What is a "Late" L head?

purple72Gremlin wrote: BassBoat wrote: AMC engineers Carl Chakmakian and Les Viland drove an overdrive-equipped American from Los Angeles to Miami. Driving at an average speed of 40 mph and under National Association for Stock Car Auto Racing (NASCAR) supervision, the Rambler achieved 35.4 mpg -- " Yeah  at 40 MPH.  If you drove like that today, you would get a ticket for going too slow &/or you very likely will find somebodys grill right up to your back seat.  people dont drive 40 MPH.....................................

It depends on where you live and what your commute is. I go 40-45 everywhere around here in my Scout, and then on the interstate I'll cruise in the right lane doing 55.

My uncle in Michigan doesn't own an actual car, he drives his golf cart everywhere. It might sound stupid, but it works for him and he doesn't get pulled over for it or cause any harm, so why not? It's a practical EV in the town he lives in.

The "late" L-head is actually a 1964-65 model. It has the bosses in the sides for the three point motor mounts (one each side, one under trans). Earlier blocks use a four point mounting system and have a plate behind the timing cover with a lip on ht lower edge for the front mounts, the rear two mounts are on the bell housing.

What Billd said about the water pump is true -- 41-55 model L-heads (first appeared as a 172.6 in the 41 Ambassador 600) have the water pump on the left side driven from a shaft off the back of the generator. 58+ model have the water pump in the front of the block. You can mount any model engine in a 63 and earlier American simply by swapping the plate from the original engine to the late model, but you can't mount an early engine in a 64-65 American due to nowhere to bolt the mounts. Well, it could be done, but it won't just bolt right in.

You should be able to get mid 20s from the American with sedate driving today, even at 50-55 on the Interstate. I wouldn't push it much more than that if mileage is a concern. As someone pointed out, those 30+ mpg runs were at low speeds, but mostly rural driving. You should be able to do about the same today even on the Interstate -- just cruise at 50-55 and don't get in a hurry getting up to speed, but don't let it drop under 45 even pulling up a hill. Once it drops to less speed than that in high gear it takes a while to build speed back up. There was a lot of stopping and starting and more hills on roads in the 50s, the steady cruise on the Interstates should make up for the starting and stopping. I wouldn't be surprised it you couldn't get close to 30 mpg with very careful driving in light to medium traffic.

farna wrote: The "late" L-head is actually a 1964-65 model. It has the bosses in the sides for the three point motor mounts (one each side, one under trans). Earlier blocks use a four point mounting system and have a plate behind the timing cover with a lip on ht lower edge for the front mounts, the rear two mounts are on the bell housing.

That blows me away that they ran that motor up until 1965! I LOVE this car! I am so sick and tired of working on late model cars electronic computerized crap! Talk about basics, open the hood of my American. :)

Believe me, about 95% of the driving I do a very basic 10 12 batterys and a motor hooked to a VW transaxle would be PLENTY. I drive down surface streets with a max 45 mph four miles each way and that is about all this car will be asked to do.