Thread: 302 build

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I admire your spirit. You're thinking outside the box. Here are a couple of my thoughts on this.

The early block is a 2-piece rear seal. The late crank uses a 1-piece seal. Have you figured out how to do this?

Will you be able to get high-compression L99 pistons off the shelf? The rods are longer, so the pin will be higher than a 302 piston. What about the L99 piston crown design and valve reliefs mating up with a Vortec chamber and valves?

If you can get around these issues and keep cost down, congratulations. The alternative might be to check with one of the hot rod Chevy dealers like Scoggin-Dickey and price a 302 crank. A 1969 crank should have had large journals and would be a drop-in in your 350 block. With 5.7 rods, you should be able to find off the shelf pistons for the required 11.0:1 static c.r. Use a solid lifter cam with an operating range of 3,500 to 7,500 with an intake closing point of 55 degrees after bottom dead center. This should yield a dynamic compression ratio of around 8.2:1. You should be able to run pump gas with it if you keep the squish at 0.035". You could do that by popping the piston out of the bore by 0.006" at TDC and running a Fel-Pro 1003 head gasket. At 7,500, the beast will inhale 655 cfm, so a 700 cfm carb should do the trick.