Thread: How to tell the difference ( H.O. or not)

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Hello all. I bought an engine from a junk yard that is supposed to be a 1985 302. I pulled the torque specs offline for the bottom end and began my torquing. I snapped a main cap bolt on the first cap I tried to torque. I called the local speed shop and was informed that the torque spec should be 70 ft/lbs instead of the 105 ft/lbs that I had torqued to. Upon further research online I found that the 85 302's are H.O. (high output) and the pre 85 302's are not. The torque spec I was using was for the H.O. and the torque spec I was given by the speed shop was for an earlier engine.

My question is this. How do I verify that this is indeed an 85 H.O. engine? I really don't feel comfortable trusting the word of a junkyard.

An additional question I would likeanswered is; what are the differences in the two engines? Just a general description is fine.

Thanks again

1984 is carbed 1985 is cfi and 1986 is f.i.The one way to tell on the 85 is the air cleaner,dual snokel and should say h.o. on it.You could get the numbers off the heads and engine and someone maybe able to tell from those.The 85 should have central fuel injection and aluminium valve covers that say powerd by ford and have a flat tappet cam and was rated at about 190 hp.
Did youy rebuild this motor ,why were you messin with the mains?Its not really a good idea to just start torquing things down.Most of the bolts on the bottom end clamp things down from bolt stretch and are only really good for one stretch,the mains are a little different bolt,but the same principal.
I have never heard of a main just coming loose ,without a problem thats not going to be fixed by torquing them down.

It is carburated. All post 84 302's did not have fancy valve covers etc. They offered that engine in the trucks and those weren't dressed up. This one has stamped steel valve covers. The engine is painted grey if that means anything. The reason I took the bearing cap off was to check for wear.

Need some head and block casting numbers and date codes to decipher for sure which engine it is. Can't believe a junkyard would be telling stories about an engine!!!!!

85 mustang gt was carb motor. Also same firing order as a 351

I'll try to get some #'s today

Originally Posted by dennis kelley

85 mustang gt was carb motor. Also same firing order as a 351

Yes, if...... it was a 5 speed. the automatics had throttle body injection.

OK. I have some #'s. On the head I found 3K8 .
On the block I found 3J12 (around the flange where the bellhousing will bolt up)
On another spot on the block I found EOAE & D3C .

Do these mean anything to anyone here?

Any help is appreciated.

Thanks

Look on the underside of the head that overhangs the lifter valley. There will be a four digit/letter casting number there. If it is an 85 HO motor it will have E5** there. Also the 85 HO was a roller cam with the aforementioned 351 firing order and vacuum advance distributor with a machined steel gear. The pistons would also be forged TRW's. It also had a double roller timing chain. Don't be surprised to find the much more common generic 86 and up roller 302 in just about anything and the boneyard calling it HO.

Originally Posted by Oldf100fordman

Yes, if...... it was a 5 speed. the automatics had throttle body injection.

Found that out the hard way on an 89 HO. HO uses the 351W cam which is a different firing order from the 302. Check your firing order if the wires are still on it.

The early 5.0 fired 1 then 5 which was hard on the front main which brought the 351 w firing order in later engines. I have a 84 HO with factory Holly 4 and Ford aluminum intake and shorty headers and alum valve covers saying POWERED BY FORD on them .. This one was pulled from a Capri which was the test mule for the next mustang year . In 1984 the HO was rated at 187 HP. Some early 1985 5.0 still had hyd lifters and then they went roller.

Do you know what the engine was out of?? Iv found the later 86/87 HO 225HP engines in the Lincoln LSC(i think) which are alot more likely to not have been abused, got mine for $350 complete intake-pan, just my .02

That should be an LSC mark seven or some such. They are good candidates for track lock disc brake rears as well. First clue in a junker car is the HO will have the throttle body on the passenger side. Still, it isn't unheard of to find a generic crate replacement motor that is non HO in there so you have to check further. The 351 firing order, double roller timing chain, forged pistons, E7TE heads, of course the roller cam is a maybe because it could still be the generic cam with just short of 3/8 valve lift. The HO cam has .444" valve lift. The valley on an HO block usually has XXX but may sometimes have YYY cast into it as well.

like these x x x on the block this a 84 carbed engine

yes except the lifter bore is taller so the machining almost cuts into the XXX.