Daily driver small block build

junkyardhero said

with my interpretation a few G's is 2~3 and that, to me, is going to be the biggest hurdle to clear.

300 horse is a fairly low bar to clear, but with the 5.2 you'd still need to add about 70hp to get there.

i *think* the stock compression will support that, and with the right cam and intake and maybe justttt breathing on the heads makes it happen; and unlocks a boat load of torque, and likely all done by 5K or so.

with the 5.9 that goal is achieved a little easier.

either way, the whole operation hinges on getting an absolutely stellar core that needs practically nothing.

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Factory rating for 5.2 Magnum is net so that's with single exhaust and 1990s (restrictive) catalytic converter and beer-barrel intake that runs out of steam by 4500 RPM, plus factory EFI tune which needs to be emissions-friendly and minimize knock. Swapping on a 4-bbl intake and carb, distributor ignition with performance advance curve, and 2.25-2.5" true dual exhaust will free up a ton of power. Maybe not quite 70 HP but still a lot.

Most Magnum cores need zero machine work if they weren't totally abused, not uncommon to find 150k+ mile short blocks that still have cross-hatching on the cylinder bores and no ridge at the top. I found one at a junkyard a few years back in a 2000 Ram 2500, truck looked like it had been in a derbycross race but the engine was mint inside. I put new rod bearings in it and left everything else in the short block alone; bolted on a good top end (ported Edelbrocks and RPM intake) and put in a custom-grind hydraulic roller cam, reused the factory roller lifters and sent it. It's been in my '70 Duster for about 5 years now and still runs like a top.

If I had to do it again I'd still rather buy 3 5.9L Magnum cores and pick out the best of the bunch than find a crusty old worn-out LA 360 and do a full rebuild.