does any one have an idea of what ratio ive got i run 2300rpm at 55mph? thanks jerry:)

You'll need your tire hieght, then this calculator will help you.

http://www.richmondgear.com/101032.html

Awesome, I just ran a few combinations. Very helpful.

When my 69 12bolt had 307 gear with m20 and approx 25.5-26" tires it was approx 2400-2450 rpm @ 60mph so your 2300 rpm @ 55mph should put you roughly at the same 60mph rpm i was at if you went 5mph faster so you likely have 307-308 gear depending on tire height assuming non od trans.

Scott