The Ford Barn - View Single Post - Proper Valve springs for 296 cu.in. flathead with Howard cam M12

Bored&Stroked · 02-05-2024, 01:53 PM

Isky 185-G springs - and I agree with Pete on the max spring pressure on the seat. You must ensure that you know the installed height to get to 75 lbs. The double spring setup that Isky used to sell was a complete waste of time - they actually perform WORSE than the 185-G springs.

I have a big custom roller cam and my seat pressure is 100 lbs on the seat. With 1.72" intake valves (heavier than 1.6" valves), I've never floated them - even at 6200 RPM.

02-05-2024, 01:53 PM	#9
Bored&Stroked Senior Member Join Date: Jan 2011 Location: Central Ohio Posts: 5,164	Re: Proper Valve springs for 296 cu.in. flathead with Howard cam M12 Isky 185-G springs - and I agree with Pete on the max spring pressure on the seat. You must ensure that you know the installed height to get to 75 lbs. The double spring setup that Isky used to sell was a complete waste of time - they actually perform WORSE than the 185-G springs. I have a big custom roller cam and my seat pressure is 100 lbs on the seat. With 1.72" intake valves (heavier than 1.6" valves), I've never floated them - even at 6200 RPM.