performance · FF-0418

What will set the RPM limit for the ARDUN engine on the dyno?

The valve train. Steve expects peak power closer to 6,000 RPM, higher than the roughly 5,700 the earlier Flathead was run to. He is not worried about the bottom end. His concern is the complicated valve train: the push rods are long and slender at 5/16, and the valve springs are not very heavy. Whatever upper limit he sets for the test will come from what he and others who have run these engines think the valve train can take.

Expert

Steve Coppock

Evidence

expert attributed

Component

RPM limit and valve train

Applicable scope

Steve Coppock's supercharged ARDUN overhead valve Flathead, mocked up before its dyno test