design goals call for a horsepower peak of arond 5000 rpm, with maximum rpm's of 5500, although I will be plenty happy if either of those numbers winds up lower. The only real trouble I've run into is that the selection of available, affordable pistons is limited, and, obviously, I need to keep the compression ratio in check to run 87 octane. So, here are two possible combos; I welcome all input.
Engine 1:
-0.030-over 400 block (4.155 bore)
-3.75 stroke stock crank
-5.565 stock rods
-Speed Pro 12.5 cc dish Hypereutectic pistons
-Edelbrock E-Street 70cc heads
-10.0:1 Static Compression
-0.045 quench distance
-Comp Magnum 270H installed straight-up (single pattern, 270 adv, 224 @ 0.050, 110 LSA, intake close @ 65* ABDC)
-7.9~8.0:1 Dynamic Compression (depending on calculator used)
-Edelbrock #7104 Performer RPM Q-Jet manifold
-QuadraJet carb
-1 5/8" Headers, 2.5" duals
-HEI
Engine 2:
-0.030-over 400 block (4.155 bore)
-3.75 stroke stock crank
-5.565 stock rods
-Federal Mogul 24 cc dish cast rebuilder pistons
-Edelbrock E-Street 70cc heads
-9.0:1 Static Compression
-0.045 quench distance
-Comp High Energy 268H installed 4* advanced (single pattern, 268 adv, 218 @ 0.050, 110 LSA, intake close @ 60* ABDC)
-7.2~7.5:1 Dynamic Compression (depending on calculator used)
-Edelbrock #7104 Performer RPM Q-Jet manifold
-QuadraJet carb
-1 5/8" Headers, 2.5" duals
-HEI
So, what do you guys think? I liked the Hyper pistons, with a smaller dish and more quench area, but it seemed like I would need more cam, installed straight-up, to keep the cylinder pressure in line, and this would probably negate most benefits from the higher compression... although, the cylinder pressure in #1 will still be higher. Will it run on 87 octane? Will it be happy at 1600 rpm on the highway with a 700R4 and long gears?
Which engine is better for my goals? Neither? What would you change, and why? Perhaps someone could crunch the numbers in a desktop dyno for me...