Term Nailhead!!

Well, here goes!! Where did the term "nailhead" arise from?? I've been told it stemmed from the valves looking like nails but so do any valves & yes I know the upright design for the heads quite well. I put a 322 in a '40 ford in the '50's & have two 401's in massage mode currently but I'm ashamed to say I haven't a clue about the origin of the term "nailhead". Oh, oh I'll bet this post will generate an overload of mud thrown my way, but I have to know!!

As I understand it the term nailhead comes from the small exhaust valves. The look more like nails than most valves because they are small. I have also heard them referred to as nailvalve engines.<BR>Tomsriv<BR>71 riv

The nailhead term is from the vertical position of the valves. They stick up like nails hammered into a 2x4.<P>I think the exhaust valve size is way overblown. The restriction on the engine is primarily in the porting. If you look at the valve train, it is backwards. The pushrods actuate the rocker arms from the outboard. Conventional engines actuate the rocker arms from the inboard side. The result of the backwards design is all the hoops and loops in the porting. That is why these engines seem to run out of wind a little over 4000 RPM. <P>Next!!!

I have many magazines from the fifties....nailvalve is the term I have seen for years. <P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.<BR>"Fan of anything that moves human beings"