What is longest a main cap dowel can be?
 

Ford guy gave me a handful of new Ford cam 1.5" dowels. I know many use the Ford cam dowels, also know there are other options out there. That said, I think 1.5" is too long, maybe cut them down to 1" or less. Thoughts on max length?

Looking at dowel holes I see some are drilled deeper than others.#1 driver's side even has a small hole where the bit tip went through, obviously deeper than others. Driller Dude must been tokin' and looking and porn that day...

I have had them go thru the caps.One issue you need to have a cap puller to get them off the dowels.Tom

Interesting. The 400 block I'm currently building had all 4 bolt main holes drilled and tapped except for one. It had a spot where it looked like they started to drill, like a sixteenth deep, then the 5 o'clock whistle blew.

Even back in those days, all those holes were drilled at once with 6 drill bits. Chances are one bit broke off in a previous hole and the next so many blocks went through with 5 holes drilled until someone noticed. Had a SBC years ago in the shop that had killed several sets of rod bearings over time. Found a broken drill bit piece in the passage about 1/2" long. Enough oil could make it around the bit flutes that it wouldn't kill the bearings immediately. It happens in mass production.

Are these .3095" diameter or something else?

Since the factory caps have the holes drilled all of the way through, I would not see a limit on the length other than making it hard to get the caps off. If you have aftermarket caps with blind holes, then you need to measure.