302 marine heads?

[craigc]

Is there something different when 302 heads are listed as marine heads? they all cool and flow the same right? I should be able to put " Marine heads on a motor for road application correct?

 

[spap]

I think it depends on the year,
I think in the early 70 s they sometimes used 351 heads the engines were usually 4 barrels with brass freeze plugs and bronze valve guides.
They will have a number on them under the valve cover,
Marines engines live a tough life but the heads should just bolt on

 

[Broncobowsher]

Performance wise, nothing special.
Often there might be minor changes to materials for corrosion reasons. Blocks will get brass freeze plugs instead of steel, stuff like that. Nothing that will matter on the road.

I've seen Broncos with boat motors before. Still had the OMC sticker on the valve cover. In the 80's the mustang performace team was wanting a better engine. I know some people who worked at Ford at the time. I remember hearing the story and the guy in the engine lab told them they were working way too hard at it. He handed them a cam and told them this is what you need to use. It was the marine 302 cam. They stuck it in the mustang 302 and the 5.0 HO was born. Still living life through a 2-barrel carburetor. The 80's HP wars were on and every year up to '87 there was something better for the HO motor. 4-barrel intake, roller cam, EFI, etc.

But where it started, with that marine cam, was just the regular boring 302 heads in both the car and marine applications.

 

[nickgp]

That’s interesting about the marine cam being used in the first 5.0 Mustangs. I bought a brand new 82 GT. Even with a two barrel carb, it blew the doors off of new Z 28s, Trans ams and several so called muscle cars. Everyone wanted to race me. I picked and chose carefully who I would run. Only race I lost was to a Mazda RX 2. Little did I know, the sum bitch came w a Wankle rotary engine.

 

[jckkys]

The best info I can find says that marine engines used Mustang heads through 1990 when Ford started using the 2 bar GT40 heads that had 69cc chambers for both 302s and 351s. In '91/'92 they used the 3 bar GT40s with 65cc chambers. '93 used the 3 bar with 62cc. That's all I can find in an article on GT40 heads.

 

[craigc]

so these are A4B D50E 302 heads I think that would be 1975 ( D5)? any more info available?

 

[Broncobowsher]

Same as any other '75 302 head.

 

[jckkys]

Tom Monroe's book How To Rebuild Your Small-Block Ford describes the '75 302 heads as having 58.2cc chambers with 1.78"I and 1.45"E valve diameters. In this case the marine heads aren't different from the car/truck heads.