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Old 08-07-2024, 08:46 PM
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So the original plan for the engine was to use parts I had laying around to put something together, unfortunately the original 360 block I planned to use was no good(cam bearings were loose) so that block got used for mockup and a 68/9 390 block and crank I picked up rough and cheap got sent to the machine shop. Where it all still currently is.

I started ordering parts planning to do a 12.5:1 390 with my tunnel ram and twin Dominators. But a mistake I made ordering pistons turned into something better. The pistons that showed up from weisco are dished pistons, putting my compression ratio at 10:1 at the best. But when something like that happens the best thing to do is bolt a blower on it. So I picked up 3 8v71 Detroit diesel blowers(1 is actually for a 92 series). And I’ve ordered all the parts to convert one to gas use. AMC blower manifolds are incredibly expensive, so I sourced an Offenhouser dual quad manifold and sent to a local machine shop with the blower for mock up. He’s going to modify the Offy manifold and weld a plate to it to mount the 8v71 blower.

Otherwise the engine is a .030 over 390 with forged Weisco pistons and Molnar connecting rods. Crower is making a custom cam for the blower(they’re also taking back the other cam I originally ordered for the higher compression build so I can’t recommend them enough). It’s going to be a solid flat tappet custom grind with about .550 valve lift and 114 lobe separation. The heads are ported 1970 390 291C cylinder heads. I’m hoping to make between 8-10 pound of boost with the blower.
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