np435 from a 318 poly to 318 LA

[builder]

Hey guys as much as i want to keep my Poly 318 I need to replace it with a 318 LA was wondering if I could remove the flywheel from the poly and do a direct bolt on to the 318LA with out issue

[PwrWgnDrvr]

Since they use the exact same bellhousing, don't see where there can be any problem.

[Wildergarten]

Hey guys as much as i want to keep my Poly 318 I need to replace it with a 318 LA was wondering if I could remove the flywheel from the poly and do a direct bolt on to the 318LA with out issue

If the 318LA was for an automatic trans, the pilot bushing hole in the crank may be only rough bored. I don't know if the pitch of the teeth on the flywheel gear mesh with the gear on the starter motor for the 318LA.

[dodgeboykim]

LA 318 Hydraulic flywheel and A series 318 Poly Hydraulic flywheel interchange no problem. I have done that myself a few times.
Poly to LA 318 and back again to Poly. As said, Does the LA 318 have pilot bushing provision.

[PwrWgnDrvr]

I don't know if the pitch of the teeth on the flywheel gear mesh with the gear on the starter motor for the 318LA.

The starter and flywheel are governed by the bellhousing, not the engine.
Note: 66 and prior trucks used the poly 318. 67-68 used the LA318. All those yrs used the exact same bellhousing, clutch, flywheel, starter, etc.
Then in 69, the system changed to the mechanical bellhousing and everything changed, except the 318LA stayed the same as it was in 67,68.

[Wildergarten]

As said, Does the LA 318 have pilot bushing provision.

Builder didn't specify the provenance of the LA 318 he plans to install. I bought an one at a wrecking yard out of a 71 Challenger that was not finish bored for a pilot bushing; it was just a rough drilled hole. This was a huge problem for me as a 20yo kid with minimal tools figuring that out on my dad's garage floor when the bushing wouldn't install. I didn't even have a caliper. Ended up pounding it in and making a wooden jig for a reamer into the bronze oilite. Fixed it about five years later getting the crank bored when I had it ground. College age poverty doncha know.

[PwrWgnDrvr]

As said, Does the LA 318 have pilot bushing provision.

Builder didn't specify the provenance of the LA 318 he plans to install. I bought an one at a wrecking yard out of a 71 Challenger that was not finish bored for a pilot bushing; it was just a rough drilled hole. This was a huge problem for me as a 20yo kid with minimal tools figuring that out on my dad's garage floor when the bushing wouldn't install. I didn't even have a caliper. Ended up pounding it in and making a wooden jig for a reamer into the bronze oilite. Fixed it about five years later getting the crank bored when I had it ground. College age poverty doncha know.

Dealt with that myself. Used a 1" drill bit in a right angle drill and bored it myself. But I was going the other way - using an automatic forged crank out of a poly and installing into an LA with a 435.

[Wildergarten]

Dealt with that myself. Used a 1" drill bit in a right angle drill and bored it myself. But I was going the other way - using an automatic forged crank out of a poly and installing into an LA with a 435.

AKA the classic battle between "do it right" and "make it work." Almost always a tough call.

[PwrWgnDrvr]

Dealt with that myself. Used a 1" drill bit in a right angle drill and bored it myself. But I was going the other way - using an automatic forged crank out of a poly and installing into an LA with a 435.

AKA the classic battle between "do it right" and "make it work." Almost always a tough call.

Yup!
Fortunately, work trucks can handle a lot more "make it work" than vehicles in other applications. I've seen a ton of "make it work" in the Alaska bush that is beyond description.

[dodgeboykim]

Regarding lack of a pilot bushing in crank. When I installed the 74 400 BB into my 70 Fargo D 500 it did not have the crank drilled. I bolted a flywheel to engine and used a magnetic drill stuck to flywheel to drill pilot hole to size. Used closest bit i had to bushing size
and finished hole by polishing it to size.
That was 15 years ago.