highest mph 1st can do?
4th Gear Member
Joined: Dec 2007
Posts: 1,599
From:
My car will do 40 mph in first gear. In order to hit 60, you would need a lower rear end ratio than 3.31 and really tall tires. Your acceleration would be terrible unless you had a ton of power. I assume this question arises from seeing the z06 vettes and such do 60 mph in first gear. Most cars with 0-60 times under 4 seconds all do 60 mph in first b/c the 1-2 shift adds a good half second.
Thread Starter
2nd Gear Member
Joined: Oct 2008
Posts: 311
From: Oregon
My car will do 40 mph in first gear. In order to hit 60, you would need a lower rear end ratio than 3.31 and really tall tires. Your acceleration would be terrible unless you had a ton of power. I assume this question arises from seeing the z06 vettes and such do 60 mph in first gear. Most cars with 0-60 times under 4 seconds all do 60 mph in first b/c the 1-2 shift adds a good half second.
2nd Gear Member
Joined: Oct 2009
Posts: 337
From: Massachusetts
Top speed in any given gear is a factor of max engine rpm, gear ratio in transmission, rear end ratio and rear wheel diameter (excluding factors such as slippage and wind resistance).
Supercharging, hp, turbo...etc will only effect how soon you get there.
Road & Track data has the 2010 Mustang GT with 5sp man and 3.73 rear topping out at 41mph in 1st gear at 6500rpm in 2.7 seconds.
Supercharging, hp, turbo...etc will only effect how soon you get there.
Road & Track data has the 2010 Mustang GT with 5sp man and 3.73 rear topping out at 41mph in 1st gear at 6500rpm in 2.7 seconds.
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6th Gear Member
Joined: Jun 2007
Posts: 16,182
From: PA to KY ('07) to IL ('09) to MS ('10) to FL ('11)
+1 on a function of tranny, gears, rev limit and tire OD.
With my setup, my top speed calculates at 41.31 MPH at the factory rev limit and 42.97 at my rev limit of 6500.
With my setup, my top speed calculates at 41.31 MPH at the factory rev limit and 42.97 at my rev limit of 6500.
4th Gear Member
Joined: Feb 2008
Posts: 1,465
From: Pensacola, Florida
All numbers are assuming rev limiter @ 6500 RPM, the factory 27.3" tire (235/50/18), and 1st gear of a manual T3650 (3.37 ratio)
3.31 rear gears - 47.35 MPH
3.55 rear gears - 44.14 MPH
3.73 rear gears - 42.01 MPH
4.10 rear gears - 38.22 MPH
You will NEVER see 60 MPH in first gear without hitting the rev limiter first, or destroying your engine. You would require a rear gear ratio of 2.61 before you could hit 60 MPH in 1st gear.
3.31 rear gears - 47.35 MPH
3.55 rear gears - 44.14 MPH
3.73 rear gears - 42.01 MPH
4.10 rear gears - 38.22 MPH
You will NEVER see 60 MPH in first gear without hitting the rev limiter first, or destroying your engine. You would require a rear gear ratio of 2.61 before you could hit 60 MPH in 1st gear.
Last edited by Unleashedbeast; Jun 7, 2010 at 05:31 PM.