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Looking at purchasing a 1974 302 would this be a good choice to build from. It will go in a 68 mustang coupe or should I stay with earlier years?
 

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I think that the compression on a '74 will be very low. Perhaps in the 8:1 range. So to raise the ratio will require different heads or pistons. Unless 8:1 is all that you require.
 

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Unless you're buying a fresh rebuild or ordering from a crate engine supplier and you'll be installing it as is, the year of the engine doesn't make much difference. Any 30+ year old used engine should be taken apart for inspection and new rings and bearings as a minimum, at which point it isn't a big step to change pistons or go for a complete rebuld. Any 302 block will take any 302 piston, any 302 heads, any 302 timing cover, any 302 water pump, etc., so you can build whatever kind of engine you want from any year 302.

P.S.-if you're looking to do a performance build up using the stock short block take into consideration that only the HiPo 289, Boss302, and late model 5.0 ever got anything beefier than regular production pistons, rods, or rod bolts so regardless of which year you start with these area will need to be addressed to add reliability to a performance engine build.
 

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I currently have a '74 302 block with a bit of a cam, flat top pistons and '68 heads that have been worked a bit. It is a good platform to start with in my opinion. FWIW I am in Northern CA and have a spare '68 2V long block on an engine stand. Bought it from another VMFr who came by so I could listen to it before he pulled it prior to putting in his rodded SBF, and it sounded ok, but I never took it apart so I don't what kind of shape it's in. I then bought another engine, a finished and balanced '66 289 short block and have subsequently picked up a set of modified '66 289 heads so I don't need the 302 any longer. If interested, send me a PM?
 

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Rickmaan said:
Unless you're buying a fresh rebuild or ordering from a crate engine supplier and you'll be installing it as is, the year of the engine doesn't make much difference.
Well, not exactly, Beginning in, I think 72, Ford cast "smog bumps" in the exhaust ports of the factory head. These obstruct the flow, which degrades performance. I believe the 74 302 was the lowest rated hp/torque, of the 302 engines. The factory cam profile differs between certain years as Ford began compensating for EPA smog requirements. Also, the front dress on the block changed in 1970. As noted above the water pump outlet was reversed to the other side of the engine, which also meant the timing pointer was re-shaped and mounted on the passenger side of the engine. The 1970+ timing pointer is not reproduced, to my knowledge, and is hard to find. Despite my repeated emails to NPD, they never changed their catalog advertising and still claim, and sell, the same pre-70 timing pointer for applications through 1973.






Rickmaan said:
P.S.-if you're looking to do a performance build up using the stock short block take into consideration that only the HiPo 289, Boss302, and late model 5.0 ever got anything beefier than regular production pistons, rods, or rod bolts so regardless of which year you start with these area will need to be addressed to add reliability to a performance engine build.

The 302 block made in Ford's mexican plant was manufactured for use in trucks and buses. It uses the HiPo size main bearing caps and also has stouter webbing in the block. Contrary to some reports, according to Ford the nickle content in the cast iron is identical as between the Mexican and non-Mexican made 302 blocks. Consequently, the 289 HiPo block and the Mexican 302 blocks are preferred for building a modified engine, unless one is to go to an aftermarket block, such as Ford A4 block, that has 4-bolt main caps, or now, the new Boss 302 block, which is a siamese bore 302 with screw in freeze plugs, oil galley plugs, and 4 bolt main caps.
 

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I used a '74 302 for my block. And used '69 heads that were ported and polished and 351W valves installed with Keith Black .200 high top pistons and a pretty big cam, Now I must use 50/50 mix of race gas(110 octane) and super so I don't get spark knock.
74 block is fine just build it right.(junk the heads)
 

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Daf said:
I figured the compression would be lower, I'll stick to finding an earlier year. Thanks
Huh? If you're building it, why does that matter? ;)
 

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I am using a 79 302 for my 331 stroker build(never thought about the water pump outlets being different than my 289s)and I just purchased a brand new 3 core radiator right before I decided to build a new engine(money just flies out of my pocket these days)so now I have a brand new Centerforce flywheel,OEM clutch and 3 core radiator that will be of no use to me...Great

Dave
 

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70sportsroof , while your comments are all valid you seem to be missing my point, maybe I didn't explain it very well. The point I was trying to make is that if you're buying an engine to build the minor differences that come with specific model years are not a big deal.
-Yes, smog heads suck but so do most SBF oem head castings, smog bumps can be removed but they all need work for a performance engine or cost permitting just replace them.
-Yes, smog era oem cams were weak on performance, but how many people building a performance engine keep the stock cam?
-Yes, the front dress and brackets changed from year to year, but they all will bolt on as a complete set to any other year block.

As far as Mexican blocks go, they got some press in the mags and I've heard other people talk of the beefier mains but quite honestly I've not seen a street engine bust a block other than throwing broken rods through it, and the few times I have seen a production block give up it cracked right down the lifter valley and under the conditions of the failure I doubt a Mexican or HiPo block would've made any difference. If you can find a Mexi for a build that's great, but I wouldn't worry over not having one for a street engine.

So I stand by my original post, but I'll clarify it a bit more. If you're buying a fresh engine and it's internally stock and you'll be installing it as is then year to year differences are important, but if you're buying something to build (as the OP inferred) and you'll be tearing it down and buying new performance parts, then any year engine is as good as any other to start with.
 

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IMHO, if one is going to run cast iron heads, all other things being equal, I would start with the smallest chambers.
 

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Yeah, I agree. If you are adding aftermarket internals, then your choice of ford factory blocks is reduced pretty much to roller or non-roller. Getting into the A4, Dart, World or Boss302 blocks is $$$$. My dream block is an aluminum siamese bore 351 block with a tall deck and bolt bolt mains. Meanwhile, I have a Mexican 302 block sitting in the shop which I hope to retrofit to a one piece rear main seal and 4 bolt mains, then build it for a 450 hp supercharged 337 stroker "someday".
 

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Dave, I don't understand your issue with parts fit. You can bolt on a 289 timing cover and use your 3 core radiator. As for the centerforce, the bolt pattern is the same on the 79 and earlier cranks, the issue is simply matching the balancer to the weight on the flywheel, plus the bolt pattern for attaching the pressure plate. You can get a starter to match the tooth count on the ring gear. With planning you should be able to use all of the parts you bought, on your 79 block. Maybe I'm missing something.
 

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I have a 74 302 block in my car with 66 heads. Put 10:1 pistons in it and a mild cam. I didnt run into any fitment issues using the 66 style water pump and accessories. I specifically chose a 70's block because of the Hipo sized mains.
 
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