Junkyard 5.9L Magnum + Edelbrock LA heads build

nm9stheham said

It is a matter of the relative temps at the start of combustion, the temps during combustion and the temps at the end of the power stroke. So if the absolute temps vary up or down, but the start, middle and end temps stay relatively the same, the pressures, torque and etc. will be the same.

FWIW: With your dimensional numbers, I am getting 8.9 SCR and 7.2 DCR at sea level (which is the difference I would expect with a cam with advertised intake duration of 274), with 6.2 effective DCR at 5000'. So, yes on the rear gears.....

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OK sounds about right, I didn't understand the "boost compression" on the Wallace Racing calculator but I realized it does mean corrected for altitude so I got the same numbers you did. BUT let's try something else... so a bone-stock 5.9L Magnum is rated at 8.8 SCR and with a stock cam having 62 ABDC intake closing (according to online sources), DCR at 5000' elevation is 6.19. And I know for a fact that even at this altitude a stock 5.9 Magnum has boatloads of bottom-end torque right off idle. SOO if my DCR is essentially the same as a bone-stock 5.9 truck engine I'm thinking the low-end torque should be adequate.

Shoot, maybe that's what Jim was shooting for with my cam? Trying to get the DCR the same as a stock engine? Smart, if that's true...