So could you run a 390 crank with 360 rods and pistons (in a 74 360 truck block) and bump the compression up to the 10s?

 

Not a good idea. The longer rods are real weak sisters and break with real power added.

 

I don't think that will even work at all.

1.892 + 6.542 + 1.778 = 10.21. (1/2 stroke, plus rod, plus compression height)

Deck is 10.17.

If you have a different length on the rods or compression height, add it up again.

390 crank and rods, 360 pistons will give you about 9.5. It seems 360 pistons are the same or approx the same spec as 390 2bbl regular fuel pistons from '66-'70 or so car engines.

So if you want 10's, you can get car pistons from the '60s that will work, or other aftermarket pistons that will work. It also depends on your heads cc size.

 

My 65' galaxie with a 390 came factory with 10.2:1 compression. Haven't had it apart and its still running good at 46 years old so I don't have any part numbers or measurements on the internals for you. It has the c4ae 6090g heads and factory 4v intake and came with a automate 4100 carb with 1.12 venturies which translates to right about 600 cfm. If you can find one of these or the parts you would be set. 300 hp and 427 ft pounds from the factory.

 

I guess 0.04" out of the hole might be a tiny bit too much compression... it was just a thought.

Actually I think 9.5 is about all I want... since the low compression 360 probably wouldnt like boost too much.... lol

 

Boost? Surely you jest...

 

there's an 88mm 1.00 TURBO from a PowerStroke sitting in my garage with no engine to call home....... but I know the bottom end of a 70s 360 won't survive....

 

Oh goodness, why was the first thing that popped into my head the idea of pulling a junk yard 460 just for the sake of giving it a place to sit, since those stock bottom ends have been run to well over 600 hp and survived I have a disease and the only cure is more hp

 

( ^ That's the fire burning under my *** to build all this ideas that pop into my everyday )

 

360 with 428 heads what do you think the hp also are the motor mounts the same as a 390 block?

 

HP about the same, mounts are the same as any post '65 FE block. 390 and 360 use the same block.

 

428 heads would lower the comp ratio on a 360 so whatever gain you had from the larger valves was lost on the lower comp ratio.