Stock hemi adapter plates

Is there a difference in the stock adapter plates through the years? I have a 55 331 hemi and a 56 354.The plates on the two motors have different thicknesses. I believe the 331 is 1/2 inch and the 354 is 3/4 inch.Are these the correct adapter plates for these years? The reason I ask is I am having starter engagement issues.When I try to crank the motor it just jams and it won't properly engage. We have tried shimming the starter to give it more room to engage but it still just jams.Does the adapter plate have anything to do with this? The starter should be the correct starter for the 146 tooth flywheel.Any help would be appreciated!

 

Both use same part 1613713 & casting 1612344 number. Sounds like one of those you have is from a diffrent engine.

 

What he said!!!

 

Would this cause the starter problem?I was thinking about taking off the adapter plate from the 331 and putting it on the 354 with the starter as well to see if it will crank it.I just didn't want to seperate the 331 motor from the tranny just yet.If this would help to figure out the problem then I will.

 

If you have the 1/2" one now, then it might need the extra 1/4".

 

doesn't seem to me that it would change the depth of the starter to the ring gear. the starter would still be flush with the edge of the block and the ring gera is located by the length of the crnkshaft.

 

The one presently on the motor is 3/4 inch

 

Go to the hot hemi heads website and ask your question there.if they don't know nobody knows.

 

You have two threads going on this question, pick one.

There 3 thicknesses of plates in total.
The starter placement, relative to the crank changes slightly because of pinion design and tooth count (which changes flywheel diameter).
In the applications using the 146 tooth wheels I have found (by mixing parts) that there can be as much as 0.040" difference in location.