[RAIVJUMB]

Putting together the 74 SD motor (auto non air 3.42s) Auto has a shift kit in it from long ago so I left it. I am next trying to figure out cam and converter for this. The bottom end is going to be balanced, with bushed SD rods and forged pistons that will yield basically stock compression and the heads are redone but also basically stock. I am looking to be from somewhere around stock behavior to a bit higher like the original 310HP plan from Pontiac. I have a stock used cam but I think reusing it despite it having low miles is asking for trouble.

[73T/A]

Originally Posted by RAIVJUMB

Putting together the 74 SD motor (auto non air 3.42s) Auto has a shift kit in it from long ago so I left it. I am next trying to figure out cam and converter for this. The bottom end is going to be balanced, with bushed SD rods and forged pistons that will yield basically stock compression and the heads are redone but also basically stock. I am looking to be from somewhere around stock behavior to a bit higher like the original 310HP plan from Pontiac. I have a stock used cam but I think reusing it despite it having low miles is asking for trouble.

The original planned 310HP was achieved using the Ram Air IV (041) camshaft.Melling still carries it SPC-8 camshaft.

[RAIVJUMB]

I have contemplated going with a cam with the normal size gear and changing the distributor gear. Is there anything available with the sd size gear. Thoughts on something like a 744 type cam? Something with more duration was suggested.

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[73T/A]

Originally Posted by RAIVJUMB

I have contemplated going with a cam with the normal size gear and changing the distributor gear. Is there anything available with the sd size gear. Thoughts on something like a 744 type cam? Something with more duration was suggested.

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I overlooked the distributor gear issue.I am not sure what is available with the factory SD size gear.As far as the 744 cam,your current camshaft in your SD if stock would have the same duration and lift.The 041 cam will have more duration and more lift than the 744 cam.

[johnta1]

I'd go more lift and duration, the SD heads will love it.





Also use the normal cam gear setup as you said. Save the big dist. gear for later in case going back to stock setup.


I used a roller cam like HO Racing used in their SS car. LOTS of power.
But a bigger cam than stock will make some power.
Converter would depend on your rpm range and want the engine makes.