What is the best diff to use for drifting M5 Or M3

[warren g]

Best diff for drift

[Teaguer]

Really depends on what engine/trans/mods and tire size you are running.
Also its about finding the right gear ratio NOT what the donor car is.

Tell us what eng/trans/mods/tire you have and we can steer you in the right direction.

[Sagaris]

check out http://www.diffsonline.com/

The question is somewhat difficult to answer, both M5 and M3 diffs are clutch-type limited slip units which is what you would want for drifting. The ratios and % lockup are going to depend a lot on your driving style and what kind of corners you are sliding around. Tire selection is important too since too much grip/not enough power makes it hard to break traction while too little grip means you spin easily and do not have forward propulsion.

[warren g]

CAR-E30 318/ENGINE-SR20 TURBO/TRANS-GEAR BOX\TIRE-17-205-45.
Thanks. the car s a buddy of mine thank for the help.

[Wanganstyle]

best diff for drifting is the one the driver can control.

no stock m3 or m5 will be good for drifting, its not setup that way.

M5 diffs also don't fit into 3 series. they are all 210mm since the beginning (e28m5). e60m is even BIGGER (new v10 is a 230mm)

[Ian Bowers]

3.73 puts wheel speed right around 60mph at 7100rpm in second.

Where are you sliding? What speed are the corners?

[warren g]

3.73 puts wheel speed right around 60mph at 7100rpm in second.

Where are you sliding? What speed are the corners?

Am sliding on back roads and on the track. So the 3.73 will be a good start to go with?

[warren g]

Really depends on what engine/trans/mods and tire size you are running.
Also its about finding the right gear ratio NOT what the donor car is.

Tell us what eng/trans/mods/tire you have and we can steer you in the right direction.

CAR-E30 318/ENGINE-SR20 TURBO/TRANS-GEAR BOX\TIRE-17-205-45.
Thanks. the car s a buddy of mine thank for the help.

[Wanganstyle]

so about 2400 lbs weight
200-250 rwhp from close to stock stock SR20?

the Sr20 has a 5 speed transmission with overdrive-

1st gear is: 3.321
2nd gear: 1.9
3rd gear: 1.3
4th gear is 1:1 ratio
5th gear is super overdrive at 0.759

OEM pairs in the S13 body with a 4.08 final drive differential.

compare to a G260:
1st gear: 3.83
2nd: 2.20
3rd: 1.40
4th: 1:1
5th : 0.81 (overdrive)


if you compare to an e30 with standard g260 and 3.73 final drive, you can see that the Nissan gearbox is a little longer ratio- for 1/2nd gear this is because the Sr20det is a TURBO engine, turbo engines want longer loads - also for traction (turbo cars have more % torque part throttle than NA from turbo loading)

I graphed this:

transmission 1: stock Sr20det nissan with 4.08 final drive
transmission 2: Stock e30+G260+3.73 final drive.



Then I graphed this:

Transmission1: Sr20+nissan 5 speed + 3.73

transmission 2: Stock e30+G260+3.73 final drive.



if the goal is to setup close to original Sr20det as possible, then your friend should fit the 4.10 final into the e30. 3.73 will be longer gearing than stock sr20det is used to (4.08).


With turbo cars+ drifting i like LONGER gears. Make more torque and spin tires with the torque, hang out in powerband longer to spool turbo.

NA cars need to get to power max and don;t care about loading, so shorter gears may help depending on course.

if you are sliding 3/4th gear often and engine torque produced is low for breaking tires free then perhaps bump the ratio to a 4.27-