The Ford Barn

flatmanweb · 01-17-2025, 08:49 AM

Can someone give me the length of a bare 1946-48 engine block from the front where the cam cover bolts on to the rear where the transmission attaches?

The reason I need this is because I have a 296 CI engine in my 34 roadster that many years ago had the flywheel explode and it broke off most of the bell housing.
Another bell housing section was used to repair it but it has had bad clutch chatter ever since (for the past 40 years). I have done every thing possible to correct the chatter except level the back of the bell housing to match the front of the block. My machine shop can do this but I would like to know the correct original length for reference.
Thank you in advance.

Ken/Alabama · 01-17-2025, 07:02 PM

Looks like 25 5/8”.

Bored&Stroked · 01-17-2025, 08:21 PM

If it was mine, I'd just have them true it to the front surface . . . the exact length will make no real difference (as long as it is close) in that the input shaft of the transmission slides into the clutch disc.

But just because the surface of the mount is parallel to the front does not mean that the centerline of the mounted transmission is exactly where it should be. This could be very important and be the cause of chatter if it was off.

About the only way to check that is to have the block stripped down and come up with a way to mic the centerline of the transmission shaft as compared to the crankshaft. I can think of multiple ways to do this . . . one would be with a "hogs head" adapter where I could indicate on the hole that is bored into it (using a dial indicator mounted to the crankshaft flange). Or you could mount a transmission and mic the input shaft to the rear main bearing bore. Lots of options with some creative work!

38 coupe · 01-17-2025, 10:31 PM

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Either a hogs head or an empty transmission case should work. Put a small magnetic base with a dial indicator on the crank flange, or on the flywheel if there is room, and see what the run-out is.

01-17-2025, 08:49 AM	#1
flatmanweb Junior Member Join Date: Dec 2015 Posts: 11	59A engine block length Can someone give me the length of a bare 1946-48 engine block from the front where the cam cover bolts on to the rear where the transmission attaches? The reason I need this is because I have a 296 CI engine in my 34 roadster that many years ago had the flywheel explode and it broke off most of the bell housing. Another bell housing section was used to repair it but it has had bad clutch chatter ever since (for the past 40 years). I have done every thing possible to correct the chatter except level the back of the bell housing to match the front of the block. My machine shop can do this but I would like to know the correct original length for reference. Thank you in advance.

01-17-2025, 08:21 PM	#3
Bored&Stroked Senior Member Join Date: Jan 2011 Location: Central Ohio Posts: 5,723	Re: 59A engine block length If it was mine, I'd just have them true it to the front surface . . . the exact length will make no real difference (as long as it is close) in that the input shaft of the transmission slides into the clutch disc. But just because the surface of the mount is parallel to the front does not mean that the centerline of the mounted transmission is exactly where it should be. This could be very important and be the cause of chatter if it was off. About the only way to check that is to have the block stripped down and come up with a way to mic the centerline of the transmission shaft as compared to the crankshaft. I can think of multiple ways to do this . . . one would be with a "hogs head" adapter where I could indicate on the hole that is bored into it (using a dial indicator mounted to the crankshaft flange). Or you could mount a transmission and mic the input shaft to the rear main bearing bore. Lots of options with some creative work!

01-17-2025, 10:31 PM	#4
38 coupe Senior Member Join Date: May 2010 Location: South Texas Posts: 2,040	Re: 59A engine block length Sponsored Links (Register now to hide all advertisements) Either a hogs head or an empty transmission case should work. Put a small magnetic base with a dial indicator on the crank flange, or on the flywheel if there is room, and see what the run-out is.