The Stovebolt Site Forums The Shop Area Engine Shop ENGINE DEBATE?

I hope this isn't to boring of a question ?A friend of mine came over to look at our old truck.1942 1&1/2 ton 235 chevy,he claim's it is not the original motor because it is not a flat head.He claims chevy did not make an over valve head motor till the 50's.I told him i checked the casting numbers and it came 41-46 that was the block used.Thank's for any info,Chad

Chad,

Bet your friend a dinner out at a fancy restaurant...tell him you think he might be right but that it's worth the bet. Then set the hook! I will say they never, ever, even thought about a flat head engine. Experts are watching so I better be careful.

Stuart

Nope, no flatmotors in a 'Bolt! The closest to that type would have been the early T head engine used in the Classic 6, made roughly from 1913-1916. That engine was never used in trucks.
Now, some GMCs used flathead engines, but they went to OHV by the late '30s.

Stuart thank's I really thought i was losing it.I didn't thing chevy made a flat and i really didn't feel like having a debate it was late last night and i had to get up at 4 am for a 10hour work day.I tried searching the web for documentation to print out ,but nothing being specific that the motor's were overhead or flat head.Thank's again i can taste the dinner now,or i'll settle for a few cold one's.Chad

Your buddy has Chevy confused with Ford. The first Ford OHV 6-cylinder came out in 1952. Their V-8 went from flathead to overhead valve in 54. Until then, they used a flathead 6, from about 42 to 51, and the 4-cylinders and the V-8s were around from the T-model days on forward. The flathead V-8's had a production run from 32 through 53, in about 4 or 5 different displacements.
Jerry

Careful how you structure that bet. Chevy didn't put a flathead in that truck, but it may not be a 235.

I don't remember when the first truck 235 was made, but that early it sure could be a 216.

the first 235 came out in 1941. It was an option on big trucks.

There is an incomplete (and maybe incorrect) listing of casting numbers in this table.

Tim

Thanks much for the imput 235-216 i'm not sure i just know it turned 4300 miles.And i do believe the previous owners on the milage it came from their home town and they know the previous owners right back to the fire department that purchased it new.It is a real pleasure driving it and so far hasen't let me down.Thanks again on all the info.(KEEP IT BETWEEN THE DITCHES)Chad

tell friend not too bright or just a mopar lover...doc

Correct me if I'm wrong but I think Chevy came out with the Stovebolt 6 OHV in 1929. I don't think there was ever a flathead Chevy. Your buddy is confused. Make the bet and then collect on it!

Actually, the '29 engine was the second Chevy 6, though it was the first to be called a "Stovebolt". The first Chevy 6 was the "T" head engine I mentioned in my first post. It was only made for a few years in the Classic 6, a luxury type car that Louis Chevrolet really wanted to have his name on.

LongBox55 is right. The reason for going to overhead valve was better breathe ability. Flat heads didn't breathe as well. If I am not mistaken the T head had a valve on each side of the cylinder. An F head had a valve in the block and one in the overhead. Military jeeps had some of those. They ran good. Nothing like a GM bolt though. BTW, I went to the Show and Shine this past Saturday and there were about 5 bolts there. All the rest were V things. 55-59 Chevy pick ups were there and many classic cars and trucks including a Diamond T. One bolt was in a 41 Chevy 2 door car with a 292 matched to a T-5 trans with 3:00 gears. Has a 500 cfm Edelbrock 4 bbl, balanced and cast iron headers. Sounded great and gets 20 mpg in town! Had chrome valve cover and chrome pushrod covers. Two bolts were in Chevy pick ups. They were 235s all rebuilt. It was nice to see at least a couple of inlines there. About 200 cars were there. Great show here in Medford Oregon. Just a nickels worth. Henry

Don't forget the few V8 Chevy's made in 1917, and some leftover engines used in 1918.

Grigg

Henry G, you are correct. The T head engine has valves on both sides of the head, each side operated by their own cam. You see those F head engines on Willys vehicles up into the '60s, the famed Hurricane 4 and 6 cylinders. GMCs did run flathead Olds based 6 cylinders (and a few Pontiacs, too) until the 228 came out. It had actually been used earlier, in 1/2 ton panels, on an off and on basis as that model wasn't made in all years. In that model, the engine was referred to as the "Buick type 6 cylinder", as that was it's original heritage. I'll get the exact dates of production. They're listed in the book GMC, the First 100 Years.