[scott70]

Originally Posted by mgarblik

Chances are the engine shop that balanced the crank would know "how" they balanced it. Most shops have a standard way they balance various crankshafts by application. If a customer presents a Pontiac crankshaft for balance, most shops would be aware of the slightly different way "partial" internal balance crankshafts are done. They would have asked the customer if they wanted a "full internal balance using a neutral balance flywheel", or a stock balance. At my school, we like to do a full internal balance because it opens you up to any one of many options for flywheels and pressure plates in the future. If we do a stock balance, we balance with the flywheel only added to the rear, no pressure plate. Once that's good, we bolt on the pressure plate and spin it again to see if the balance remains correct. Then if needed, fine balance the pressure plate with tiny magnets to get it just right. Mark the location, weigh the magnets, switch the magnets to washers and weld them to the pressure plate. Good quality pressure plates generally don't need any attention other than a check spin.

Engine shop just emailed me and said it’s ready. He said he couldn’t find the balance card so he made the new flywheel like the old by adding a weight.

[mgarblik]

That's good news and a good catch on your part.

[scott70]

They had to add weight to the new flywheel to get it to match the old flywheel. And still have to index the PP because the new McLeod PP was off quite a bit from neutral balance. He said if I don’t put it where it needs to be it will off by around 11 grams. I noticed also the new flywheel isn’t as thick as the original so let’s hope the starter and everything lines up. Sorry for jumping on your thread but it seems like it might be helpful and related