I’ve seen this type swap on many cars that I would call marginal !! What I mean by that is a car that may or may not have enough horsepower to pull the power glide!! Generally speaking the cars I’ve seen with the numbers you have given actually slowed down in ET.. The cars just didn’t have the power to pull the power glide !! The higher horsepower cars seem to do really well with the swap !!
Thanks for the info that’s kind of what I was thinking as well. Car has a 383 making about 525 hp best ET is 10.86@124 but I do plan on putting a 451 in it next year which hopefully should make enough power to pull through it.