Anyone running 4.10 differential?

[JazzM]

Please post your experiances with this modification.

I'm debating between 3.73, 3.91 and 4.10. How is the drivability impacted with the 4.10? In 6th what is the rpm at 60-80 mph?


Thanks,

T.

[Rollaway]

Please post your experiances with this modification.

I'm debating between 3.73, 3.91 and 4.10. How is the drivability impacted with the 4.10? In 6th what is the rpm at 60-80 mph?


Thanks,

T.

I posted the same question on roadfly. I was told that 80mph w/ a 4.10 was about 7500rpm in 6th.

EDIT: I ment 3500rpm in 6th sorry

[JazzM]

In 5th or in 6th? Can someone confirm this?

Thanks,

T.

[Mik3 Agby]

7,500 RPMs at 80 mph in 6th gear? :eek is that possible?

[M3 2 NV]

I have a 4.10 and it is the way to go. I believe 90mph in sixth is at 4000rpm. The car pulls great but second comes and goes real quick

[Dave04M3]

7,500 RPMs at 80 mph in 6th gear? :eek is that possible?

Thats actually in 3rd gear, as 8K rpm in 3rd gear is actually around 90mph where the 3.62 OEM ratio is right at a 100mph. There is only a 250 rpm increase for every jump up from 3.62, so a 4.10 setup would really only be a 500rpm increse to reach the same speed as the oem ring and pinion. Dave.

[Dave04M3]

Please post your experiances with this modification.

I'm debating between 3.73, 3.91 and 4.10. How is the drivability impacted with the 4.10? In 6th what is the rpm at 60-80 mph?


Thanks,

T.

You can forget about the 3.73 ratio as that gear is much to close to the OEM gear that you would never notice it. In fact revs would be within a 150rpm of the OEM ratio of 3.62. If you are going to shell out the money I would say go with the 4.10's. Granted your 0-60 time would be off a bit but your 0-100 and 1/4 mile times would be smoking if you could launch with all that torque multiplication. Do some 4.10's and run some D/R's out back and it would be a nice combo for the M3 with the excellent traction the car gets off the line. You would have to worry about axle hop though. Sometimes gears can exaggerate this problem. Dave.

[M3 2 NV]

Thats actually in 3rd gear, as 8K rpm in 3rd gear is actually around 90mph where the 3.62 OEM ratio is right at a 100mph. There is only a 250 rpm increase for every jump up from 3.62, so a 4.10 setup would really only be a 500rpm increse to reach the same speed as the oem ring and pinion. Dave.

I'll check later on when I take her out for a drive.

[Markus]

where can you buy a 4,10 or a 3,91 ?

Markus

[AndrewM3]

where can you buy a 4,10 or a 3,91 ?

Markus

You can pickup a 3.91 or a 4.10 from Mo at Kinetechnik - Go to www.Kinetechnik.com - shoot them an eMail or give them a phone call, tell them Andrew sent you.

Yours truely,
Andrew

PS: Mention your a Bimmerforums member.

[Kevlar]

I plan on calling Mo to get a 3.91 for myself... 4.10 is too aggressive in my eyes.

[Irrenarzt]

4.10 is too aggressive in my eyes.

I just sold my 3.91. 4.10 is the better choice without a doubt. Go 4.10, you'll thank me later. The 3.91 yielded only barely noticeable feel in pull.

[MAB Badgerbimmer]

The boys at Fall-Line Motorsports, who will be installing my 4.10, also tell me that if you spend alot of time on the track with a 4.10 you should do a diff cooler as the 4.10 runs alot hotter than the 3.62.

[M3 2 NV]

Alright guys, just got to work and 4th tops out at 200km/125mph.

[NoSoup4U]

M32NV -

How do you like the V700's? Ever try the RA1's? Trying to figure out which one to go with next year. I'm leaning to RA1's b/c good rain tire as well and can drive on the street with them.

Also anyone --

How much is the 4.10/3.91 LSD?

Did everyone here get std. lockup at 25% or did you go for 40% lockup?

What is installation time and cost?

TIA

[flipm3]

how much does top end suffer with the 4.10?

[Kevlar]

w/ a 3.64 you can theoretically go 201mph ... w/ a 4.10, you're probably limited to about 180 ish if memory serves me correctly.

[M3 2 NV]

The V700's are great but I have nothing else to compare them to.

I have standard lockup with my 4.10 and it works fine. Install for me was 0 because I did it myself and all the parts required will total around $1200. The length of the removal, gear swap and install does take some time. I have done this 3 times and I still need a weekend to do it. Most of the underside of the car must be removed (I have found a way around this) to undo the driveshaft.

[M3 2 NV]

w/ a 3.64 you can theoretically go 201mph ... w/ a 4.10, you're probably limited to about 180 ish if memory serves me correctly.

Right and 3.91 is 190.

[jajja]

I plan on calling Mo to get a 3.91 for myself... 4.10 is too aggressive in my eyes.

i have 3.91... Not worth it if you ask me..

i am going up to the 4.10.. i honestly don't feel much at all.. 7% difference.. nothing major...

[M-Phibian]

I'm debating between 3.91 and 4.10 myself. I'm ready to buy now, but I'm really torn between the two. I was originally *positive* I wanted the 4.10. But since I plan on getting a power-adder down the road (S/C), I believe the 4.10 will be much too short with the extra RWHP. Talk about excess wheelspin! So I'm thinking the 3.91 will be a good, balanced ratio for both applications. It will work well with the extra power a supercharger will provide but will also give me some good gains with my current power right now. Thoughts? (Translation = help me make up my mind please)

[jajja]

I'm debating between 3.91 and 4.10 myself. I'm ready to buy now, but I'm really torn between the two. I was originally *positive* I wanted the 4.10. But since I plan on getting a power-adder down the road (S/C), I believe the 4.10 will be much too short with the extra RWHP. Talk about excess wheelspin! So I'm thinking the 3.91 will be a good, balanced ratio for both applications. It will work well with the extra power a supercharger will provide but will also give me some good gains with my current power right now. Thoughts? (Translation = help me make up my mind please)

my 3.91 might be goign for sale soon.. PM me...

[Dave04M3]

I'm debating between 3.91 and 4.10 myself. I'm ready to buy now, but I'm really torn between the two. I was originally *positive* I wanted the 4.10. But since I plan on getting a power-adder down the road (S/C), I believe the 4.10 will be much too short with the extra RWHP. Talk about excess wheelspin! So I'm thinking the 3.91 will be a good, balanced ratio for both applications. It will work well with the extra power a supercharger will provide but will also give me some good gains with my current power right now. Thoughts? (Translation = help me make up my mind please)

Heck I would probably just stay with the 3.62's if you are going with a huffer. I would do the huffer first, see how much traction you get in 1st and 2nd and then decide wether or not you even need the gears. Dave.

[Kevlar]

The boys at Fall-Line Motorsports, who will be installing my 4.10, also tell me that if you spend alot of time on the track with a 4.10 you should do a diff cooler as the 4.10 runs alot hotter than the 3.62.

Hmmm... diff cooler needed, never thought of that

[Irrenarzt]

Diff cooler may be important in Florida. I guess you might be better off with the 3.91 after all.