Flywheel and torque converter

[tparker]

Didn't really think about this. The Buildshop needs my flywheel to balance the engine. My flywheel is welded to the torque converter. I just ordered a new custom built converter but I didn't ask if that was part of the build or not. How common is it to have them welded together or as two separate components? I'll call Monday to confirm then order a seperate one if need be.

Thanks
Tom

[JP426]

Maybe they just need the flexplate? Mopar automatic cars don't have a flywheel. I think all Mopar torque converters have the starter ring gear welded to the converter. I haven't heard of anyone needing the torque converter for balancing the engine internals. There are balanced converters though.

Maybe someone else can chime in if I am misunderstanding what you are explaining.

[73_Cuda_4_Me]

The ring gear for the starter is welded on the torque converter, and that bolts to the flex plate that gets mounted to the back of the crank.

What engine are you using??? Small blocks came either 'internally balanced' for earlier years up to 71, or later years (72-74 I believe) were 'externally balanced' with a weight on torque converter and a weighted harmonic balancer on the front.

If the shop is doing balancing, you use a neutral balanced TC and harmonic balancer... I don't believe they need either to balance the engine internally.

Someone else here will probably chime in with a more educated explanation.

[7212Mopar]

TC, flex plate and harmonic balancer are different depending if you are building an internal or external balanced engine. If you are installing a new crankshaft, better to go with internal balance. What did you ask the engine builder to build? All they need is the crankshaft to do the balancing. Then weight the pistons and rods to make sure they are within like a gram or less from each other.

[tparker]

Thanks all. I guess I thought the flywheel was bolted to the torque converter but its the ring gear and its welded. I did a quick search before I posted and some "flywheels" showed up on google but I didn't look at the results in detail.

I'll have to talk to the engine builder. He asked for the balancer and I thought he said flywheel but maybe he meant flexplate. It is a 1970 340, so it should be internally balanced, right? I got a new SCAT crank that should be the internally balanced one. I'll have to talk to him and make sure they doing this right. Hopefully it is just a mixup.

Second question, do they do the balancing with the crank in the engine or on a jig? I always assumed it was done in the engine but some youtube videos showed a jig. I guess that makes it easier to work on.

[anlauto]

if he said "the balancer", that's usually on the front of the engine

[7212Mopar]

I think Scat stroker crank cast or forged are both internal balanced. You might want
to double check with them. 70 factory crank should be forged.

[Strawdawg]

give the shop the flex plate and the balancer.

[tparker]

if he said "the balancer", that's usually on the front of the engine

LOL, I got that part.