5.9 Magnum flywheel - DIY with bolt-on weight??
There's a few questions asked.
I appreciate input but specifics are nice to have. :-k
Okay. Specifically. The appropriate specs for the flywheel, (size, balance, et al) are in the Mopar Performance engine manual. Follow the recommendations there and you should do fine.
Short of that.
Cutting down a flywheel and installing a ring gear is sketchy unless you find a good machinest with experience in this operation. (Not many left).
143 tooth flywheels are big. They require bigger bellhousings and it also moves the starter out which will get entertaining when you go for headers/exhaust. I don't recall if many A bodies came with the bigger set up, if they did, they weren't common. So finding a bell would become a treasure hunt.
You could try and modify your 318 cast flywheel for the McLeod bolt on weight. But remember that it is bolting on to the engine side so there may be some block interference issues. The McLeod flywheel is the same for all Mopar engines, (respective to size and bolt count), it's the weighting that is different. McLeod's flywheels have a recess that the weights bolt into. Notice that the prefix on the part numbers are the same and the suffix is different. The suffix number, 15A, 12C, 44Z, whatever is the weight and the location on the flywheel where it bolts.
You could take your 318 cast flywheel to your local machinist and have them counter drill it to balance it as outlined in the Mopar Performance manual. If they have experience in it, you should be fine. I don't know what the costs would be in your neck of the woods, but you would be shocked at what I was quoted by a "friend". Hopefully they follow the instructions correctly or you're gonna have this weird off idle vibration that will come back in a bit further up range. Or they do it really wrong and you get a flywheel that cracks and sends pieces out at speed.
Or you can spend a few extra bucks and get the correct quality piece for your car that you can have confidence in.
The whole billet, aluminum, cast or whatever flywheel thing has to do with intended use of the vehicle, type of vehicle and inertia.
