My final gear swap project

[SpeedR]

Originally Posted by 37

Drone can be judged by downshifting to 5th on the highway. Unless you've removed your cats or installed a cheap, obnoxious exhaust then you should be fine.

Have you plotted out the 5.71? It looks WAY too short, even with an auto trans. To closely match a 6MT with 4.67 in gears 1-2-3 you'd need a 4.9. You might only be focused on gears 4-5-6 and missing how short the first three will become. Don't overlook that as it's a major place where a final drive matters.

Realize that the 6AT in this car will have tall 4-5-6 gears no matter what you do. You either need a 6MT if you want all 6 gears spaced shorter or different auto gears. Shortening the first three too much just to shorten the last three means could mean you'll end up with a street car that's undriveable. You truly would be roasting tires and alarming yourself with a 5.71.

Here is a direct comparison of a 6AT + 4.9 (red) with a 6MT + 4.67 (blue): http://www.teammfactory.com/gearcalc...ission+1+%26+2

Take note of what happens at 4th gear. You can't fix that plot with a final drive. You need different transmission gears.

See above. Despite your username, don't go too insane.

I see no problem with the 5.26s on an auto, I think it will be more than drivable and should be a lot of fun with my tires.

Any thing I am missing?

[SpeedR]

http://www.teammfactory.com/gearcalc...ission+1+%26+2

red is auto with 5.26 on 245/40/17s

blue is stick with 4.56 (considered very nice gears for the stick) on OEM tires.

[37]

Originally Posted by SpeedR

Any thing I am missing?

Yes... you're missing a manual gearbox.

5.26 on auto sounds short but isn't far from 4.88 behind a manual. You won't know unless you try. I highly doubt anyone has gone that short on an auto.

[SpeedR]

Originally Posted by 37

Yes... you're missing a manual gearbox.

5.26 on auto sounds short but isn't far from 4.88 behind a manual. You won't know unless you try. I highly doubt anyone has gone that short on an auto.

I know I know this is my first auto ever and its not a bad one at all, but yes all my race cars have had manuals. That being said as a performance driving instructor I can tell you time on track is way more important than Auto vs manual.

If its a real race I ill just go get the SUP. LOL

On a serous note I thanks for your help/input and the links you provided in this thread very good info.

[SmsAlSuwaidi]

Meh, if only we could find a 3.73 diff in good condition right @Frs300?

[Frs300]

Originally Posted by SmsAlSuwaidi

Meh, if only we could find a 3.73 diff in good condition right @Frs300?

Im still looking for just the ring and pinion as well as the entire pumpkin

[SmsAlSuwaidi]

Originally Posted by Frs300

Im still looking for just the ring and pinion as well as the entire pumpkin

If I get desperate about it maybe it might be time for an M82 with a welded diff

[Account Attempt No. 4]

Thanks @PantsDants
I'm a bit late to the party it would seem, but I'm trying to decide between a 4.56 and a 4.88 (from Weir Performance) on an MT for DD (with some tracking)

I was leaning to the 4.88, any input?

[PantsDants]

Originally Posted by Account Attempt No. 4

Thanks @PantsDants
I'm a bit late to the party it would seem, but I'm trying to decide between a 4.56 and a 4.88 (from Weir Performance) on an MT for DD (with some tracking)

I was leaning to the 4.88, any input?

For a DD, I wouldn't go 4.88 with a manual. 65 mph in 6th will have you at ~3200 rpm. If you can live with that and the resulting mpg hit (and potentially increased exhaust drone), go for it, else the 4.56 will still provide a noticeable increase off the line.

As for the track, the gearing you would choose really depends on the track layout itself. Say you're topping out 4th in a specific straight now; if you shorten your final drive, you have to use 5th to go the same speed you were before.