Originally Posted By fast68plymouth
In the last year, I know of three people who have had customers cars in their shops to address the exact same problem.

In those three cases, the cam had been installed advanced by 2.5 teeth.
They had the bottom gear key way straight up, dot on upper gear straight down........ instead of “dot to dot”, which will have the bottom key way parallel with the #1 cylinder(not straight up).
The cam installed key way to dot is advanced 35degrees.

It sounds like some kind of valvetrain issue to me........ cam timing, springs, lifter preload, etc.


I am trying to think through your post...

The Cam gear Dot was at 6 o'clock and the Crank gear dot was at 12 o'clock...however I don't recall where the crank key was pointed.

That said, the balancer aligns at 0° on the timing cover with the #1 piston is at TDC. I don't think I can be off by 2.5 teeth if I am dot-to-dot on the gears and #1 is at TDC along with the balancer reading...Right?

In addition, I should mention that the truck never really ran over 4,000rpm before the cam swap. I attributed it to the engine's era and the max power rating for the engine was around 3600-4000rpm when new anyway.

1972 Barracuda - 5.7L Hemi, T56 Magnum 6spd - https://www.facebook.com/GoodysGotaHemi
2020 RAM 1500
[img]https://i.imgur.com/v9yezP9.jpg[/img]