460 Shortblock differences

[caseydt]

Does anyone here know what the differences are (if any) on the 460 shortblock between the 70's block and the late 80's block? In looking for engine components some manufacturers list one rebuild kit for all 460's from 72-96, and others have a cut-off at 86 to use a different kit. I know they switched to fuel injection on the 87's, so the top end will be different, but is the short block interchangeable between a 94 and an older 70's block?

Thanks

[Woodz428]

I don't think it's the block that changed, but the top end. This would alter the parts needed for that and make the overhaul set different.

[427sharpe]

Deck height changed in the early 70's and again in the 80's as compression ratio fell. The deck on 68-70 blocks is 10.3", 70 1/2
is 10.310 and 72 and up 10.322 inches. Combustion chambers also grew, 68-71 have 75.8cc, 72-74 are 91.4 cc and 75 up 96.2 cc. Compression ratios equalled 10.5, 8.5 and 8.0 respectively.

[caseydt]

thanks for the info guys, from what I understood I can swap the shortblock without any problems then right? I will just need to calculate out the proper compression. I have a '94 460 from a F-350, complete with the the acc. and fuel injection, but I was going to order a new shortblock and swap the top end from the '94 over, just wanted to check to see if it would work before I spent the $$ for the shortblock.

Thanks again.

BTW I tried searching but I didn't see any, has anyone else tried to use the late model truck FI 460 in a cobra?

[cobrashoch]

Whooa there a minute. Somewhere late 80's to early 90's Ford changed the crankshaft at the mains design, and switched to a internaly balanced design I think. I'd have to look it up to be sure but you may run into flywheel and damper balancing problems by switching to a earlier shortblock. You are correct that you can use the late model fuel inj. stuff on the top of any 460 factory iron head/block combo though. But there will be port matching issues that will have to be dealt with unless you use the very, VERY lo/po' 94 and up heads. Most of the guys that I've talked to say that you will be disappointed with the power performance of the late truck fuel injection setup. ALL agree that there is even less you can do with it later, when you get around to modifing it, and trust me you will,,,,,,,,,,,,, Tractability issues are favorible as long as you stay with the stock F.I. cam, but who does? There probably is smarter AND cheaper ways to do a Cobra. A word to the wise.
Cobrashock

[wboss429]

for my customers that want cheap horse power,

i use the 87 or 88 and newer short block,(and yes late 78 and newer has a ex balance,older per 78 has a netural balance,flywheel and weight behind damp will have to be used from late engine,now put a dove head on,and a good intake and cam,and go

ps the late 88and newer have flat top pistions,and scj rods from the factory,now called truck rods,which started in 79...........which
r better than the scj's because of more meat on top of small end,




wboss