BMW M5 Forum and M6 Forums banner

1 - 20 of 21 Posts

·
Registered
Joined
·
418 Posts
Discussion Starter · #1 ·
I know these are the two major differentials available. I know of only a few members who have went the Evosport route. A lot more have went with Dinan and there is mixed reviews, some cars have went thru 2, 3, 4 and even 5 different differentials. Any more feedback from owners and anyone switched from Dinan to Evosport or vice versa. I know also Evosport has a few different levels of their differential available also.
 

·
Registered
Joined
·
1,937 Posts
I dont think there have been any problems reported with the Evosport diff, but Dinan had whining issues.
 

·
Registered
Joined
·
418 Posts
Discussion Starter · #3 ·
I know M5Ranger has the Evosport diff and he has only good things to say about it. Anyone else?
 

·
Registered
Joined
·
3,263 Posts
At the time of purchasing the 3.91 diff I had no bias of any kind. I was very early also and there were no complaints out there regarding the Dinan whining issue.
I bought the Evosport diff because, as I was told, Dinan would not sell it to Active Autowerke. They were doing all the work on my M5 at the time of the the mods.
If this is accurate, well those are life's flips and turns.
I am happy for the outcome and the Evosport diff has been a "balls out" performer. Last January when we did a private track rental the M5 did over 25 1/4 mile passes and thank goodness not a single issue handling the stress and added hp.
I congratulate Evosport.
This month we are going back to Moroso.

M5Ranger...Juan
 

·
Registered
Joined
·
158 Posts
I have the Dinan diff, and yeah, there was a whine at first, but it is gone now...or as some like to say, I have selective hearing. I know a couple things about diffs. First, that if you make slant cut gears, you can get rid of the whine. However, slant cut gears are not as strong as straight cut gears...which whine more. So...my conclusion is that Dinan's must be cut more straight than E.S.'s I don't know if that's true or not, but I'm gonna go ahead and make that assumption.

E
 

·
Registered
Joined
·
3,263 Posts
As I've said there is NOTHING weak about the Evosport diff.
I haven't heard of anyone put the Dinan diff through what we did with my M5 plus putting down approx. 580 rwhp with the nitrous.

Cheers, M5Ranger
 

·
Registered
Joined
·
907 Posts
How did your clutch hold up? If I may ask.....how many times have you used launch control? Just wondering as I hear widely varying opinions on how often you can use it before you may experience significant wear on the clutch....

Chris
 

·
Registered
Joined
·
3,263 Posts
The clutch did heat up on one occasion on that night but otherwise everything was solid.
Launch control was not used everytime. It was used on this one.

http://www.youtube.com/watch?v=nG-h1LYdMlE

Cheers, M5Ranger
 

·
Registered
Joined
·
101 Posts
Anyone have any figures for the actual performance improvement from fitting the 3.91 diff. 0-60, 1/4 mile,? Simon Atik mentioned an improvement of about 0.2 seconds on each figure but it would be interesting to hear from someone who has actually documented this.
 

·
Registered
Joined
·
2,066 Posts

·
Registered
Joined
·
101 Posts
Looked at the figures, Thanks.
Wolverine, what mods did you have on the car at the time you posted your acceleration runs with the 3.91 diff in October 2006? Did the Evosport pulley and RPI intakes not come after this? If so what effect do you think they would have on these times, 0.1sec on the 1/4 and 0-60 and 0.15sec on the 55 to 110mph?
 

·
Registered
Joined
·
1,763 Posts
Those are some pretty impressive gains in the 0-60 and 1/4 for this car.

For those who have it, is the diff a must-have mod?
 

·
Registered
Joined
·
1,047 Posts
Anyone have any figures for the actual performance improvement from fitting the 3.91 diff. 0-60, 1/4 mile,? Simon Atik mentioned an improvement of about 0.2 seconds on each figure but it would be interesting to hear from someone who has actually documented this.
It depends on the mods you have. If you have a stock or lightly modded car, I would recommend the 3.91 gearing. If you have a moderate to highly modded car and are looking for the best 1/4 mile times, I would not recommend it.

When I installed my Dinan 3.91 diff, my car was lightly modded and it did improve my times (slightly). After a few more mods I ran into the problem of having to shift into an extra gear (5th) 100 feet before the end of the run which hurt my times. With the 3.91 gearing, the highest trap speed you will see is around 119.5 mph (with an aftermarket 8450 rpm limit). With stock gearing you will see 1 - 1.5 mph more due to the fact you will still be in 4th gear at the end of the run and as you know, 3rd and 4th gear in the E60 M5 are thee gears to be in.

Now, if you have a monster of a car that is on the bottle or something, you are going to be in 5th gear anyway so the gearing doesn't matter as much.


I am going to the strip this weekend with my stock gearing and will compare before and after 3.91 gearing results.


Cheers ///
 

·
Registered
Joined
·
3,886 Posts
Looked at the figures, Thanks.
Wolverine, what mods did you have on the car at the time you posted your acceleration runs with the 3.91 diff in October 2006? Did the Evosport pulley and RPI intakes not come after this? If so what effect do you think they would have on these times, 0.1sec on the 1/4 and 0-60 and 0.15sec on the 55 to 110mph?
I did not have the pulley or intakes at the time. Whether you get the Evo or Dinan 3.91, IMO it is a 'must' mod if you really want to get the best out of the car. The current M5 is geared for the autobahn, using the 3.91 your acceleration improves, at the cost of top-end speed. In the US this is a non-issue.

I agree with 6-speed that if you're looking for the best quarter mile times, you might be better off without the diff, or getting software to increase the rev limit. All my quarter mile times and speeds were after shifting into 5th just shy of the line. That cost me a few tenths and mph for sure.

But if you're looking for the best overall performance, or you track your car, the diff is the best 'bang for the buck' mod I can think of to increase acceleration.
 

·
Registered
Joined
·
2,066 Posts
Perhaps with the ESS software 8500rpm you might be able to avoid the
shift?

It depends on the mods you have. If you have a stock or lightly modded car, I would recommend the 3.91 gearing. If you have a moderate to highly modded car and are looking for the best 1/4 mile times, I would not recommend it.

When I installed my Dinan 3.91 diff, my car was lightly modded and it did improve my times (slightly). After a few more mods I ran into the problem of having to shift into an extra gear (5th) 100 feet before the end of the run which hurt my times. With the 3.91 gearing, the highest trap speed you will see is around 119.5 mph (with an aftermarket 8400 rpm limit). With stock gearing you will see 1 - 1.5 mph more due to the fact you will still be in 4th gear at the end of the run and as you know, 3rd and 4th gear in the E60 M5 are thee gears to be in.

Now, if you have a monster of a car that is on the bottle or something, you are going to be in 5th gear anyway so the gearing doesn't matter as much.


I am going to the strip this weekend with my stock gearing and will compare before and after 3.91 gearing results.


Cheers ///
 

·
Registered
Joined
·
101 Posts
Some marginally larger diameter rear tyres might do the trick to keep you in 4th to the end of the 1/4 without completely offsetting the benefits of the lower gearing.All depends on how important the actual figures are to the individual owner. 0-60mph/100kph and 1/4 mile times provide a recognised comparison with other cars but on the street or track the 3.91 will give you a stronger push in ALL of the gears and just HAS to be worth the "investment".
 

·
Registered
Joined
·
3,263 Posts
My M5 hits 5th gear on the 1/4 mile everytime. On a link posted above showing a video of a 1/4 mile run you can count 5 gears.
 
1 - 20 of 21 Posts
Top