28* initial timing for a 318? How can that be?

92b said

How would you test that? How much longer would a rod have to be to see a difference? How much of a difference would it be? I think engine masters did a rod length test. I can't remember if they swept the timing on both rods to see if there was a difference in optimal timing. Anybody else remember or have a link?

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The only way I can think of is you’d need to start with an engine like a SBC so you can get parts easier.

Then you’d need to start with a short rod, like 5.65 or whatever the 400rod length was (I’m sure that’s close but it may not be exact) and then test it against a 5.7, 5.85, 6.00 and 6.25 rod.

But…as you know none of that is in isolation. Changing the r/s ratio changes how the engine pulls fuel and burns it so that’s probably not very accurate anyway.

What I do know is I built one 5.65 rod 400 for a circle track deal back in 1996.

That engine always took way more timing than I thought it should have.

The owner of it was scared to death of an engine that wanted at least 42 total so he took it to a dyno that was about 5 hours from us and flogged it for two days.

He came back and said it was a waste of two days because the timing was what it was.