273 Crankshaft Quiz

My numbers don't match yours lol, just rambling..........

1...Stick/ pilot drilling. Not sure the "track record" of 273 cranks, but you should ALWAYS check the pilot depth by measuring the gearbox shaft and same to the bell--to pilot hole bottom Generally there are two problems with Mopar cranks, and with Magnums, one more problem. A....The hole can be too shallow if it's an auto crank...B....The hole can be undersize diameter. At one time you could buy (such as Dorman) undersize pilot bushings. C...With Magnums (my former 5.9 2500pu) the pilot hole IS NOT DRILLED at all.

One solution you DON'T have available "stick it in" with an early crank is to use the later Jeep style "big" pilot bushing/ bearing which rides in the register. "I guess" you could take a late one and figure out how to turn it down to the small crank register.

2...Converter register. Never can remember they changed 68 or 69. So you'll need the small early converter for a small register shaft, or if using the early converter in a later engine, you'll need to find (used to be able to buy) or scare up a lathe and make a spacer ring between the early converter and late crank. This refers to the larger outer hole in the crank

Only way to use a newer converter/ larger snout with an early crank / small register is to have the converter "converted" to a small snout--and that could get expensive. Other than upsetting engine balance, "I guess" you could stick a later 318 crank in the 273. Even though 273's and most 318's are neutral balanced, the balance weights are DIFFERENT between the two.

3..timing/ cam drive should be no problem regardless of year, recommend use matched components and learn to check cam degree

4...So far as I know all 273's (at least pass cars) are 6 bolt cranks