Hornet Domed Piston

Ol racer

FYI

Ive never seen 'Domed' Piston's for a Hornet 6 before.....The Set was made by Jahn's.....

Uncle Josh

Huh. Looks like they would raise the compression ratio a little and help with swirl and scavenging. Anybody used any yet?

Ol racer

These Pistons came with a couple Hornet motors that I just picked up down State from a person that said his Dad raced modified's back in the '60's. They were used but cleaned this one up to picture....

Geoff

I can't see how this could have been used in Hudson motor. Either the compression height has been greatly lowered, or a large cut-out made in the cylinder head for the protrusion to fit into. There is just no room for such a dome to fit inside the ordinary compression space.

50C8DAN

If you review any of Jack Clifford's articles he states clearly that domed pistons in a flathead are a bad idea as they do not let complete combustion occur. I would need to look up his exact comments but he was never an advocate of this type of piston.

Ol racer

I dont think the motor could have breathed at all without major head rework. The guy said his dad won a lot of races, but these pistons must have been an experiment then used for short time because they appear in good shape.

Frankvintagefullflowcom

Not exactly what I'd call "domed" but apparently an attempt to fill the combustion chamber void created by the raised portion of the head, thus increasing C/R. Although an interesting approach, I'd guess that it might get in the way of a clean flow path for gasses, both in and out.
Ya can't blame 'em for giving it a try.....I've considered it myself. I'd agree that it was likely an experiment that didn't produce the desired results.
I think Geoff may be envisioning it in reverse to the actual installed position....but I'll bet he's realized that long before now.
F