The Ford Barn

Henry Floored · 12-09-2017, 12:01 PM

Well gang EVERY Flathead block I have ever seen is factory relieved. That big eyebrow cast or machined into the deck around the valves is a flow relief.

If you wish smooth the edges and radius the top edge of the cylinder that is in between the head gasket. I doubt anything more would be of help though I've got no flow numbers to prove it either way.

The idea of the transfer area in a Flathead Ford is to turn the mixture down into the cylinder because the flow wants to go straight up.

This is the plight of any side valve engine.

Ford Flatheads are actually quite sophisticated in this area. Pull the head off any side valve lawnmower engine and you'll see what basic looks like.

The early racers had it right, (remember it took a while and a bunch more cubic inches for the OHV's to start beating the Flatheads on the salt) when they started "popping" the piston up into the head and greatly reducing the impediment to flow without giving up compression.

I can't think of one reason why even a street performance engine couldn't benefit from this other than extra cost.

12-09-2017, 12:01 PM	#25
Henry Floored Senior Member Join Date: May 2010 Location: Florida Posts: 630	Re: Building for Torque Porting Question Well gang EVERY Flathead block I have ever seen is factory relieved. That big eyebrow cast or machined into the deck around the valves is a flow relief. If you wish smooth the edges and radius the top edge of the cylinder that is in between the head gasket. I doubt anything more would be of help though I've got no flow numbers to prove it either way. The idea of the transfer area in a Flathead Ford is to turn the mixture down into the cylinder because the flow wants to go straight up. This is the plight of any side valve engine. Ford Flatheads are actually quite sophisticated in this area. Pull the head off any side valve lawnmower engine and you'll see what basic looks like. The early racers had it right, (remember it took a while and a bunch more cubic inches for the OHV's to start beating the Flatheads on the salt) when they started "popping" the piston up into the head and greatly reducing the impediment to flow without giving up compression. I can't think of one reason why even a street performance engine couldn't benefit from this other than extra cost.