[bradleyc309]

Hello all,

I have a 1964 B-Body 389 engine code 11H, I would like to freshening it up for pump gas. It has the 345 heads and I will be putting a 1965 Tri-Power on it.

Any recommendation?

[Tom Vaught]

Does your engine have a block mounted starter or bell-housing mount starter?

Tom V.

[Cardo]

It will most likely require you to change both the thermostat housing, and the oil filter housing. I just put a 1965 B body motor in my 1965 Lemans. You will need the angled oil filter housing not the 90 degree one.

[bradleyc309]

Tom,

It has the block mounted starter.

[b-man]

Fly in the ointment - a 1965 Tri-Power intake won’t bolt onto 1964 ‘345’ heads, a ‘64 Tri-Power intake must be used.

[bradleyc309]

I'm looking at getting either a 64 Tri-Power intake or 65 up heads.

[tom s]

I have a complete 64 tripower I just pulled from my 62 GP 389 if you have some interest PM me.Mike Wassen did the carbs,was running fine when the engine was pulled.I also have a compete 65 for sale on this site now.Tom

[b-man]

Originally Posted by bradleyc309

I'm looking at getting either a 64 Tri-Power intake or 65 up heads.

Best course of action would be to swap heads.

1964 - 1.88/1.60 valves. Rocker arms oil through the studs on all lower performance heads such as the ‘345’ heads. Only the high performance 9770716 heads (GTO 389, 421 HO, etc.) oiled through the pushrods and were equipped with 1.92/1.66 valves.

1965 - 1.92/1.66 valves. Rocker arms oil through the pushrods. Be sure to use 1965 - 1966 rockers with the spurt hole at the pushrod end unlike earlier rockers.

[Dick Boneske]

b-man is correct. If you already have a '65 Tripower setup, the 345 heads will not work. A set of casting #77 heads would be correct for a '65 GTO and bolt on to the '64 block with no mods. As has been pointed out, you need to be sure the rocker arms have holes at the pushrod location for oiling.

I believe you can find a set of #77 heads fairly easily and fairly inexpensively. The only issue I see is compression ratio. If the '64 block has flat-top pistons and you use #77 heads, compression ratio will be too high for today's pump gas. It's generally agreed that 9.5:1 is the highest we can go with cast iron Pontiac heads.

If you do decide to go with the 345 heads, I have several '64 Tripower intakes which would accept the '65 Tripower carbs needing only a change of choke heater tubes to the center carb. I would trade a '64 intake for your '65 intake if you decide to go that direction. The '65 intake is worth more than a '64, but we could work out details if you're interested.

[bradleyc309]

Dick,

do you still have any 1964 Tri-Power intakes with water neck?

[bradleyc309]

How to block a 1964 11h 389 oiling after adding 1965 and later heads?

[b-man]

Originally Posted by bradleyc309

How to block a 1964 11h 389 oiling after adding 1965 and later heads?

The head gasket will seal it, no worries.

[bradleyc309]

Thanks,

I was wondering if I installed 1972 7k3 heads if I need to do anything else.

[389]

I would stick with the closed chambered heads for a street ride.. Look for a set of 092. They have a slightly lower compression (10.5)and would only need to have screw in studs installed.. I'd use the 068 cam or the Summit 2801..

[bradleyc309]

Don't the 92 heads have screw in studs?

[b-man]

Originally Posted by bradleyc309

Don't the 92 heads have screw in studs?

No.

None of the 326/389/421 heads have screw in studs.

[389]

Did the 670 heads have screw in studs?

[b-man]

Originally Posted by 389

Did the 670 heads have screw in studs?

Absolutely yes.

First head to have them. The lower performance heads produced in ‘67 still had press in studs. The factory didn’t go exclusively screw-in until 1974, before that many lower performance heads retained their press in studs.

All 1966 and earlier heads had press in rocker studs, even the Super Duty heads did although they had the studs pinned to keep them from backing out.

[John V.]

b-man, the change occurred a bit before '74. Late '73 4X heads went exclusively to screw-in. Years ago after researching ad nauseum the '73 and '74 4X heads, we had more or less pinned down the changeover to screw-in based on head cast date. We also learned about the secondary stamp codes matched to application during that effort.

Only after spending hours figuring out when the switch was made, Rocky Rotella uncovered the factory documentation that would have saved hours of research.

The engineering change was justified on a cost savings, reduction of cast iron IIRC. I suspect that was a trumped up justification but resulted in the use of the superior screw-ins. April/May time frame is roughly what I remember.

If memory serves, the late John Sawruk may have been the guy who wrote up the change document. I have a copy of the doc around somewhere. I'm sure Rocky remembers it better. I teased him at the time that we could have saved a lot of time if he had uncovered the doc a lot sooner.

Isn't all that significant to this discussion but figured I'd mention it at least for historical accuracy.

I'm in way over my head to comment on mixing and matching parts but I thought there was a possible issue with the use of the '72 7K3 heads and an early intake, perhaps something to do with the crossover or maybe a port mismatch?

Might also have issues with lacking holes for accessory bracketry and missing holes for exhaust manifolds. Not insurmountable. But the more you mix and match, the more you will struggle to make everything work.

[MarkS57]

Originally Posted by John V.

I thought there was a possible issue with the use of the '72 7K3 heads and an early intake, perhaps something to do with the crossover or maybe a port mismatch?

Might also have issues with lacking holes for accessory bracketry and missing holes for exhaust manifolds. Not insurmountable. But the more you mix and match, the more you will struggle to make everything work.

From what I understand there are intake gaskets out there that will address the crossover issue, I don't know how well they work though. Also the valve angles are different in the later heads so you have to be careful about valve lift. I don't think its an issue with something like an 068 cam with its ~ .406 lift; others may chime in. For later heads, unless you have the 7K3's, my $.02 would go to something like a 6X4's; either way, your compression will be significantly lower with those heads.

Cheers!

Mark