Bassman/NZ
Well-known member
So it's bullsh*t then...
Hollow vs Solid Lifters
- Thread starter BILL WZOREK
- Start date
Bruce Lancaster
Member Emeritus
Mild Flatheads seem to me to have plenty of control of the valve functions even with stock springs, stockers running out of steam beyond 4,000 and mild rods at maybe 5,000...
I have only encountered valve float on a single flathead, a stock 59A in a friends pickup truck, that must have floated at like 2,500 or 3,000! My guess is that the engine had been violently overheated and the springs cooked...it would float valves in entirely normal acceleration, and I once almost lost a drag race across an intersection to a VOLVO of all things because I had to short shift so much...I think only maniacs like Pete need to worry about weight in flathead valve trains!
I have only encountered valve float on a single flathead, a stock 59A in a friends pickup truck, that must have floated at like 2,500 or 3,000! My guess is that the engine had been violently overheated and the springs cooked...it would float valves in entirely normal acceleration, and I once almost lost a drag race across an intersection to a VOLVO of all things because I had to short shift so much...I think only maniacs like Pete need to worry about weight in flathead valve trains!
Pete
BANNED
Just for the fun of it . Sorry I do not know the brands .They are the same length
2 3/4 oz for the hollow
4 oz for the solid
And a stock steel lifter weighs 1.55 ounces.
Bruce Lancaster
Member Emeritus
I've posted a bunch of lists of flathead patent info on here in the past. One of the valvetrain drawings shows an otherwise production valve setup with a bucket lifter...meaning that the extra-long valve went to the BOTTOM of a lidless lifter. They provided slots like stock to let out the oil to reap the full lightening effect, and I wonder about the trade-off between extra valve weight versus lessened lifter weight. At any rate, Ford did not like to see any wasted weight in anything...
Have a look: http://www.google.com/patents/US1998612?pg=PA3&dq=valve+spring+inassignee:Ford+inassignee:motor&hl=en&sa=X&ei=AcuaUMadN6W80AHxjYG4Bg&ved=0CDcQ6AEwAA#v=onepage&q=valve%20spring%20inassignee%3AFord%20inassignee%3Amotor&f=false
or just look up patent # 1998612
They discuss weight benefits as either allowing higher operatting speed OR allowing lighter spring pressure...so they were presumably seeing benefits that would interest hotrodders, not just saved metal.
Have a look: http://www.google.com/patents/US1998612?pg=PA3&dq=valve+spring+inassignee:Ford+inassignee:motor&hl=en&sa=X&ei=AcuaUMadN6W80AHxjYG4Bg&ved=0CDcQ6AEwAA#v=onepage&q=valve%20spring%20inassignee%3AFord%20inassignee%3Amotor&f=false
or just look up patent # 1998612
They discuss weight benefits as either allowing higher operatting speed OR allowing lighter spring pressure...so they were presumably seeing benefits that would interest hotrodders, not just saved metal.
Last edited:
Bruce Lancaster
Member Emeritus
Hmmm..I think their real thinking emerges in the text: Lighter tappet allows reduce spring pressure, resulting in 2.3 more HP in the '33 engine from combination of reduced effort against spring and reduced friction. I think the increased RPM line is silly in this context, as I think on any stock flathead the valve train is easily capable of revving past the point at which the engine can make power.n The text is very interesting reading for flathead fans!
