[unruhjonny]

Originally Posted by JLBIII

On the 067 cam, I have a 68 Firebird with a 400HO, TH400 and ac. It is my understanding that the 067 was used in the 400HO with TH400 trans and the 068 was used in a 400HO with a manual trans.

interesting.

I don't recall reading (or noticing an instance of a drivetrain that would have had the 068 with a stick being changed to a 067 because of the automatic (ect).

[Kenth]

"068 was in all 1970 RAIII engines, as well as 71-72 455HO - and the same lobe profile and timing as the one used in 73-74 SD455 engines."

1973-74 455SD engines used the same lobe profile and timing as the 744 grind.
Was planned for the 041 cam but did not pass emission test.

FWIW

[unruhjonny]

Originally Posted by Kenth

"068 was in all 1970 RAIII engines, as well as 71-72 455HO - and the same lobe profile and timing as the one used in 73-74 SD455 engines."

1973-74 455SD engines used the same lobe profile and timing as the 744 grind.
Was planned for the 041 cam but did not pass emission test.

FWIW

really - well then I have some egg on my face!
I thought (going off memory) that the original intended SD455 cam profile was the 744, but that failed emission, and it was downgraded to the 068.

Thank you for the correction.

[scott70]

Originally Posted by unruhjonny

interesting.

I don't recall reading (or noticing an instance of a drivetrain that would have had the 068 with a stick being changed to a 067 because of the automatic (ect).

I know the 70 gto 455 came with the 068 cam with a manual trans and the 067 with the thm400. Only diffrerence between the different cams was the transmission choice.

[Formulajones]

Originally Posted by scott70

I know the 70 gto 455 came with the 068 cam with a manual trans and the 067 with the thm400. Only diffrerence between the different cams was the transmission choice.

Kind of interesting how they did that in a 455, yet the RAIII 400 engine of 1970 just came with the 068 cam no matter what trans you chose. Considering the 068 would act much bigger in a 400 and wouldn't even put a dent in a 455.

[PAUL K]

Originally Posted by Formulajones

Kind of interesting how they did that in a 455, yet the RAIII 400 engine of 1970 just came with the 068 cam no matter what trans you chose. Considering the 068 would act much bigger in a 400 and wouldn't even put a dent in a 455.

Pontiac did away with 744 cam in mid 1969 I believe. They were having complaints about cold start rough idle in Northern climates. Before that the four speed cars with 48 heads came with the 744 cam (and stiff valve springs) and automatics got the 068.

[scott70]

Originally Posted by Formulajones

Kind of interesting how they did that in a 455, yet the RAIII 400 engine of 1970 just came with the 068 cam no matter what trans you chose. Considering the 068 would act much bigger in a 400 and wouldn't even put a dent in a 455.

Yes,,,when I bought my GTO the motor had never been touched internally. Still had the 068 'S" cam and nylon covered timing chain. With that cam it idled like a kitten but had a good low rpm pull. Now a RA4 sized cam with Rhoads and its only a little choppy,,,still pretty smooth.