I tried again, it won't work if you put in zeros for the gears.
Anyway the small block 350 has a red line of 5500 but I doubt it would ever hit that in top gear so I put in 4500. It says 123 MPH which I think is reaonable for a mostly stock 350 with 2.73 rear end and factory spec tires. I tried 4800 and it showed 131 MPH, I don't think so. The fastest I ever saw on the speedo was a tick over 115 MPH and I lifted off so 120 or so would be it. If I had an optional 3.42 rear end top speed would be about 106 MPH.
My 300 HP Cadillac Deville Northstar comes up with 148 MPH and I believe it. Again the most I've ever seem is 112 MPH but the on ramp to the 404 was ending and I had to brake to merge with traffic.
Pretty cool to play around with.You can also figure out how fast your travelling just before you shift by inputing you trans gear ratios for a certain rpm.Keep in mind that if you have an auto trans , your rpm will be around 5% higher at any given speed due to converter slip.
good question! I am usually too scared to look down!!! ha ha how about 5500? My 66 Corvette Coupe 427-425 would "show" 152 mph at 5500 x 3.55 gears P225/75R-15 Yokohamas on 15x8 's It would go 85 in second and 115 in third...that was in '74