Help!!! Flexplates tq dilemma

[truckinman466]

 Hopefully someone can clear this up. I have a 68 440-6 w/727. Just got a torque converter that has external weights on it. 1st question, is this the right converter? 2 ND question, do I need a neutral balanced or external balanced flex plate? 440 source say external. Summit Racing says neutral. Help me if you can.

[Cuda Cody]

I think it all comes down to how your engine was built.  Was it internally balanced when it was built?

[truckinman466]

I didn't build it. I bought it complete. Have a list of what's supposed to be in it. Not sure what to look for.

[anlauto]

I thought flex plates were neutral and the torque convertor got the weights ?

[truckinman466]

I don't think the flexplates have weights. Summit has one that is round with a bite out of it. They say it is for extenal balanced engines. I'm not much of a mechanic so I don't know what to look for. 440 source only sells neutral balnencd plates

[750-h2]

If you do not have the bell shaped weight attached to the front of your harmonic balancer you have an internally balanced engine. From the factory only 1970 and up HP 440's had this weight as they are externally balanced engines. If you have the plain balancer you need a neutral balanced torque converter. A neutral balance torque converter will have a thin flat weight welded to the side of the converter. This weight is used to give it a neutral balance.  If your torque converter has weights welded to it on the back side then its for externally balanced engines. If you do not need these weights you can take them off which will make it a neutral balanced converter. No weights on flex plate regardless.

[Chryco Psycho]

 

[RUNCHARGER]

Do you know if it has a forged crankshaft? Also I think we need a photograph on the front balancer if possible.

[truckinman466]

I just talked to the guy I bought the engine from. He says it is internally balanced. There are no weights on the balancer. So I believe the converter they sold me is wrong as it has 2 weights on the engine did of it

[truckinman466]

Engine side of it. Damn auto spell!!

[RUNCHARGER]

Okay: How big are the weights on the TC? They usually have small weights to balance them to neutral. The externally balanced convertors use much larger weights.

[truckinman466]

The weights are on the small side from what I remember. I am out of town working. They are maybe an inch by 1/2 inch if memory serves me right.

[750-h2]

When you ordered the torque converter if you told them it was for a 440 six pack their book would say that you needed an externally balanced torque converter.  The  69 1/2's are internally balanced but this is rarely mentioned in parts catalogues.