Your advice is best so far

we have tried lower start rpm but not much difference there
and I have tried my share of converters, this one is a swap meet find 8" and the best one so far
I have two 8000 rpm 7" converters ,slightly different,both made by very well known manufacturers, but both slips so much down track that the car was 2 tenths slower and even slower in the late rounds, we even tried a external cooler( leaf blower )

seems like I need to invest in a G meter