I would like to know if a 1954 plymouth 6 engine will fit in a 1948 plymouth. I have the 54 engine out and have compared it to the 48 and it looks and measures out to be identical. I would hate to rebuild the 54 engine and then find out it would not fit!!! Thanks. john d.
It is my understanding that any 1933 through 1959 Plymouth or Dodge passenger car L-6 engine would be a direct bolt in for your 1948. If you are trying to put a newer engine into a 1933 or 1934 then there are some issues with the starter/bellhousing. However, you don't have a 1933 or 34.
If you get a Dodge engine then it might have a different number of bolts on the flywheel if it had fluid driver. I understand that that is not a problem.
Canadian built cars, DeSoto and Chryslers and the larger Dodge trucks used a different longer block that can be made to fit but modifications to the car would be required.
John - make sure the '54 engine is not from a HyDrive car. That car mixed engine oil with the transmission and is a breed of a different color. It will fit but that is the least of your worries!
Don't tell anyone, but the engine in my 46 coupe is out of a 56 p28. Since the 56 was a 12V car, I swapped the genny starter. there is also an issue with the exhaust manifold, as the dump on the later engines is under cylinder #5 instead of being all the way back as on the P15's. If you need to interchange the distributors, swap them unit for unit, the newer engines have a different body casting and use a different dist cap. The early one have a shallow distbody casting and use a taller dizzy cap, the later ones have a taller dizzy casting and use a shallower cap. Don;t know when they changed but I do know when I tried to use a later dist with the older cap, the rotor and the lugs in the cap don;t line up and you don;t get spark. You may also need to swap coolant pumps as there were a couple of varients. And wathc your fan clearance, I used the later one and it is a little deeper, Probably should have deleted the little spacer things, but I only have about 1/8 inch clearence between the fan and radiator. Other than those considerations it is a bolt in. My engine had a 6 bolt crank to flywheel connection. I used the 56 set up with the 46 bellhousing clutch etc.
Pic of the engine on the stand
(https://www.plymouthowners.club/talk/proxy.php?request=http%3A%2F%2Fimg.photobucket.com%2Falbums%2Fv67%2Fgonyagl%2F95231e30.jpg&hash=9188b69b8fbed54f1f7c82a37c13763f3cc63c23)
I know your radator support can be turned around for more fan clearence when installing? a v-8 maybe this would work for you too.? ? Mike wagnon