what is the differance between 2bbl heads and 4bbl heads on a 302? i was curious because the 302 in my old truck had 4v heads out of a 72 f 150 but the heads were cracked so i took heads out of a 76 f-150 but they were only 2v heads is there a difference?

 

There was nether an F150 nor a 4 bbl 302 72 Ford pickup. If you put up the head casting numbers of both sets, I'm sure someone can tell you if there is a difference.

 

302's installed in 1969/79 F100's & 1975/79 F150's were only available w/a 2V carb. Ditto 1969/74 E100/300's & 1973/77 Bronco's.

 

The 302 wasn't available in the Ford trucks until mid-year 1969. However, the 302 was available in the Mustangs mid-year 1968, when the 289 ended production.

Possibly someone installed a J-code Mustang 302 engine, or the heads from one, on the engine in your truck.

The J-code '68 Mustang came with a 4 bbl carburetor and intake. It also had heads with a "4V" cast in between the rocker arm stands. C8OE-A and C80E-F castings.

The only major difference between the 4V 302 head and a regular 2V head is the size of the combustion chambers. The 4V head had 53.5cc chambers. The 2V heads had 63cc chambers.

Heads

There are a lot better small-block aluminum heads available from the aftermarket --such as AFR (Air Flow Research) 185s.

As far as stock Ford production 5.0L (302) iron heads go, the 1997.5-2001 Explorer GT40P heads are about the best factory iron heads you can get. They are marginally better than the '93 Cobra GT40 3 bar heads.

This is a set of GT40P 4 bar heads that I have, --shown just after I got home from the wrecking yard with them. (Notice the (4) bars cast into the ends of the heads).



"P" cast into the corner of the head (right side of photo) just outside the valve cover flange.



GT40P casting in between the rocker arms.



Five.Oh Info : The Ultimate Ford GT40 and GT40P Cylinder Head FAQ