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Discussion Starter #1
What was the highest RPM Redline every put in a factory Pontiac hood tachometer and what engine was it used for?
 

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Discussion Starter #4
You were correct about the engine, it was the Sprint OHC 6 banger. It was installed in A-body (Tempests & LeMans) and F-body ( Firebirds). However your RPM guess was incorrect.
 

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Pro/cons of hood tach? I think they look cool, but hate the idea of cutting a hole in my roof. Also what about it bad weather do they go bad easy?
 

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Discussion Starter #8
6,500 is the correct answer. It was for the 1967 OHC Sprint 6-cyl having 230CI and 215HP. A HO 10.5 compression motor that had the highest HP to CI ratio of any Pontiac engine produced during the muscle car era. Pontiac realized very quickly that the redline was set too high and started using 5,500 redlines after only a few months of production. Pontiac also decided the tachometers were too large and reduced the size both length and height after only a few months of production as well.
 

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Discussion Starter #9
Pro/cons of hood tach? I think they look cool, but hate the idea of cutting a hole in my roof. Also what about it bad weather do they go bad easy?
Note: A hood tach should be mounted on the hood so you can see it from the driver's seat. I do not advise mounting it on the roof.:banghead:
 

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6,500 is the correct answer. It was for the 1967 OHC Sprint 6-cyl having 230CI and 215HP. A HO 10.5 compression motor that had the highest HP to CI ratio of any Pontiac engine produced during the muscle car era. Pontiac realized very quickly that the redline was set too high and started using 5,500 redlines after only a few months of production. Pontiac also decided the tachometers were too large and reduced the size both length and height after only a few months of production as well.
I guessed the correct replacement, I was not aware of the original 6500! Good to learn...


And the Firebird was Verdoro Green!
The Hood tach is best looking in Nightshade Green....and can run extra rpms without engine damage....
 

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6,500 is the correct answer. It was for the 1967 OHC Sprint 6-cyl having 230CI and 215HP. A HO 10.5 compression motor that had the highest HP to CI ratio of any Pontiac engine produced during the muscle car era. Pontiac realized very quickly that the redline was set too high and started using 5,500 redlines after only a few months of production. Pontiac also decided the tachometers were too large and reduced the size both length and height after only a few months of production as well.
Very interesting. I got my info from a magazine article on the OHC-6 and it stated that the engine would spin 6,500 RPM's. Did not know a tach was redlined to that limit. The OHC-6, H.O. version had the Q-jet and a split exhaust manifold to create dual exhaust. The bottom end was pretty beefy for high RPM use as it had 7 main bearings, but the sides of the block were extended past the crank centerline and the main caps were cross-bolted on the sides by cap screws. The article stated that Pontiac hinted that outputs of 300HP and up were obtained in their lab.

Not a bad HP rating for '67 as that is better than 1967 Chevy 250CI 155HP, 2 bbl 283CI @ 195HP, or 2 bbl 327CI @ 210HP.

Sure would like to see more of these around, but the OHC 6 usually gets pulled in favor of a V-8.
 

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If mounted on the roof, I recommend a sunfoof to be cut-in, so that you can poke your head up and read the RPM's. Awkward while racing, to be sure, but stylish, nonetheless.
Seriously, hood tachs look great in my opinion, but were prone to hood slamming, vibration, and moisture damage. They didn't hold up as well as the in-dash units. The new reproductions? I don't know....they haven't been around long enough to tell.
 
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