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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Engine Blocks

  • Thread starter Thread starter golf4283
  • Start date Start date Jul 10, 2009

golf4283

Active Member
May 30, 2003
1,253
1
39
Orland Park, Illinois
Jul 10, 2009
#1
  • Jul 10, 2009
  • #1
So I got a quick question about engine blocks that maybe someone can help with.

I have 2 302 blocks. The first is a 1974 block which is in good shape. The second is an '85 roller block which sadly isn't in the best of shape.

I currently am running the '85 roller block but noticed that the block itself is cracked where a couple of the bellhousing bolts secure into the block itself. I don't htink it's a structural problem as far as the engine running but it probably isn't good.

My question is is it possible to swap all the engine internals from one block to the other and what work would I need to do in order to do this. Obviously the '74 block isn't a roller so that's most likely gonna be a problem.

If it is possible though I would like to give it a try. Thanks for any help.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Jul 10, 2009
#2
  • Jul 10, 2009
  • #2
The rods and pistons will swap over, if the bore sizes are the same. The 85 crank is machined for a 1 piece rear seal, it lacks the flange forward of the seal area the 74 block is machined for. The roller lifters won't work unless you buy a 300-400 dollar reduced base circle cam, then drill and tap the lifter valley floor for the lifter retainer hold down bolts. The decks are taller than the 85 block too.. If I were you, I'd look for an 86-up roller block to swap the internals to. The 86-up roller blocks got 6 more pounds of iron added in the decks and bottoms of the coolant jackets to stiffen the bores.
 

bikefreak600

Member
Dec 10, 2005
157
2
19
rochelle IL
Jul 12, 2009
#3
  • Jul 12, 2009
  • #3
brand new ford blocks are really cheap from summitracing.com, last i knew they were only $300, you might get by just swapping parts but just install new rings and bearings, and it should last a while for normal driving. if you find a used block, your parts will wear much quicker or it might possibly leak cylinder compresion, and you would spend alot more in the long run. you could just swap everything into a used block but performance most likey will lack and engine wont last long. and you CAN NOT reuse head bolts and gaskets.
 

bikefreak600

Member
Dec 10, 2005
157
2
19
rochelle IL
Jul 12, 2009
#4
  • Jul 12, 2009
  • #4
sorry i just check summit and jugs and they dont list the stock production block on thier websites. they used to be really cheap
 

golf4283

Active Member
May 30, 2003
1,253
1
39
Orland Park, Illinois
Jul 12, 2009
#5
  • Jul 12, 2009
  • #5
Yea I'm just gonna find a 351 block and start my own build. This 302 will last a while I'm sure plus I got it for dirt cheap so I really don't care.
 

Rusty67

20+ Year Stangneter
Dec 3, 2002
3,749
37
109
LA, CA
Jul 13, 2009
#6
  • Jul 13, 2009
  • #6
Junkyard 5.0 blocks are ALL over the place and most of them run well, some even run really strong.

I wouldn't put a 351 in the 65-66s. Sadbuttrue has one in his 65 and let me tell you, it was a royal pain in the ass to work on the front suspension.
 
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