Hello all, I am having bad luck with the search engine of this site. I did look. What I need is an answer of flywheel balance and front weight.

I have a stock 79 sa auto, which I am converting to manual. I considered the racing beat mid weight, but then changed thinking I will have to over modulate the clutch and fuel. My thought was the lack of torque will become even more pronounced when the flywheel is lightened too much. I understand that a light flywheel allows quicker revs, which is nice, but maybe not worth the trade off.

I realize the 79 had a 30 lb flywheel. Will a 81-83 23lb flywheel go in without any balance issues? Do I need to address the front weight in either of the above situations?

It appears that the 30lb goes in without any additional work. Is the same correct for a 23?

This was the RB's biggest plus in my book. It appears to be neutral balanced and simply bolt onto the factory counterbalance weight with 6 bolts, leaving the factory balance intact.

The RB flywheel is 304 dollars. I can buy a factory one for near 100 dollars, and have a fresh resurface for near 50 dollars, so cost wise a used factory wins too.

I thank you all in advance. This group has been more than helpful to me!

Rich

 

81-82 should be fine and if there is an issue, it is barely noticeable. I have a spare 215mm aluminum flywheel if youre interested. Lmk

 

Yes, the 81 or 82 stock manual tranny flywheel fits up, is balanced the same and is only 23lbs.

 

So, even though it is lighter it still uses the same front counter weight?

 

I use the 82 23lb flywheel on my stock engine and its not a problem. Revs a bit quicker but keeps
the momentum up between shifts, so quite driveable. This was an old SCCA racers trick back in the
day to get the edge on the guys running the stock 30lb flywheel. No harm from it.

The difference in the counter weighting is negligible.

 

Thank you all again. Watson, my guess is the weight of the front weight will be off, but not enough to cause an issue. I am basing this guess on people who have done exactly this. Even though there is 7lbs of weight difference, there is the way the weight is distributed in the mass to offset that.

Production "balancing" is pretty sloppy. They use a fairly large range that works. Then there is the potential for tolerance stack.
I have taken factory motors ( Chevy, Mopar, and HD) and some of the factory variances were hard to imagine. I had a factory 440 that was off 25 grams from the lightest to the heaviest rod. This motor had no unusual vibrations when running.

If I ever take it apart, I will figure out how to balance the assembly. As it sits though, it looks like I am on the hunt for a 23 lb flywheel!!!

Thank you again, this place always has the answer!!!!!

Rich

 

the engine rotors are the same, 76-82 so the balance weights are the same, even though the flywheel weights change