i just got my TCI saturday night special converter for my "85" 700R-4 and after messing with it for hours i realized that the inner part of the converter was smaller than the smaller part of the input shaft on the tranny... the number of splines ARE the same (27...yes, i know this is 82-84...) the converter IS a lock up and is stock diameter, but by using a clucth alignment tool- that fit snug into the tci converetr and measuring the input shaft, i realized that there was a difference of at least 2/16s of an inch.

what converter can i get that will fit my transmission???
changing the input shaft is not an option-i just spent 500 dollars rebuilding the entire transmission.
( i need at least 2000-2500 rpms of stall...3000 would be nicer tho.)

 

looks like you have a 30 spline input shaft 700r4 which is correct for 85 year models.you must replace the convertor with a 30 spline.