440 Rebuild need some balance tech help

[OCTAVIOUS]

I am pulling the Numbers matching 440 HP out of my 1970 coronet R/T.
I am rebuilding and installing different 440 that is using a steel crank, non-HP Balancer and standard reconditioned LY rods.
my question is with, me still using the original 727, do I need to replace the torque converter since it has weights on it?
I do not want to modify the original because I will be going back to the original 440 HP with the 6pk rods and heavy balancer someday.

What else do I need to take into consideration?

 

[GTX JOHN]

The weight can be removed and welded back on at a late date.

 

[pnora]

I am pulling the Numbers matching 440 HP out of my 1970 coronet R/T.
I am rebuilding and installing different 440 that is using a steel crank, non-HP Balancer and standard reconditioned LY rods.
my question is with, me still using the original 727, do I need to replace the torque converter since it has weights on it?
I do not want to modify the original because I will be going back to the original 440 HP with the 6pk rods and heavy balancer someday.

What else do I need to take into consideration?

A 70 forged steel crank should not be running a weighted converter.

 

[ruffcut]

A 70 forged steel crank should not be running a weighted converter.

That was my first thought also!

 

[Curiousyellow71]

All the LY rod engines are neutral balanced and I would think vibrate with weights on the convertor of the 70-72 HD (six pack) rod motors. I would find another convertor and keep the original convertor to put back in at a later date. The balancing on the your original 440hp convertor isn't very common. You can take external convertor weights off and then it is neutral balanced for the new engine... but they are welded on. So you would have to weld them back on or have a shop do it to put the original engine back in. Makes more sense to change convertors.
They make weights that you can add to a neutral balanced flywheel to balance a HD rod engine. But, I am not aware of a flexplate that you can use for either HD or LY balanced engines with weights that can be added.

 

[Lefty71]

Can you show pix of the original weighted converter?

 

[OCTAVIOUS]

here it is out of a numbers matching 440 block and trans

 

[OCTAVIOUS]

Front of engine

 

[69Bee]

That is a cast crank otherwise it would shake the shimmy bop bop...
I agree that is should be steel with the "Six Pac" balancer, but unsure if the converter has the correct weights or not.

 

[33 IMP]

A 70 forged steel crank should not be running a weighted converter.

It might, with Sixpack rods in it.
Ist question. Was the LY rod motor balanced? With or without balancer or converter?
If it were me.... I'd keep the original balancer and torque converter with the heavy rod motor, and use a new neutral balancer and reman converter.

 

[69Bee]

It might, with Sixpack rods in it.

Actually, that is correct because of the thin weight on the balancer. I am unsure on the converter though...

 

[OCTAVIOUS]

Going forward I am putting a 68 engine in and it will have LY rods and steel crank and non-HP balancer so do I need a non weighted converter?

 

[33 IMP]

Actually, that is correct because of the thin weight on the balancer. I am unsure on the converter though...

To the best of my knowledge, the heavy rods required some sort of external weight for balance.... but it is a different weight than the external balanced cast cranks are.
In case I'm right, I would keep the balancer and tc together with the heavy rod motor, and get new stuff for the LY engine.

 

[33 IMP]

Going forward I am putting a 68 engine in and it will have LY rods and steel crank and non-HP balancer so do I need a non weighted converter?

You need a neutral balancer and converter. Was the rotating assembly balanced before assembly?

 

[OCTAVIOUS]

You need a neutral balancer and converter. Was the rotating assembly balanced before assembly?

The fresh rebuild—-It will be.

The current original motor came to me in the current condition and runs great and smooth

I am pulling it to protect the originality and to have some fun with a non matching real six pack carb set up

 

[Curiousyellow71]

The convertor and front damper looks like what I would expect to be correct for a 70Hp with HD rods.
The convertor won't work as it is on the new motor unless you want to replace the LY rods with Six pack style rods. With HD(six pack) rods you could move your damper and convertor to the new engine and have the new engine rebalanced. The Six pack rods are actually pretty common. They put them in a lot of motors in the 70s. If you are paying to get LY rods redone..you could change them and run your damper and convertor on the new engine w HD rods. If you want to run Ly rods you need a convertor that has no external weights. The two weight on both sides of the drain plug are on there to balance your 70 440hp. They look similiar to a cast crank engine..but they are not the same. I believe they are smaller.

 

[OCTAVIOUS]

I already have the reconditioned LY rods and a standard balancer I wanted to leave the original engine alone not taking it apart

I’m going to just buy a neutral balancer torque converter and have the new assembly balanced and run it

I’m only
Looking for 415 to 425 horse power and the LY rods can handle that with the new ARP bolts

 

[Lefty71]

do I need to replace the torque converter since it has weights on

so do I need a non weighted converter?

This is a question for the man who will balance the new build. I would certainly tell him what you started with as compared to where you are now. Just maybe we can learn something from you on this build.

 

[Curiousyellow71]

I already have the reconditioned LY rods and a standard balancer I wanted to leave the original engine alone not taking it apart

I’m going to just buy a neutral balancer torque converter and have the new assembly balanced and run it

I’m only
Looking for 415 to 425 horse power and the LY rods can handle that with the new ARP bolts

That is a good plan, Ly rods are good rods and are more the adequate. Many will argue the HD rods are not a upgrade over the LY's because they run the same 3/8 rod bolts and cause more stress on everything else by more rotational weight. Mopar should've used a 7/16 rod bolt like the hemi, but they never did.

 

[OCTAVIOUS]

thanks I think we got it solved.

I will report back later