Thread: whats the difference?

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I'm looking at building up a nice 390ci for a street rod and am looking for an engine to build. I have been offered a couple of truck engines which seem ok but what I don't know is there any major differences between these and passenger car engines.I appreciate they might not initially have the same power but can they be made to perform with if nec. different heads etc etc. Is interchange with pass. car engine parts a problem?
thanks in advance.
Hudsonguy....

interchange is completely fine.... the truck engines just have larger chamber heads...

It also depends if they are FE or FT truck engines. Some FT (330, 361, 391) engines have the heat crossover in the center of the head and intake. Also small valves and really big chambers. 330, 361 and 391 truck blocks need the dizzy bushing replaced to fit FE dizzys. The bushing is cheap and still available from Ford. Easy nuff to do. Most truck block castings were heavy duty and sport the triple webbing or "crows feet" cranksaddle area. Also check the cyl wall cores as some FT blocks were cast with 428 cyl wall cores. Not all but some. Also the 330,361,391 FT truck cranks have a larger snout diameter and use a differnet timing chain cover. So if you use a FE crank of any flavor you need a FE timing cover. Again no big deal. Most of the 70's truck 360's and 390's used the D2TE-AA heads. They have hardened seats for unleaded. They are the same casting as the earlier C8AE-H heads used on 352, 390, 428's etc.... So compare these things to the engines your looking at and see what's what. Dave Shoe's "drill bit test" will tell you what cyl wall cores were cast in a paticular block. It's a very simple field test. You'll need to knock out a few block freeze plugs to access the cyl wall cores. Gap the space between the cyl wall with drill bit shanks. A 352/360/390 will snugly fit a 17/64" drill bit shank. A 13/64" drill bit shank will fit snugly for 406/428/391. A sonic map will net the best results and also note coreshift for max overbore. But this test will at least tell you what cyl wall cores the block was cast with. Takes most of the guessing and BS out of "yea it's a 428 block" when your shopping. Also truck engines like the 360 used the same bore as the 390 4.05" but a shorter 3.50" stroke compared to the 390's 3.78". So you would need to still get 390 crank and rods. I'd look for a nice complete 390 so you don't have to chase around for other parts needed. The trade off is the truck blocks can be better but other than the block and maybe the heads and some rocker parts you won't use much else. Truck engines were also lower compression than the car engines. Every part can be ID'd by the part or casting number. Blocks being the exception here thus the reason for the drill bit test. If you can get the head casting numbers, crank number, rods, intake etc....I can tell you exactly what they are so you know what your getting before you shell out the cash.


G.

FFR428,
Many thanks, I appreciate your input. One comlete engine I will be buying anyway as it is really cheap, thats an early '70s 390 truck engine complete with exhaust manifolds (which I will use , either this set or similar) as I prefer the look at sacrifice of power compared to headers. This engine also has a bellhousing and clutch assembly, bellhousing is 6'' deep so should be ok with a toploader right? I've read somewhere that the 6 3/4 deep ones won't work. This particular one is alluminum are they OK? The other one I am considering again a 390 truck engine this time from 1966 also with a complete 3speed manual box which I probably won't use but it's there. So the plan is to make something with the best of both plus some aftermarket stuff and if I can find a few old speed parts like an intake or something even an old cast one would be great. I've yet to see the second one and as it's a few hours away I'll probably make a decision on the day and strike a deal and bring it home, was told it's good, can be seen running on a test bench with good oil pressure , low miles etc. Am I going the right way here?
Hudsonguy..