I will be listing my Dad's '15 roadster on Ebay in a few days. My purpose is not to drum up interest, but rather to find out what to look for on the motor to describe it better. It has a Fronty head with a brass Carter carb. It also has a Model A type crank pulley and crank ratchet. I was hoping someone could tell me what to look for without dropping the the inspection plate/sump to determine if it has an A crank. We know T's, but this our first rodeo with an overhead motor or anything other than a stock T crank. I will be getting the car out later in the week and will try to get a few pictures of the head to determine what model it is. Thanks for any information.

Post some pics of the various parts/engine /chassis etc, and we will identify what you have prior to putting it up for sale if you like.

I will be posting pictures (if I can figure out how) tomorrow.

Look at the front of the crankshaft. Normally the A crankshaft will have the screw in cranking ratchet on the crankshaft rather than the ratchet on the hand crank like on a normal T.

I haven't had any experience with an A crank conversion, but isn't there a spacer about an inch thick required between the crank case and the pan? Dave

Thanks, Dave. I will look for that today. I have also heard that you must dimple the pan for the throws to clear, is this correct? If it has a spacer between the block and pan it must have a something other than a stock T crank. Is this correct as well? Thank you all for your input.

Danny, the spacer goes between the pan and the pan cover, not the pan and the block.

If the A crank hasn't been shortened, the block is moved forward on the pan nearly an inch, and the old holes will probably show.

rdr
Had a full length A crank engine, and didn't like all the compromises. Junked it when 3 cracks in the crank and 5 in the block were found.

Thank you for that info Ricks. I know that it has an aluminum sump in place of the inspection plate. If it doesn't have a seperate spacer could it be built into the top of the sump? Also, wouldn't you have to move the front dam in the pan forward to match up with the block? It has a narrow-neck pan. Is this possible with an early oil pan? If the block is moved forward then there must be a spacer between the block and hogshead? Thanks for your response.

Danny, one of my sons has an "A" crank shaft in a TT truck. The shaft has been shortened to fit the T. He had to dimple the pan on the sides to clear the rods, but he did not use that spacer under the pan inspection plate. It fit without it. So the only thing showing is the small dimples in the pan.
He also put a chevy OOPS overhead valve head on it. I will run faster than I like to go.
I will post a picture taken at a recent "Texas T Party" tour where he was helping as a "Vulture Wagon" (rescue trailer)

Thank you Willie. What kind of wheels are on the rescue trailer?

Danny, you have a good question. I don't know, if it fit it is used for something like that. Lots of stuff gets picked up at swap meets and from friends.
I do not have the picture here to post, but there is a single axle trailer that came out of the Fredericksburg Texas area that is ofter used with the truck. It has a heavy truck type rear end and is hooked up like an 18 wheeler.(5th wheel). When we got it, the rear end and 4X6 (approximately) woods frame was there. It was made by the Martin Wagon co which later became Lufkin Trailer an 18 wheeler trailer company. My son had it in Indiana for that 100 birthday bash. The trailer is about 20 ft long.

Sorry, I did not intend to Hi-Hack your posting.

There are no dimples or spacers or re-drilled holes in the pan. This is the only thing that makes me think it might have an A crank. Can anyone offer an explanation?

That would be my guesss!

Bottom view. Carburator

Is there any way to mount the crank ratchet in the picture to a T crank? It looks like it is threaded and screws onto the front of the crank. A Model T crank is of course, not threaded. Also, isn't an A crank a larger diameter, which would require a bushing or sleeve to be installed and then threaded to accept the pulley? Seems like alot of work just to run V belts if this is a T crank. Are any of the accessory T cranks threaded at the front pulley?

The T crank is 1 3/16" diameter forward of the front main IIRC, so yes, I don't see why that model A starter cam couldn't be fitted. If there is no 3/8" diameter hole up there, I suppose the T crank could have had been cut off just aft of that hole, and drilled and tapped to accept that model A part.

The stroke on a model A is 4 1/4", a 1/4" longer than the T.

Can you figure a way to measure the stroke through the plug holes?

Seth, It has a Fronty head on it so the plugs are on the side, not the top. I guess it could be done, but it would have to be something flexible.

I think, if I was you, I'd be spending some time figuring out how to do it since you aren't interested in dropping the pan to find out for sure.

You could always fill a cylinder with heavy oil with the piston at BDC and then turn the crank and pump the oil out and measure the volume of it.

stock bore/T crank: 44.2cid/ 724cc
0.030" overbore/T crank: 44.9cid/ 736cc

stock bore/A crank: 46.9cid/ 769cc
0.030" overbore/A crank: 47.7cid/ 782cc

Sure, Seth. I'll get right on it. I'll be sure to let you know the results.

No need in that Danny, I couldn't care less.

I was just trying to be helpful, that's all.