[Doug]

What year is cover #9790347?

Will it work for a 66 tripower setup on a later engine?

What years of covers work with a 66 tripower setup on later engines?

Thanks!

[Tom Vaught]

What you need to do is look for the "clearance divit" (cut-out area) on the timing cover that clears the front mounted Water Neck used on the Tri-Power engines. If the cover has no "divit", most 11 bolt covers do not), then you need to mod the cover to create one: (weld on the back side of the cover and machining on the side where the water neck housing will be).

In some cases the water neck can be ground on to "split the difference" on the amount of material that needs to be removed and you can eliminate the welding deal.

Another way is to have the cross-over on the manifold removed from the Tri-Power manifold, the surface that the waterneck/gasket mounts to cut to remove some material, (thermostat cut-out also deepened) and again no welding. Hope this helps.

Tom V.

[Kenth]

Timing cover #9790347 is from a 1968 engine using the "old" 8-bolt cooling pump and the "new" 1968 and later damper. No problem using this with any Tripower intake.
I have found that any cover up to at least 1974 units will fit the Tripower intakes.

Matching alternator, power steering pump brackets and pulleys is a different story.
I recommend using these parts that comes with the car.

[Tom Vaught]

Kenth is correct, I need to modify my statement I posted above.

Posted Earlier: "If the cover has no "divit", most 11 bolt covers do not), then you need to mod the cover to create one: (weld on the back side of the cover and machining on the side where the water neck housing will be)."

1) Any TRUE FACTORY 11 BOLT Cover will have the "Divit" in the cover that will allow using a Tri-power waterneck once the WP bolt boss is modded.

2) The 301 FACTORY Timing Covers do not have the 'Divit" (it would have to be added)

3) The 69 - 76 "11 Bolt Covers" have a long "bolt boss" added to the Pontiac Timing Cover right where the Tri-Power water neck wants to go into the "divit" but the bolt boss interferes with the Water Neck and needs to be shortened about 1/4" on the 'waterneck side' to get the clearance you need to let the waterneck FIT into the "Divit". Otherwise you would say "the parts do not fit".
BUT THEY WILL FIT WITH THE BOLT BOSS TRIMMED.

4) The Pioneer Timing Covers say they fit a 69-UP 11 Bolt water Pump and they do but they were not exact duplicates of the 69-76 cover and do not have the "Divit" A Divit may need to be added and bolt boss trimmed.

5) Most of the Offshore Timing Covers for the 11 Bolt Cover are made wrong for the Tri-Power Installation (Waterneck).

Sorry for the confusion, needed to add more detail.

Tom V.

[Doug]

Tom,

So is it correct that to use a 66 tri-power manifold on an engine with a stock 1971 timing cover, the ONLY thing you have to do is cut off about 1/4" of the bolt boss to make clearance??

Also, if such an install is made, is it possible to remove the waterneck and change the thermostat without having to remove the manifold (or timing cover)?

Thanks for all info!

[b-man]

Originally Posted by Doug

Tom,

So is it correct that to use a 66 tri-power manifold on an engine with a stock 1971 timing cover, the ONLY thing you have to do is cut off about 1/4" of the bolt boss to make clearance??

Also, if such an install is made, is it possible to remove the waterneck and change the thermostat without having to remove the manifold (or timing cover)?

Thanks for all info!

Yes and yes.

Used a '74 cover with a '66 tri-power and trimmed the boss about one eighth of an inch, water neck was still easily removed but clearance was tight.

[Doug]

Thanks to all!

I'm selling a 66 tri-power setup to someone with a 71 455 and I wanted to make sure his stuff will work without too much work.