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Discussion Starter #1
Okay. I went back to the old forum, and did a search for the 351 heads on 302....
Found some good info. Here are a few questions it didn't answer.

I'm purchasing 70 351W heads, for $100. What should I get with it? Valves, Springs, etc?
I assume the valves would be different sizes for the intake and exhaust?
Or would my 302 valves work? (yeah, this'll show you how much I know about engines)
I know the 70 heads are the ones I want, any work that should be done on them
before I bolt 'em on?

Will the standard 4bbl intakes still fit on top there, or am I going to have to get a
351 4bbl intake to match up with the heads?

We have the engine down to the heads (the darn water pump won't come off..
stuck bolt on the right side, ARG!) and found it looks really clean. We were going
to get the 302 heads redone but after this deal came along, looks like 351 heads
now.

One other question. I checked in my "How to rebuild Ford Small Blocks" book,
and found the chart in regards to compression vs. headsize or whatever.
Originally my 78 302-2V was a compression of 8.4. I took that line across, and
found the corresponding vertical line for the 70 351-2V heads. That number said
8.7. So it correct to assume my compression will go up to 8.7 with the addition
of these heads?

Thanks guys.

Rich
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'66, 302-4bbl, Granada disk brakes, etc, etc...
 

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Discussion Starter #2
Shoot, forgot to ask...

Will the 302 valve covers fit on the 351 heads, or will I have
to get new valve covers as well.. (yeah I know, the stock blue
Ford ones are just SO sexy. :))

Rich
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'66, 302-4bbl, Granada disk brakes, etc, etc...
 

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351 heads are completely interchangeable on 289/302's... the C/R will depend on the type of piston you're running and whether it's a 289 or 302....the drop will be less on the 302 with the same piston top because of the longer stroke...

Complete rebuild....new valves, install hard seats, new guides, springs, retainers, keepers....minor porting work if desired...
I'd go with a 1.9 intake and a 1.54 or 1.6 exhaust valve and install screw-in studs and guide plates.

Use the 289/302 manifold and valve covers....you may need taller ones if you use roller rockers. 289/302 exhaust will work as well...

Just imagine a better flowing 289/302 head and you have the idea...


Browse through some of the engine articles here to glean some more info....

Good luck!

Pat
http://albums.photopoint.com/j/View?u=1570936&a=11937754&p=42910787.jpg
 

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Discussion Starter #4
Right now the Intake is running 1.78 and the Exhaust is 1.48 or something like that.
Those are the numbers I was quoted, it could be wrong.

I'll be sticking with the 302 pistons as well.

I don't think I'll go with the roller rockers... Just stick with most of the stuff that's there
now. How much more would that cost to convert over to that?

Rich
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'66, 302-4bbl, Granada disk brakes, etc, etc...
 

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I'm getting ready to do the same conversion. I would pony up the extra $ for the screw in studs and guide plates while you have the heads off. Without the guide plates (and the screw in studs they require), you're rocker arm choises become severely limited.

You need different head bolts for the swap, as I'm told.

If you always do what you've always done,
You'll always get what you've always got
 

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Camachinest has given you all the info you need..Your 302 Intake will fit right on. The 302 and 351 heads are exactly the same size..its a nice swap and will help breathing...you will need special head bolts for the swap..the 302's are drilled for 7/16 bolts and the 351's for 1/2 inch..you can get a set from PAW or Ford motor sports..you might think about milling the heads..this will bring your compression back up..the bigger chamber 351's will cause a slight drop
 

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I'd estimate 350.00 for the conversion including machine work if you use a budget minded rocker like the Crane Energizers that I use on the race car...

Your stock valve sizes on the 351W are 1.84 intake and 1.54 exhaust IIRC..

The sizes you noted for your 289/302 are good...

Pat
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There are two choices, actually. The preferred, aka best, are the ARP step down head bolts. From Summit, memory serving, is about $130. The other method is using a type of washer, i think. I've never looked into this option very much. I was going to use the head bolts.

Rob
Member: Slightly Modified
66 coupe 302
66 fastback 351W
 

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Discussion Starter #9
what are the standaard ones used in a 302? Also, what are the different rockers available?
I've heard roller rockers and rail rockers? am I close? When it gets to these parts down in
the engine, I'm clueless. I'd rather be able to get as much HP as I can, with spending as
little as possible. So if I get 10 hp difference out of $350, I might just stick with what I got, if
I can do that....

Rich
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'66, 302-4bbl, Granada disk brakes, etc, etc...
 

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I used those on one of my racing engines with W heads...

I've also used stock (new) bolts with a hard (grade 8) washer underneath the head...

The dowel sleeves locate the heads so IMO a shoulder isn't all that necessary....the hard washer takes up about one thread of engagement...still more than the spec of engagement length for standard grade 8 fasteners...

Just supplied as an option in case the special bolts aren't readily available when he needs them...

Pat
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I have also used regular 302 head bolts for this swap and have never had a head gasket blow out ..not one bit of trouble..between the dowl pins and the weight of cast iron heads..a damn stapler would hold em..*LOL*
 

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Take a look here for some different options depending on the year of your engine....

Early (pre-77) engines use studs so it's possible to use a rail-type roller rocker....ask Johnpro...he just did that swap

Later engines or heads use pedestal rockers that bolt on....



Pat
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Discussion Starter #13
I have a 78 302 I'm bolting this onto.

That was one of the things I was worried about. Rocker types. I'd like to just use what I have now, if that were possible. If I'm going to a 78, is that going to be a major problem?

Rich
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'66, 302-4bbl, Granada disk brakes, etc, etc...
 

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ok....'70 351W heads on a '78 302....

The valvetrain parameters will run with the heads...

Browse through that online catalog I posted and look at some of the descriptions for rocker arms....

Also, you'll need to get the right pushrod length....

I haven't built any later engines so don't have the practical experience you need.....but there are a number of folks here who have and can help...johnpro is just one of many...

Pat
http://albums.photopoint.com/j/View?u=1570936&a=11937754&p=42910787.jpg
 
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