Go to Rady's Ring and Pinion Site (Use Google). It has a calculator. Remember, Top gear is 1:1 and your engine is working too hard at 3000 RPM. At a guess, at 2800 RPM (pushing a 216 pretty hard), with a 3.57:1 rear and 30" tires, that's about.....70 mph. That engine would be screaming. Most will try to cruise at 2200 rpm. That gives about 55mph. If your rear is a 4.10 or your tires are smaller, your speed will be lower.
PS Don't trust the speedo unless you know it's the original gearing, and you have original sized tires. If anything changes, the speedo gear has to be changed to recalibrate the speedo.
Good luck! We're counting on you!
Current fleet (subject to change w/o notice) \'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run. My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787. Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.
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