rear end gearing

I have two s12's
one is an 85 with the ca20 rear end gearing
the other is an 87 with ca18et rear end gearing
i bought the 87 because it had a sr20 already in it and turbo goodies and was a good price.
but the chassis is not great
i plan on swaping the sr20det into my 85 with the ca20e rear ended car
both are irs open diff
what i want to know is does anyone have this motor with either rear end and how is the top speed
my speedo has never worked in either car so i dont know what to expect

anyone????

same gearing 4.11

sr20 with turbo gearing
that is approx 210km/h ish @ around 5200 - 5300 rpm

nice job on the dash
i am in the works of doing the same thing hope it turns out like yours