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Can someone provide OEM cam specs?

Posted: Thu Feb 15, 2024 10:18 pm
by Syscrush
Hey all. I've seen the lift info for the different years of intake and exhaust cams, but I'm having trouble coming up with the following specs (needed for both intake and exhaust):
  1. Duration (advertised or @1mm or @0.050")
  2. Lobe centerline
  3. Open and close time in crank degrees
Is this documented somewhere? Any info or pointers would be much appreciated.

Re: Can someone provide OEM cam specs?

Posted: Fri Feb 16, 2024 3:28 am
by bobcat
Phil, if I was at home I could send you all that but I don't have it here on this computer.
Surely someone on this site has it. IMO the best cams to use are 81-82. Better yet degreed
to 103in.- 105ex.

Re: Can someone provide OEM cam specs?

Posted: Fri Feb 16, 2024 3:57 pm
by Syscrush
Thanks a lot, Bob.

I'm not actually concerned with comparing or finding the best - I'm trying to find the necessary parameters to put into some modeling software to get some insight about my awful midrange. I'm pretty sure it's due to the very short primaries and the 6-2-1 design of the pipe, but some analysis would help to confirm or deny that hunch.

Re: Can someone provide OEM cam specs?

Posted: Fri Feb 16, 2024 5:30 pm
by Jeff Bennetts
From my notes, the specs should be here in the forum somewhere, search and verify, this is all I have.

'79 Lobe Height
Intake - 37.30mm-37.46mm
Exhaust - 37.50mm-37.66mm

'80 Lobe Height
Intake - 36.80mm - 37.06mm
Exhaust - 37.00mm - 37.16mm

'81-'82 Lobe Height
Intake - 37.00mm - 37.16mm
Exhaust - 37.50mm - 37.66mm

Re: Can someone provide OEM cam specs?

Posted: Fri Feb 16, 2024 6:12 pm
by Syscrush
Thanks, Jeff. Any ideas on how/where to find the duration and timing info?

Re: Can someone provide OEM cam specs?

Posted: Fri Feb 16, 2024 7:37 pm
by JoeInTUS
Is this what you are looking for? Shop manual chapter 1.
IMG_0301.jpeg

Re: Can someone provide OEM cam specs?

Posted: Mon Feb 19, 2024 1:46 pm
by Syscrush
That looks great, thanks!

So, if I understand correctly, duration @1mm lift would be:

5+180+40 = 225 degrees intake
40+180+5 = 225 degrees exhaust

Is that right?