in the sticky about the gears i read that 4.10 gears dont really make much difference in track time, they just make the car feel faster. im my thinking, shouldnt the faster reving make the car quicker off the line or from a first gear roll? if it does help, how much?

 

it will make the car quicker, i think you misread or misunderstood. 4:10s will launch your car and defiantly lower your times, also depends on how the driver drives the car.

 

after i reread the post i realized he was talking about an a4 w/ a high stall converter..... my bad guys. i got too anxious when i read it and didnt read it too clearly

 

So a converter won't make it faster, only feel faster?

Damn I guess I wasted my money!

 

4.10's will also get the chassis up to wheel speed quicker.... which will promote better traction.

 

I dropped half a second on a stock car when i went from 3.23's to 4.10's

 

chicane- can you explain your comment and relate it to launching?

 

Simply stated (if I can actually pull that off)...... Let me try to put it this way, and tell me if it makes sense or not.

Think of two identical chassis with the only difference being the ratio in the rear differential. Car "A" is using a 3.08 ratio and car "B" is using a 4.10 ratio.

Both cars launch at the same time with the same power and the same traction. Both cars then at the same time with the same power... loose traction. Within that, if you were to take a snapshot of the engine speed vs wheel speed vs chassis speed at the time the chassis broke traction.... you would see that car "A's wheel speed would be faster than car "B"..... just from the mechanical ratio alone. It is an instantaneous value.

Or in other words.... when you had 3.08's in your car and you lost traction, you could spin the wheels till the cows came home. But with 4.10's..... it seemed to 'come back' to you sooner and it would recover and hook up again.

When you brake traction with the 3.08's.... the rate at which the tire will accelerate is much faster than with the 4.10's. The way it promotes better traction is that it allows you to get the chassis up to wheel speed quicker if you were to brake traction. The tires wont 'run away' due to the difference in the instantaneous rate in wheel speed.

A shorter gear is eaiser to hook and will do it faster while allowing the weight to transfer without the wheel speed getting away from you. It pretty much is eaisly viewed to why drag racers typically use gearsets in the 4.88 to 6.50 range.

Running a higher ratio will also allow the engine to accelerate to get you into the power band and keep you there in your shift recovery point.

Hope that babble helped out some how.

 

So what im understanding is 2 cars same tires and rpm launch both will spin like mad but whereas the 3.08 will continue to spin or spin longer the 4.10 will start to bite even if you dont let off the gas hook and go also if when each hooks the 4.10 will recover from the bog down quicker and will accelerate faster.

 

The 4.10 ratio will hook up faster due to the chassis speed catching up to the wheel speed sooner.

"The bog". You guys kill me. I take that as being the same as "coming out of the hole" ??

If you have the means to pick up the June '06 issue of Circle Track and racing technology magazine, there is an article on "Advanced Gear Ratio Technology".... which gives you the skinny on what we are talking about. Not being up for plagiarism, I will try and read it a few more times and throw down a better explaination.

 

really, its simple.

on a M6 car, gears really really help.

in a auto car, they dont help nearly as much as a stall.. and if you get the stall, gears have a minimal effect. the point of gears is to stay in the powerband coming out of the hole... but the converter has already done that for you, so the helpful effects are minimized... on a street/strip auto car, you'll have a minimal gain from gears when you ahve a stall, but a large effect on MPG since you dont have the same double overdrive as a M6, and your RPM is higher when under lockup.