Cracked flexplate question

If it is a nuetral balance convertor (for internally balanced engines like 318) and you're using a stock flex plate that is a problem. Should be causing a noticable vibration idling though. You might want to try a B&M weighted flexplate designed for use with a nuetral convertor and 360. Besides providing the correct balance for the convertor it is much stronger than stock. https://www.summitracing.com/parts/bmm-10239/overview/make/dodge