[Zooguy]

Okay I have 2 66 full size 4 door Pontiacs a starchy executive and Bonnie. My Star Chief Executive has the factory 389 but my wife's Bonneville has a 1970 400 short block with 1968 #15 400 heads.

I was wanting to know if the brackets that hold the A/C compressor and other accessories from my 389 will fit the 400 in the wifes car. My motor is coming out of my car and I didn't know if I could swap over the accessories or if it would be easier just to swap the entire engine.

[mysticmissle]

I haven’t tried it but as long as you keep the brackets together w the motor and maybe the water pump I believe it will work on either

[rolling money pits]

Someone smarter than I will opine I’m sure…

Like mentioned above, the WP height may be an issue.

Alt and PS brackets should be OK, since both sets of heads ( I assume ) are 70 or earlier.

[chiphead]

Assuming the 66 engine has a 66 balancer and timing cover, and the '70 engine has the '68-later balancer with 11 bolt pump and 1970 accessories, the answer is: The brackets will fit but pulleys won't line up. You'll need to swap over the timing cover and balancer from the 389 onto the 400 so the 389 accys all line up on the 400..

[Zooguy]

Originally Posted by chiphead

Assuming the 66 engine has a 66 balancer and timing cover, and the '70 engine has the '68-later balancer with 11 bolt pump and 1970 accessories, the answer is: The brackets will fit but pulleys won't line up. You'll need to swap over the timing cover and balancer from the 389 onto the 400 so the 389 accys all line up on the 400..

All right so that leads me to my next question is this because the 400 pulley sticks out too far or is it sucked in too much? I'm trying to understand the misalignment

[steve25]

The 389 heads do not have the needed bracket towers on the exh side of the heads like all 67 and up heads have.

[Schurkey]

396???

[Kenth]

Originally Posted by steve25

The 389 heads do not have the needed bracket towers on the exh side of the heads like all 67 and up heads have.

What 1967 heads have the needed bracket towers?

[chiphead]

The 1966 6-bolt balancer and crank pulley is designed to line up with the 8 bolt water pump pulley. The '69-70 4-bolt balancer and 11 bolt water pump stick out a different amount, and that's accounted for with the different height of the '69-70 crank and water pump pulleys.

I know the '67 accys and '67 accy pulleys will line up with the '69-70 standard height 11 bolt pump and balancer. You need to use the '69-70 WP and crank pullies.

Now that I think about it, you may be able to swap the '66 PS/Alt brackets, accys and accy pulleys onto the '70 engine, and re-use the '70 crank and water pump pullies, 4-bolt balancer and 11 bolt timing cover. The accy bolt holes in the heads are the same, and they just added a hole in '71.

If it still won't line up, you'll need to swap the 66 balancer and timing cover. Or use the '68 one-year only timing cover, use the 4 bolt balancer, the 69-70 crank pulley and the '67-68 water pump pulley. The '68 cover is one-year only, as it uses the 67-earlier 8 bolt pump but '68-later 4-bolt balancer.

The '71-later engines went to stamped brackets and again different pulleys than '65-66, 67, 68, or 69-70 setups. The confusion is because the brackets and pulleys changed every year in some fashion, between 1965 and 1971.

After '71, the engine accessory design team stopped taking hard drugs and the design stopped changing every year.

[chiphead]

Originally Posted by steve25

The 389 heads do not have the needed bracket towers on the exh side of the heads like all 67 and up heads have.

Do you mean for the AC compressor mounting brackets? There are small bolt bosses on the exhaust side of '67-later heads for the AC compressor. Are those not there on '66-earlier heads?

[steve25]

The 3 vertical bosses, 2 of which are seen between the spark plugs on these 68 heads are not present on the earlier heads.