Pontiac engines are ideal for boats. The air gap between the intake manifold and valley cover is perfect for putting a chain through it to use it for an ANCHOR.
I have a question for you I have a set of Pontiac heads that ND Center of where you are talkin about the casting number is a number 12 and I've also a buddy of mine's got to set it says 13's on it also has a set that said sixteens just wondering if you could please explain to me what the number 12 head was on and I was told that the number 12 head was a very good head for Pontiac
The number 12 heads are a 1970 400 high compression 2.11 1.77 valve head with 72 cc chambers. They are commonly referred to as a RA3 head and did indeed come on all RA3 engines in 1970 both automatic and manual transmission. They were installed on the 1970 RA3 400 engines, but they were also used on the 400 cu. in. 350 HP manual transmission cars too. As a side note, the number 13 heads have been incorrectly called RA3 heads. However they were not used on the RA3 engines as delivered from the factory. However they are identical in every way except for the casting number and probably the reason people call them RA3 heads. Since they were used on the automatic cars they did have a different rate valve spring compared to the number 12's.
Good info Don.
Thanks 👍
Good information Don.
Have a great day.
Thank U Sir 🙂 You as well !!!
That's the best "D" port head that you can find is the '67 670 head.
Many Pontiac enthusiast believe that. It is a good head no doubt :)
@@dcimotorsports1111
I agree. I had 4x and 6x heads.
Not that great . 2.11's and 1.66's with 96 cc chamber.
@@phillipthethird42 some of the aluminum aftermarket heads have 2.11 intake and 1,66 exhaust too.
The 670 heads are closed chamber . After 67 they are all open chamber. Is that correct?
Pontiac engines are ideal for boats. The air gap between the intake manifold and valley cover is perfect for putting a chain through it to use it for an ANCHOR.
I have a question for you I have a set of Pontiac heads that ND Center of where you are talkin about the casting number is a number 12 and I've also a buddy of mine's got to set it says 13's on it also has a set that said sixteens just wondering if you could please explain to me what the number 12 head was on and I was told that the number 12 head was a very good head for Pontiac
The number 12 heads are a 1970 400 high compression 2.11 1.77 valve head with 72 cc chambers. They are commonly referred to as a RA3 head and did indeed come on all RA3 engines in 1970 both automatic and manual transmission. They were installed on the 1970 RA3 400 engines, but they were also used on the 400 cu. in. 350 HP manual transmission cars too. As a side note, the number 13 heads have been incorrectly called RA3 heads. However they were not used on the RA3 engines as delivered from the factory. However they are identical in every way except for the casting number and probably the reason people call them RA3 heads. Since they were used on the automatic cars they did have a different rate valve spring compared to the number 12's.