400 rods vs mid 60's 383 rods ?

[Cranky]

Any reason why a late model 400 rod won't work in say a 66 383? I know the 383 used a forged crank and the 400 was cast so maybe there might be a weight difference in the rod?

 

[rmchrgr]

Same rod. Same journal size, same stroke. I recently took apart a '70s 400 which actually had had a forged crank and a really nice set of #1737692 rods.

 

[Cranky]

Same rod. Same journal size, same stroke. I recently took apart a '70s 400 which actually had had a forged crank and a really nice set of #1737692 rods.

Yup, some early and hi po 400's came with a forged crank and so did the ones (or most) that were used for early warranty work.

 

[IQ52]

Again...400's that came from the factory in front of a manual transmission, be they in passenger cars, trucks, Trail Dusters or Ramchargers, were supplied with forged steel cranks.

 

[dsd1967]

Again...400's that came from the factory in front of a manual transmission, be they in passenger cars, trucks, Trail Dusters or Ramchargers, were supplied with forged steel cranks.

I'm putting a 400 into a 67 D100 and have a couple questions based on this statement.
1. Are the forged crank 400's externally balanced just like the cast crank 400's.
2. Without pulling the pan is there a way to tell if it is a forged crank
3. I'm using a torque converter from a 78 440....will it balance correctly with a 400

 

[BeepBeepRR]

I'm putting a 400 into a 67 D100 and have a couple questions based on this statement.
1. Are the forged crank 400's externally balanced just like the cast crank 400's.
2. Without pulling the pan is there a way to tell if it is a forged crank
3. I'm using a torque converter from a 78 440....will it balance correctly with a 400

 

[rmchrgr]

Was not trying to start a debate about whether 400s had forged cranks - jut mentioned it as an aside.

Regardless, "muscle era" B engine (383/400) rods are the same - 3.375" stroke, 2.375" journals, 1.094" wrist pin bore, 6.358" long. Don't quote me on this but they may have even had the same part number (1737692) through the entire low deck run.

So the answer is yes, '70s 400 rods will work in a '66 383.

 

[Nate S]

I have a set of '64 361 rods and crank if you need them. Same as 383. Gathering dust and getting in my way.

 

[IQ52]

I'm putting a 400 into a 67 D100 and have a couple questions based on this statement.
1. Are the forged crank 400's externally balanced just like the cast crank 400's.
2. Without pulling the pan is there a way to tell if it is a forged crank
3. I'm using a torque converter from a 78 440....will it balance correctly with a 400

Forged crank 400's were internally balanced.

 

[Cranky]

Again...400's that came from the factory in front of a manual transmission, be they in passenger cars, trucks, Trail Dusters or Ramchargers, were supplied with forged steel cranks.

I've been messing with Mopars for a lot of years now and know that 'mom' didn't always follow her own rules. What was supposed to be sometimes wasn't. I know you have much more experience than I do and respect your knowledge but after parting lots of cars over the years (mainly in the 70's), I've found out that there was always the exception like cranks drilled for a stick that were in automatic vehicles for example. And I'm not talking about something that someone put together. Most of the stuff I got was untouched as far as not ever being rebuilt and it's not that hard to tell when someone has been into one. There's always a tell tale sign. Even found a 79 Dodge Magnum with a 440 in it and that wasn't supposed to happen from what someone in the know told me. Guess where that thing was....on a dealer's showroom floor in Lake Charles LA. Did a double take on that one but the window sticker listed it and had to dig deeper so checked out the pad on the block and sure enough, it was an RB engine.

 

[dsd1967]

Forged crank 400's were internally balanced.

OK....so I did a little browsing and saw a picture of a cast crank 400 harmonic balancer and that is definitely what I have. I had the pan off to change over to a truck pan....and I swear that it was a cast crank, but what throws me off is that I also swear that it had a pilot bushing in the end of the crank...I'll have to verify that tonight. I was pretty sure it is a cast crank motor until I saw the statement that all stick shift 400's got the forged crank.

What I do know is that a friend had this motor in a 67 Polara convertible with an auto behind it and it ran smooth as silk. He just wanted a 440 upgrade.

So circling back to another question I had above.....would a 78 440 use the same torque converter weights as a cast crank 400?

 

[66Satellite47]

The pilot bushing thing seems very inconsistent. I got a couple 440 steel cranks that came from 727 cars with the full drilled crank but no bushing, One that had the bushing too but 99% sure it came from an OEM 727 car. One of my 400 cast cranks out of a cop car had bushing with the 727.
Not sure, thought the cast 440 cranks used a different converter weight & position than the 400. 440 balancer is completely different than the 400.

 

[66Satellite47]

The 400 rods will work fine, 99% sure re-balance required due to the large bore size difference.

 

[dsd1967]

I just got home and confirmed that it does not have a pilot bushing.

Now to figure out the 400 vs 440 torque converter weighs. A quick check on rock auto show’s the same part numbers offered for both but how accurate is that.

Sorry for the thread hi jack

 

[66Satellite47]

Mopar performance had converter weight kits with the location templates for different engines. Check that out.

 

[IQ52]

I just got home and confirmed that it does not have a pilot bushing.

Now to figure out the 400 vs 440 torque converter weighs. A quick check on rock auto show’s the same part numbers offered for both but how accurate is that.

Sorry for the thread hi jack

The cast crank 383's (1971 2-bbl) and 400's use the same weight offset as the cast crank 440.