Which heads are beter?
 

Im just getting started in engine building and working on a budget.I have a rebuilt 351W short block with a very mild cam and stock type pistons. I have early model 351W heads with the slightly larger valves or 289 heads(casting# 5C15).This is where I get lost. Do the 289 heads have a smaller combustion chamber and does that make for better performance than the larger valve/combustion chamber 351W heads on the 351W? How would the 289 do on a 302 with a mild cam? The most I would like to spend on heads is the price of a good rework with hardend seats so porting and extreme mods are out. Does any have the specs on these 289 heads( what year and cc size) and cc size for the 351W heads (casting DOOE) Thanks in advance. The completed engine is going in my 66 Mustang!!!!

I think the 289 had a 54cc, the 302 had a 59cc and the 351 was 64cc. I don't know what you think the cost of a good rebuild will be, but I had some 302 heads done about 9 months ago, new seats, hot tank and mag, new valves (1.94x1.60 Chevy's) new guides, and I think it was aruond $500.00 material & labor. You might consider Power Heads in Ca. They work on the exchange program. You get precision CNC ported, 1.94x1.60 SS valves, Chrome moly retainers, .550 lift springs, screw in studs and guide plates(you could lower the cost by eliminating these and reusing your own rockers and push rods), hardened seats, and solid bronze guides. With the screw in studs and guide plates they go for 675.00 complete, and you send them your old heads. Maybe without the studs and plates $600.00. I have all the flow data if your interested.

Ron

With today's pump gas, I think you're better off with 351W heads about 1969 vintage. You won't want more than about 9.5 CR. The 351W heads will breathe better than the 289 heads.
When you get them rebuilt also get them pocket ported and milled some. Make sure the heads you get have 1.85/1.54 valves. In a mild engine, this should be all you'll need. I'd use CC Magnum roller tip rockers for a street type engine. I think you can get all this for about $500. This is the route I took a couple of years ago in my '66 with a 306 CI engine and got 285-300 HP. If you want the exact specs, e-mail me. I have drag strip data too, if you're interested.

Forgot to leave you the phone number for Power Heads. You might just call them order a catalog, and look at the flow numbers they have on the heads they offer. 714-992-4909 . In my humble opinion, its probably the best bang for the buck. I have no doubt that the machine shop cost, for what you get, will exceed the heads you can buy already assembled. I run TFS twisted wedge on my 306 coupe and Victor Jr.'s on a 306 FB. Also good heads, but a little spendy.

Ron