NEED ADVICE ON GEARS!!!
Thread Starter
Melting Slicks
Joined: Jan 2002
Posts: 2,784
Likes: 3
From: Atlanta GA
NEED ADVICE ON GEARS!!!
I must have posted a question about this about 5xs now and still dont have a great answer.... On 89 6-spd Corvette, what are the best gears to throw in the rear end for performance, but still will allow me to cruise a 80 all day??? I have been told 4.10s.... If so, how much time would they take off a Stock 89 6 spd Vette 1/4 time by themselves???? Thanks Guys
P.S. In 6th Gear, what RPM would i be at with 4.10s cruising at 80MPH???? :chevy
P.S. In 6th Gear, what RPM would i be at with 4.10s cruising at 80MPH???? :chevy
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
Re: NEED ADVICE ON GEARS!!! (StealDads67)
My LT4 at 80mph in 6th gear is turning about 2100-2200 RPM. The 4.10's are a very managable gear for all around driving and actually make 6th gear somewhat useful! In terms on 1/4 mile times, I'm really not sure...have to wait for someone else to answer that one.
Drifting
Joined: Mar 2001
Posts: 1,636
Likes: 3
From: Lafayette IN
Re: NEED ADVICE ON GEARS!!! (StealDads67)
I must have posted a question about this about 5xs now and still dont have a great answer
P.S. In 6th Gear, what RPM would i be at with 4.10s cruising at 80MPH???? :chevy
MPH = (RPM * TD * pi) / (GR * TR * 1056)
where:
MPH-Miles per hour
RPM-Revolutions per minute
TD-Tire diameter in inches
pi-3.1415926...
GR-Rear gear ratio
TR-Tranny gear ratio (4th on a 6 speed is usu. 1:1)
1056-Constant that takes care of inch-mile and minute-hour conversions
For tire diameter, tires are rated like 255 50ZR16
where
255-(SW) sidewall width in millimeters
50- (AR) aspect ratio
16- (WD) wheel diameter in inches
TD = [([(SW) * (AR/100)] * 2)/25.4] + WD
So for your case,
RPM = (MPH * GR * TR * 1056) / (TD * pi)
What did you come up with?
[edit] forgot to add the mm to inch conversion in tire calculation
[Modified by HighHopes85, 12:55 AM 2/17/2002]
