[kleen56]

Has another put 351W heads on a 289 or 302 Ford? I was wondering if it's a straight bolt on and was there a increase in performance with the switch?

[4 Jaw Chuck]

Its a straight bolt on but you need hardened washer under the head bolts of the 289/302 because the 351W bolt holes are larger in diameter. Increase in power depends on what you upgrade to go with it, just a straight swap with no other changes and I doubt you will feel much of a difference.

[FEDDO]

depends on the 351 heads. some have the same size valves as the 302. using the 69-70 heads the valves and ports will be larger, but so will the combustion chamber. with minimal mods you can see a gain.like 4 jaw said its a must to use the special spacer washers, or at least the hardened washers.

[Irelands child]

Not much of, if any gain. Additionally, some of the 351 heads were even more restrictive without removing the flow bump in the exhaust port. Then there is the potential of loss of Hp with additional combustion chamber volume. You do have to use the correct intake manifold gasket plus bushings to size down the head bolt holes from 1/2" to 7/16" (Summit offer them for $30- $50 depending on the brand)

Dave W

[kleen56]

Thanks for the great info. I was looking for a set of 69-70 351W heads. I heard about grinding the exhaust hump in the port and was planning on doing that. I met a guy who had a 302 w/ 351W heads on his 86 Mustang. That engine would run circles around mine and keep up with most BB. Don't know what he did, but it was on strong running 302. I currently have stock 289 heads, so the engine is need of something. I may go with the aluminum AFR heads or Pro Comp instead. They are more costly though. That's why I was looking at the 351W heads instead. Thanks again for the great info everyone.

[ScoTFrenzel]

Depends on what you have.
most every 289 heads are 54 cc, except '68. with 124 cc ports.
W heads are 61 cc, but slightly bigger valves and 144 cc ports (if they have the big spark plugs. Small plug heads are same as 302.)
Depends on piston dish, too, Ford juggled pistons to change compression in the 60s.
Later model 302 and 5.0 have 60-61 cc heads already and better pistons, but still small valves and small 289 sized ports.
Various years have the smog bump in the port that needs to be ground out.

W heads on a 289 used to be the hot ticket in the 70s, except the compression dropped to 8.0 with the stock pistons.

GT40 heads are the same as the 69-74 W head, but with different rocker arms and small spark plugs.

Big valve & ported 289 heads work well, but will cost several hundred dollars.

69-70 W heads sell for $25 each here. Few takers.

IMO 69-70 144 cc port heads are barely big enough to feed a 289.

[kleen56]

Originally Posted by ScoTFrenzel

Depends on what you have.
most every 289 heads are 54 cc, except '68. with 124 cc ports.
W heads are 61 cc, but slightly bigger valves and 144 cc ports (if they have the big spark plugs. Small plug heads are same as 302.)
Depends on piston dish, too, Ford juggled pistons to change compression in the 60s.
Later model 302 and 5.0 have 60-61 cc heads already and better pistons, but still small valves and small 289 sized ports.
Various years have the smog bump in the port that needs to be ground out.

W heads on a 289 used to be the hot ticket in the 70s, except the compression dropped to 8.0 with the stock pistons.

GT40 heads are the same as the 69-74 W head, but with different rocker arms and small spark plugs.

Big valve & ported 289 heads work well, but will cost several hundred dollars.

69-70 W heads sell for $25 each here. Few takers.

IMO 69-70 144 cc port heads are barely big enough to feed a 289.

It appears the most of you don't care for the 351W switch on heads? Interesting? The info makes sense. I know my pistons are the flat top, I have no idea on the compression ratio. If you had a 289, what heads what your recommend I go with?

[4 Jaw Chuck]

If I were you I would put some bigger valves in the 289 heads and port those, any head you buy (except new) will likely need a rebuild anyway why not do the ones you have?

Those 289 heads have nice small chambers so your CR will stay up where you want it. Lots of meat in those ports for getting in there with a grinder and you could do them the way they should be done.

Of course a brand new set is a pretty sweet deal too.

[ScoTFrenzel]

Originally Posted by kleen56

It appears the most of you don't care for the 351W switch on heads? Interesting? The info makes sense. I know my pistons are the flat top, I have no idea on the compression ratio. If you had a 289, what heads what your recommend I go with?

If you have true flat top pistons with valve reliefs, then you could use the early W head. Your compression would be in the 9s.
You could also get the .025 copper head gasket for better quench if you pistons are still below the deck surface.

Remember the 289 heads have 124 cc ports, and the W has 144 cc ports. Most 289 heads when moderately ported only get to 134.

You have to ask yourself= How much money do you want to spend to get heads with bigger stainless valves and full porting.

If you are friends with a machine shop that does circle track engines, you might get a set of 1.94/1.6 Chevy valves that are being pulled out of a used engine for free.
1.94/ 1.5 stock factory valves or used race 1.6 stainless exhaust make a good cheap conversion. Of course, new budget valves are less than $100 per set. Either way you will need new hard exhaust seats installed.
If you stick these in the W heads, milled for compression, you will be ok.
Then all you need is a good head man to do the work for free.