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I just picked up a 1975 parts truck and the PO had purchased a working "390" motor that he later found out wasn't once he took it apart to rebuild (doh!).
I've inherited the mess and I am trying to understand some basics to see if I have most of what I need to build a 390. The info I have pulled off so far:
Block - C7ME-A with "352", bore 4.05" (I realize this doesn't mean much, will it work for a 390?)
Rods - C7TE-A (will these work for a 390?)
Pistons - say "3.90" and "4V" (will these work for a 390?)
Crank - 2T, measured to be 360 3.5" stroke - boo
Heads - C8AE-H - why are these on a 67 block?
There is a possibility I got some mix n match parts....
So I want to turn this pile of parts into a 390, and it seems like all I need is a crank. But I'm confused about FT vs FE parts, and I don't really understand the difference if any.
The casting number date codes are for engineering changes. It would not be unusual to find C7-- and C8-- codes from 1967 and 1968 in the same production engine.
The block with a 4.05 bore would be 360, 390 and 410. (410 '66 & '67 Mercury) 360 and 390 blocks remained the same through the run. In pickups, heads, cams, everything but the crank, rods and pistons are the same between engines.
Those rods are no doubt the long rod used in 352s and 360s. 6.54", vs. 6.49 for all other FE motors. They can't be used in a 390 with 390 car pistons.
The pistons are, as marked, are 390 4bbl car pistons. (flat tops with valve reliefs, right?) Ford used both 2bbl (dished with valve reliefs) and 4bbl pistons in 360s. With the shorter stroke, they end up down the hole over .100. (In pickup 390s, Ford used the 410 piston, again ending up down the hole).
You can use those pistons IF they are servicable, in a 390. Expect 10.5 CR. (depending on combustion chamber, gasket, and actual engine specs) Just add a 390 crank and rods.
Don't worry about FT parts. The heads have a different exhaust crossover & smaller valves. The cranks have a larger snout. Front covers are iron with an engine mount provision.
You may be able to use the heads, but they probably do not have hardened seats for unleaded gas. "D2TE..." heads came with hardened seats.
Mix and match parts--could all be from the factory.
Check above the starter for casting date on the block.
I do not know on the compression. We had a 9.5 CR two bbl "Regular Fuel" 390 in our '66 wagon. It soldiered on for years on Co-op swill gas.
For 9.5 compression, you would need the 390 car piston with a dish and valve reliefs.
The 390 pickup engine used the 410 car piston, with it ending up down the hole over .100, just like the 360. Compression was about 8.2. You can burn cheap gas, but low compression lowers torque, and reduces fuel economy.
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