Why are the heads so over-bolted?
The Ford Flathead is a low-compression engine (5.5-7.2/1)…there are hi-comp turbodiesels out there with less bolts clamping down.
IIRC they went to 24 studs when they began offering aluminum cylinder heads.
the flathead v8 had very poor cooling and hilariously uneven heating thanks to the exhaust ports having to be routed from the inboard side of the cylinder to the outboard. Adding more head studs improved the clamping stability and head gasket life.
basically they did it because it was crudely designed and manufactured (by modern standards) and that was the easiest solution.
Sort of agree with JZ. As an engineer in a previous life, it drives me insane to see anything over-engineered because of laziness or lawyers/insurance. Unless someone provides compelling evidence to the contrary, I’m going with over engineered.
dude. it came out in 1932. they didn’t have the tools and knowledge we have today. it was amongst the first monobloc V8s in existence.
heck, what we have today is still light years better than what we had even in 1970 (almost 40 years after the flathead was released.) Today we have a 302 cubic inch V8 which makes 460 horsepower, idles smooth as silk, and is gentle enough to be a daily driver. In 1970, a 302 cubic inch V8 made ~300 horsepower and was a shaky, chattering mess. if you could get an engine of that size up to 460 horsepower, it simply would not idle.
My WAG was going to be based on the poor state of metallurgy.
Uneven heating due to exhaust transit sounds very good as well.
Bolts are cheap, over engineered makes tons of sense too.
While that may be somewhat true, now we make that 302 put out 1300 horsepower
and shake rattle roll
if you do, no one drives it on the street.
I think the major reason for the large # of bolts compared to a modern engine is that all modern engines are overhead valve and/or over cam. The flathead was just that a flat head and had comparitively little beam strength or torsional rigidity compared to a modern head. The engineers of the '30’s were perfectly capable of calculating these values. Using standard handbook values for what size, how many, spaced how far apart they should be plus of course a suitable safety factor.
In addition to all the above, the nature of a flathead is that you have a much larger pressure area as compared to an OHV system; probably around twice the raw cylinder area. So in terms of total force on the bolts, it’s equivalent to a much higher compression ratio.
Yes, it came out in 1932 - not the Middle Ages. Albert Einstein published the theory of special relativity in 1905. In 1932 computing those forces was easily within the grasp of contemporary engineers.
I agree with this, I worked on old forklifts with flatheads, they blew head gaskets constantly. They actually needed more bolts. I started adding extra thick large diameter washers when installing the bolts and it helped considerably.
what does special relativity have to do with anything?
It is needed to calculate the engine cylinder pressure rise as the piston velocity approaches light speed.
I bought a 1950 Ford 2 door sedan with a flathead V8 in 1985, great engine. Robert Mitchum drove one in Thunder Road. The Theory of Relativity says Einstein probably had one, too, they were pretty cool back in the day.
Not only is there little beam strength it’s made worse by the wider span of the head. It has to cover the cylinder AND the valves.
It was you who implied that waaaay back in 1932 people didn’t have the smarts for computing engine pressures. As a counterpoint to this I pointed out other human achievements far beyond that, and many years previous.
Your statement that back then that they didn’t have the tools and knowledge that they do today while true is irrelevant. The question is whether they had the tools and knowledge to determine the bolts required for that engine at time. They did.
I said NOTHING about “pressures.” Here is what I said:
please try to respond to what I actually say, and not whatever you feel like pretending I said.
Lighten up, Francis.
Albert Einstein never learned to drive, and never owned any car.
Well, then, he couldn’t have been all that smart.