[b-man]

Put ‘65-‘66 rockers on it that have the spurt hole in the pushrod socket and you’re good.

This way you’ll be bypassing the stud oiling (that you’re not getting anyway because of the cam) and using the superior pushrod oiling of the rockers like on high-performance 1964 engines and subsequently all 1965 and later engines.

Early Super Duty engines also had pushrod oiled rockers.

[JJ88]

Thanks so much. This was the thought my mechanic had just wanted to verify with some knowledgeable Pontiac people. Really appreciate the quick response. Thanks again!

[JJ88]

Originally Posted by b-man

Put ‘65-‘66 rockers on it that have the spurt hole in the pushrod socket and you’re good.

This way you’ll be bypassing the stud oiling (that you’re not getting anyway because of the cam) and using the superior pushrod oiling of the rockers like on high-performance 1964 engines and subsequently all 1965 and later engines.

Early Super Duty engines also had pushrod oiled rockers.

Hi B-man
One more question. So I will be basically be upgrading my 1964 - 389 to be like a 1965 - 389 correct. The push rods existing measure at 8.6875

What I am finding for 65/66 - 389’s the push rods measure 8.686 a difference of 0.0015.
Does this sound right to you and would they be .0015 shorter due to the oil spurt rockers possible being slightly thicker. This is a stock motor.

[JJ88]

Originally Posted by JJ88

Hi B-man
One more question. So I will be basically be upgrading my 1964 - 389 to be like a 1965 - 389 correct. The push rods existing measure at 8.6875

What I am finding for 65/66 - 389’s the push rods measure 8.686 a difference of 0.0015.
Does this sound right to you and would they be .0015 shorter due to the oil spurt rockers possible being slightly thicker. This is a stock motor.

Also wondering if you have any recommendations on what rockers I should purchase and from where. 7/16 bottle style with 3/8 threads

[steve25]

The first order of business is to inspect all 16 of your rocker studs.

Remove all the rockers and balls and look for gouges and ware spots where the balls ride.

Sometimes it's difficult to get the rockers off because the balls are hung up in a ware groove.

Seeing as your motor is a 64 they may be worn and if worn enough you will never have a quite valvetrain even with new parts.

[b-man]

Originally Posted by JJ88

Hi B-man
One more question. So I will be basically be upgrading my 1964 - 389 to be like a 1965 - 389 correct. The push rods existing measure at 8.6875

What I am finding for 65/66 - 389’s the push rods measure 8.686 a difference of 0.0015.
Does this sound right to you and would they be .0015 shorter due to the oil spurt rockers possible being slightly thicker. This is a stock motor.

One and a half thousandths is immaterial. Even 15 or 20 thou means nothing here. Depending on where you find that pushrod length listed the number seems to vary a little depending on the source.

Here in this post a little further down you’ll see how we determined the correct pushrod length for my 1964 421, 8.670” which is essentially stock length:
https://forums.maxperformanceinc.com...2&postcount=75

Originally Posted by JJ88

Also wondering if you have any recommendations on what rockers I should purchase and from where. 7/16 bottle style with 3/8 threads

Finding those later 326 / 389 /421 rockers new may be difficult to impossible. They’re slightly different than the later rockers geometry-wise.

Perhaps look at sourcing a good used set where someone has properly kept the individual rocker pivot balls paired with the individual rockers they were originally used with.