Rear diff question - Page 2

PJS · 27th December 2008, 18:46

I have the dinan diff and the only drawback is a short first gear... I would absolutely do it again.

someone has to say it: it is the poor mans supercharger

M5CCIE · 27th December 2008, 18:52

yeah, although I'm seriously considering the ESS SC kit.

I wonder if the 3.45 would still be ok with a SC or would I need to go back to stock.

phillym5 · 27th December 2008, 19:19

If any of you guys are interested.... I have a fully Koala built 3.64. It will handle well over 800 hp. Comes in the case.... no need to swap out internals... or leave a core deposit. Ready to ship.....and bolt right in.

markm5Ireland · 27th December 2008, 19:26

Stupid question but is 0-60 and 0-100 times quicker than stock? If so what are the times?

Anyone in Ireland or UK gone the Dinan Diff route?

markm5Ireland · 27th December 2008, 19:33

Also How much is it, for Diff and then fitting?

DRM · 27th December 2008, 19:51

Quote:

Originally Posted by markm5Ireland

Stupid question but is 0-60 and 0-100 times quicker than stock? If so what are the times?

Anyone in Ireland or UK gone the Dinan Diff route?

'Not a stupid question. In my experience, lower diff gearing (3:45) allows better times to 60/100 from time saved on shifting (one less shift needed to get to those speeds; so how much less time is dependent on your individual driving skill), as opposed to any power increase. That said, lower diff gearing torque multiplication makes the car "feel" like it has more power; which is what most folks enjoy about it.

After getting my car S/C'd, with 625hp/505 lbs torque, 'switched back to stock 3:15 diff from Dinan's 3:45. That much increased power/torque rendered 1st/2nd gear almost useless; 'didn't like having to concentrate so much on shifting before rev limiter bounce. 'Just my perference. Another S3 owner I know kept his 3:45 diff, 'cause he likes faster acceleration coming off tight, low gear turns. But he's a pro driver, and I'm not.

Edit: Less shifting to specific speeds, with a 3:45 diff, also means you'll need after market software to raise rev limiter by ~250 RPM's. 'Don't think you can source Dinan's software in Ireland ('Suggest you call Dinan and ask), but suspect European tuners offer this feature in their product - it's pretty standard with most tuners.

DRM · 27th December 2008, 20:21

Quote:

Originally Posted by markm5Ireland

Also How much is it, for Diff and then fitting?

Dinan price for 3:45 diff swap is $2700 (and you have to send them back your stock diff to avoid a $1800 "core charge"). Dinan currently has a 15% rebate offer ('till 2/28/09); so diff cost would be $2295. You're in Ireland, so your local shop would do the swap; and the cost is whatever you can negotiate.

There'd also be to/from shipping charges involved (Dinan's charge to ship new diff to Ireland, and your shop's cost to ship your stock diff back to Dinan).

Here's Dinan's website with all details: 5 Series*::*M5 (E39) 2000-2003*::*Driveline Tuning*::*3.45 Limited Slip Differential

'Hope this helps.........

markm5Ireland · 27th December 2008, 21:26

DRM - Thanks for all the info,

rneedham1979 · 28th December 2008, 18:17

Bored and stroked engine? Please explain.... I haven't heard of any stroker cranks for the S62 or much luck with a punched out S62 without sleeves.

No headers?

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? I believe the stock diff can attain a higher top speed? What are the tops speeds to both? What are the 0-60 and 61-100 and 101-150 times? Is there any cooling benefits either through cooling fins or a larger rear diff oil capacity? Have seen a few board member that have them and are changing back to stock what are your reasons? My upgrades include schrick cams, software, bored and stroked engine with all internals replaced, upgraded racing clutch and flywheel, zionsville heavy duty M5 radiator, Pss9's and a SS race cats, xpipe and eisenman race exhaust. This is a daily driver that gets driven the way an M5 should be driven. What speeds can be attained in 1st 2nd and 3rd gears? Overall is it worth the money or does it get old quick? Lastly are there any other options aside from going with Dinan?

blueaudis4 · 28th December 2008, 18:28

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