[Joe37]

Does any one have any documentation on what cars got the vacuum systems and what got the mechanical systems? I have seen original big cars with manual transmissions and vacuum tri-power. Never really paid any attention to GTO's with automatics but don't recall seeing any vacuum systems on the GTO's.

[65 Lamnas]

Originally Posted by Joe37

Does any one have any documentation on what cars got the vacuum systems and what got the mechanical systems? I have seen original big cars with manual transmissions and vacuum tri-power. Never really paid any attention to GTO's with automatics but don't recall seeing any vacuum systems on the GTO's.

IIRC, Pontiacs never used the vacuum operated on M/T cars after 1964....only the A/T cars in 65-66.

[Joe37]

Thats kind of what I figuring, my cousin has an untouched '64 GrandPrix with manual transmission and vacuum tri-power setting in his stash of cars.

So, all the mechanical sets prior to 1965 were dealer add-ons or aftermarket?

1965 and 1966 are the only sets with factory mechanical linkage?

What about a 1964 GTO with automatic?

[60sstuff]

The following are for the GTO series from the Factory.

1964 Tri-Power,
Manual shift and Automatic came with Vacuum linkage.

1965 Tri-Power,
Manual shift - Mechanical linkage. 19091 built.
Automatic - Vacuum linkage. 1456 built.

1966 Tri-Power,
Manual shift - Mechanical linkage. 15803 built.
Automatic - Vacuum linkage. 1759 built.

[Joe37]

Thanks for the information on the GTO's. Could one assume the '65-6 big cars were the same way?
Not that any of this matters really, just curious.

Joe

[Stuart]

1961 big cars with tripower were all vacuum operated from the factory, but a mechanical linkage was available over the counter.

[60sstuff]

Beautiful ‘66 Reef Turquoise 2+2 421 HO Survivor with it’s full vacuum linkage intact.

[Joe37]

Lets go with this,
1964 and older, all vacuum operated, manual or automatic transmissions
GTO, and big car

1965 - 1966, automatic transmissions , vacuum operated tripower
1965 - 1966, manual transmission, mechanical tripower

Mechanic linkage was available over the counter prior to 1965
Aftermarket kits also available

[60sstuff]

Originally Posted by Joe37

Lets go with this,
1964 and older, all vacuum operated, manual or automatic transmissions
GTO, and big car

1965 - 1966, automatic transmissions , vacuum operated tripower
1965 - 1966, manual transmission, mechanical tripower

Mechanic linkage was available over the counter prior to 1965
Aftermarket kits also available

That looks correct.

[60sstuff]

Joe,

Kickdown switch for Automatic transmission with Tri-Power.

BIG CAR, 65-66 had the switch located “under the hood”.
A bracket on the LH side of center carburetor held the automatic kickdown switch.

GTO, 1965 also had the switch located as above “under the hood” on LH side of center carb.

GTO, 1966 now had this transmission kickdown switch located “inside” above the accelerator pedal.

A few on this site haven’t figured this out yet.

[Rich-Tripower]

What's the best thing about the vacuum actuated tripower system? You can remove all the vacuum stuff and replace it with a simple mechanical system! Even the most beautifully restored vacuum system looks better sitting in a box on a shelf than on a car in my opinion. We have all the parts to the vacuum system for our 64 GTO but it has never been on the car in my memory. The temp switch is seized anyway. Even Pontiac sold mechanical replacements through the parts department back in the day. Why they ever had a vacuum system in the first place is beyond me.

[bill ryder]

Those are great pictures, Chris!!!

"Bill"!

[60sstuff]

Originally Posted by Rich-Tripower

What's the best thing about the vacuum actuated tripower system? You can remove all the vacuum stuff and replace it with a simple mechanical system! Even the most beautifully restored vacuum system looks better sitting in a box on a shelf than on a car in my opinion. Why they ever had a vacuum system in the first place is beyond me.

Opinions vary.

Some people like repainted cars with over the counter incorrect items.
These cars are “a-dime-a-dozen” at cars shows.

Me, and many others prefer the Original Factory Built cars that are few.

[Rich-Tripower]

Our car is hardly a painted-the-wrong-color modified car. But that vacuum system does not benefit the car.