Rear diff question - Page 3

gsfent · 28th December 2008, 18:36

Quote:

Originally Posted by blueaudis4

I had a carbon build up as my car was an earlier build date. When I had it cleaned and fully dismantled I had the engined bored slightly and put in a bit bigger pistons and a specially built schrick camshaft. Forged psitons and valves and titanium spring were used. A thicker seal (headgasket was used) I haven't put the headers on which is literally the only thing I am missing and the reason for that is I wanted to do a bit of research between the Dinan and the SuperSprint. Also have been looking into Jet hot for coatings of the headers for thermal efficiency. I know my engine is lacking the breathing part for the exhaust gases. Once I figure out a set the engine should have both more torque and more hp. Its incredible to drive right now. I have driven an S2 and this kills it by far currently. Haven't been in an S3 which I am sure is incredible in itself. If you have any data or experience with either the super sprint or dinan headers let me know. I have been also debating on whether or not to upgrade to the Dinan diff 3.45

Who did your ECU work?
Regards,
Jerry

CNS Racing · 29th December 2008, 18:26

Quote:

Originally Posted by blueaudis4

Trying to do some research between our stock rear differential and the upgrade that Dinan sells. What are the pro's and con's between the two?

Hello blueaudis4,

We are pleased to announce our NEW CNS Racing E39 M5 3.62 High Performance Differential Kit which is now available!

http://www.cnsracing.com/product.sc?categoryId=13&productId=38

http://www.m5board.com/vbulletin/1475535-post2.html

" *** We offer the best price for the E39 M5 differential upgrade! A core charge of $600 is included in the price of the order which will be refunded upon return of the owner's OEM Differential. The CNS Racing Differential upgrade comes complete with everything you need for $1999 plus shipping!

The shorter 3.62 gearing takes advantage of torque multiplication lowering the stock 3.15 ratio for a 14.9% increase in torque delivered to the road. The improved acceleration comes with only a minor increase in engine speeds at cruise and no effective reduction in top speed potential.
The CNS Racing 3.62 Limited Slip Differential delivers the greatest ''bang for the buck'' in terms of improved and more immediate acceleration from the E39 M5."

Thank you,

CNSracing.com

rneedham1979 · 29th December 2008, 21:48

Sounds good! Maybe even beter with a 15% m5board discount....

Ryan

Quote:

Originally Posted by CNS Racing

Hello blueaudis4,

We are pleased to announce our NEW CNS Racing E39 M5 3.62 High Performance Differential Kit which is now available!

http://www.cnsracing.com/product.sc?categoryId=13&productId=38

http://www.m5board.com/vbulletin/1475535-post2.html

" *** We offer the best price for the E39 M5 differential upgrade! A core charge of $600 is included in the price of the order which will be refunded upon return of the owner's OEM Differential. The CNS Racing Differential upgrade comes complete with everything you need for $1999 plus shipping!

The shorter 3.62 gearing takes advantage of torque multiplication lowering the stock 3.15 ratio for a 14.9% increase in torque delivered to the road. The improved acceleration comes with only a minor increase in engine speeds at cruise and no effective reduction in top speed potential.
The CNS Racing 3.62 Limited Slip Differential delivers the greatest ''bang for the buck'' in terms of improved and more immediate acceleration from the E39 M5."

Thank you,

CNSracing.com

slimmbones · 31st December 2008, 04:39

Didnt someone on the board use the gear set 3.45 from a M3 with no problems and cost less?

rneedham1979 · 31st December 2008, 04:51

I think it is 3.62 in the M3. I believe that is what CNS uses. To do it yourself, you will need a large amount of BMW shims or the ability to make customs shims, certain tools and the know how.

Buy one already assembled with a warranty, it is worth the money

Ryan

Quote:

Originally Posted by slimmbones

Didnt someone on the board use the gear set 3.45 from a M3 with no problems and cost less?

phillym5 · 31st December 2008, 05:26

Quote:

Originally Posted by rneedham1979

I think it is 3.62 in the M3. I believe that is what CNS uses. To do it yourself, you will need a large amount of BMW shims or the ability to make customs shims, certain tools and the know how.

Buy one already assembled with a warranty, it is worth the money

Ryan

Like mine!!!!!

rneedham1979 · 31st December 2008, 12:13

Exactly

Quote:

Originally Posted by phillym5

Like mine!!!!!

slimmbones · 31st December 2008, 18:52

On Bekkers website they have a 3.45 Oem gearset for the M5,has any installed this gear set?

mikeoski · 31st December 2008, 19:09

Quote:

Originally Posted by blueaudis4

I have driven an S2 and this kills it by far currently. Haven't been in an S3 which I am sure is incredible in itself.

What do you mean kills it?? A car length? Maybe less? What kind of power you making at the wheels? Have you done a side by side comparison of an S2 and your whatever you are calling it?

We like hard facts on this board....

Happy New Year All!!!

rneedham1979 · 1st January 2009, 03:10

No it doesn't!

An overbore of a few mm's adds maybe .1 to .3 of a liter and it does not equal much more power, your cams (normal shrick, not custom) does not add much more power either.

Yes, everything work nicely together and yes, i am sure it has more power than stock but... without headers you are not making 30-40 whp over stock. Its just not happening, the stock exhaust manifolds will not allow great gains due to the restrictive small size.

I agree 100% with the previous poster, we like hard facts and proof. How about a dyno sheet? Drag slip... something.... Maybe even the S2 owner you raced....

Oh and just FYI, the highest RECORDED naturally aspirated WHEEL HORSE POWER has been Dinan S2's. A few of them were 400+whp and most are around 380+WHP...

Ryan

Quote:

Originally Posted by blueaudis4

I have driven an S2 and this kills it by far currently. Haven't been in an S3 which I am sure is incredible in itself. If you have any data or experience with either the super sprint or dinan headers let me know. I have been also debating on whether or not to upgrade to the Dinan diff 3.45