How to tell if flywheel is iron or steel

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MoparMike1974

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I have a 11" flywheel from a 69 383 that i'm thinking about using. I'm sure its not the original wheel but i'm not sure if its iron or steel. It has the numbers 40 30467 stamped into it but I haven't been able to find anything online. The pressure plate was yellow and diaphragm type.
Is there any easy way to tell what its made of?
 
Hit it with a grinder. If it sparks should be steel.

Steel is 3x the money vs stock ductile iron flywheels.

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If you paid for it, it's iron...

If you took it without paying, it's steal....
 
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LOL what?? Both steel and iron are magnetic.

:lol: Yes and make sparks when ground on with a grinder although different colored ones but sparks none the less. Bright yellow sparks Steel and Red to Orange iron
 
Just buy a new one. Do you really want a 50+ year old non SFI cert 30 pound disk spinning up to say 6500 rpm’s 6 inches from your feet coming apart?

Scatter shield also…. Just a thought…
 
Well to answer the poster's question, an iron FW will typically not be fully machined all over and show some rough cast surfaces on one or both sides. In addition, if there are raised cast numbers or letters, it's iron. Steel FWs are fully machined all over, have no rough pebble like cast surfaces, and if there are any numbers or words they are stamped in.
 
Iron sparks are shorter and darker orange. Steel sparks are longer; with a lot of split ends; and lighter in color; yellow. If you take a pic of the sparks you can count the splits and determine the exact hardness.
 
Well to answer the poster's question, an iron FW will typically not be fully machined all over and show some rough cast surfaces on one or both sides. In addition, if there are raised cast numbers or letters, it's iron. Steel FWs are fully machined all over, have no rough pebble like cast surfaces, and if there are any numbers or words they are stamped in.
That's what I was gonna say. If it has texture like a cast iron head or block, likely cast. Smooth on the non clutch side, probably steel.
 
Thanks for the reply's. I will post some pics this evening. Im leaning torwards buying a new wheel since my goal is around 600 hp. Not sure im willing to chance it. I will sell this wheel for someone who is doing a mild build as its in great shape.
These 11" wheels are expensive. Cheapest ones come in close to $400.
 
Yeah dont worry, I wasnt going to grind on my flywheel.
Here are a couple pics of the flywheel. Its fully machined so no obvious rough areas like a cast part would have. Additionally, the numbers are stamped in.
Heavy? Hell yeah. I was thinking about 35 lbs. Threw it on my scale and its a whopping 40.2 lbs.

Flywheel_Front_A.jpg


Flywheel_Front_B.jpg


Flywheel_Back.jpg
 
I have a 11" flywheel from a 69 383 that i'm thinking about using. I'm sure its not the original wheel but i'm not sure if its iron or steel. It has the numbers 40 30467 stamped into it but I haven't been able to find anything online. The pressure plate was yellow and diaphragm type.
Is there any easy way to tell what its made of?
Pick it up, you'll know.
 
Looks like a steel wheel with a fresh Blanchard grind. I'd run it.
Though, I did LOVE my aluminum flywheel. Need a lot of gear to make an aluminum wheel work well.
 
Yes, I just had it resurfaced. Second pic is cosmolined since it will be in storage a while.
I will probably buy a new one because its heavier than I need.
 
Does it ring when you tap it with a hammer it is steel. If it is a dull ring or almost a thud it is cast. Just like a crankshaft.
 
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