Maximum speeds in each gear? (5-speed)

[camaroincal]

My speedometer doesn't work in my '88 lx 5.0 5 speed manual. I have 2.73 gears and I'm just wondering at or around what speed am I going at the redline of each gear? My guess is 45 mph in 1st, 75 in 2nd, and 105 in 3rd?...What about 4th and 5th? I would like to know from someone with a speedometer who knows exactly. Thanks.

Also one more thing on my mind. I realize the 2.73's aren't so great performance wise compared to 3.27's +, but I've been wondering since my car is a 5 speed, what is the shortest gear you can have that allows you to stay in 3rd gear through the end of the 1/4 mile without having to shift to 4th?

[MagicRat]

You can work this out mathematically. Its quite easy.

4th gear is a 1:1 ratio, where the driveshaft spins the same RPM as the engine.
5th gear is, as I recall, 1:0.7, so the engine turns at only 70% of the driveshaft speed.

Choose your maximum safe engine RPM and calculate your driveshaft speed in each gear.

Divide the driveshaft RPM by 2.73 and you get the rear wheel RPM.

Multiply that RPM by 60 and you get the tire revolutions per hour.

Measure the circumference of your rear tire and you can work out how far your car travels for each revolution of your tire, in feet.

Multiply that by the tire revolutions per hour.

Divide that number by 5280 and you get miles per hour.

[camaroincal]

Yikes! You want me to do math!?!? Well only half kidding. I appreciate that you posted that. Maybe when I'm not so tired I'll try to figure it out! =P

[SkylineUSA]

Cars and math go hand in hand, but if your lazy you can use www.speedworldmotorplex.com/calc.htm