visualsmoke

The car this engine will go into is a 1980 Corvette. I want a BBC in it of approx 500-540 cubic inch. I’m after low-end torque for the most part. I will keep the stock 3.07 rear gears and will use a Richmond 6 speed with the .062 6th gear. Online calculations indicate approx 70MPH at 1700-1800 RPM in 6th with 26” tall tires. So, the motor has to be making good torque approx 1500. Maybe a max RPM of 5500? I would like the compression to be pump gas friendly, and the cam be a hydraulic. I’ve heard big cam numbers mean less with big inchers as opposed to smaller BBC’s. True? So, with this in mind, somewhere in the .550 lift area? Recommendations on duration? I want a stout lower end as I’d like to keep the option open for a belt driven supercharger like a Vortech, and not have to redo the bottom end. So, steel crank (4.25” stroke in a .060 over bored 454 block =496 CID?), 4 bolt mains, forged pistons (9.0 to 1 for pump gas?) ? Rods? H-Beam? I’ve heard different length rods (+ .250) will reduce side loading with stroker cranks. True? If so, are the pistons special (pin higher up in piston?) and more expensive? If so, how much more? Now, the part I’m really lost. Heads. I understand the basics of the smaller BBC’s like 454 & 427’s, and the rectangular port vs. oval port theories. But, I’m unsure about bigger inch motors like I’m planning. I’d like aluminum heads. Rectangular or oval? Open or Closed chambers? CC’s of combustion chamber? Intake port volume? Should they be O Ringed in anticipation of the blower? I’d REALLY like all this to fit under the stock hood, so I’m sure the intake manifold selection based on hood clearance will hurt things a bit. Will this also affect the head choices? I’m planning on headers and 2-½” or 3” exhaust. I have a Flowmaster’d 3” dual system on my 427 BBC Nova and I definitely want the Vette MUCH quieter! The 3” seems to give weird harmonics that the 2-½ system I had on it before did not have. Thanks so much for your input.

godtfred

Please be aware of the 80-82 corvette aluminum diff is fragile and not suited to run behind a large bigblock, also the Richmond 6 speed are too weak to last very long, you will in my opnion need a toms diff with axle kit and a gforce transmission or similar.