"........Look at the starter. If the bolts are straight across (stock gm starter) then it's designed to work with the 153 tooth flexplate. If the bolt pattern is staggered (gm starter) then it's designed to work with the 168 tooth flexplate......."

Yup.

As I recall a The starter for the 168 tooth when tried with a 153 tooth flex plate will not even engage with the flex plate teeth (but will bolt up).

I don't think you can even bolt up a starter for a 153 tooth flex plate to a 168 tooth flex plate as the nose won't clear the flex plate.

If the starter turns the motor over but grinds you might just need the starter shimmed a little. You also want to make sure you use the starter specific bolts.

On the bright side if it's just a starter/flex plate issue all you need to do is change the starter, not split the engine and trans to change the flex plate.


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