Not sure if anyone here will use this. But I stumbled a site that showed all the different gear ratios for the several transmisions. I threw it in an excel sheet and wrote some equations. Basically if you put in your Gear, Tire, Converter loss and RPM it will give you mph for both a locked and unlocked converter. Might be helpful to figure out what you need.

http://73-ls1.com/misc/gearing_revision_2.xls

If you have a tranny you would like me to add, post the gear specs and I'll add it.

Added RPM vs MPH in 100 rpm increments. Put your info in the first page labeled "Top Speed"

 

4l60e - 3800 converter - 4.11's - 28" tire

 

Put your figures in the blue box's and it will do the math for you. Leave converter loss 15% if your not sure of what it really is..

 

I was going to ask how I might calculate converter loss?
Nice job on the spreadsheet.

 

Pretty sweet!

 

I found on the top end my 3,200 fuddle has about 10% loss.. You could data log rpm and mph if you hav HP tuners. Don't use the dyno's info though as it didn't show the same loss as the real world..