Dinan 4.10 LSD

Sticky · 10-20-2008, 04:53 PM

Quote:

Originally Posted by PencilGeek

RPM isn't in there. It's MPH vs. Torque.

It wasn't easy to collate the data on MPH for each FDR because at a given RPM, the speeds will be different. You can't just plot the same data points for each gear because then the wheel speeds wouldn't be aligned properly. I couldn't figure out how to make the Excel 'collate' option work to do this. So that was the hard part -- aligning the data. I had to write a simple visual basic program in excel so do it...probably could have done it with excel statements...but the VB approach was only a couple of minutes.

Does anybody still want this for DCT...or is there enough data here that it's a moot point now?

Hmmm, why not graph DCT stock 3.15 vs. 3.62? Would be interesting to see vs. the manual 4.10

T Bone · 10-20-2008, 05:16 PM

Sticky, Lucid from personal experience, I have lined up with an M6 with the stock 3.62 rear end versus my 3.91 Dinan rear end. I would pull significantly the other M6 in 3rd and 4th gear (didn't go much higher).

Clearly my car is not 8% faster, it is somewhere in the middle as Lucid suggests.

Also, the 3.91 and 4.10 ring & pinions are BMW Motorsports gears.....so you will be able to get them into the M3 diff.

Sticky · 10-20-2008, 05:41 PM

Quote:

Originally Posted by PencilGeek

Doing this takes quite a few hours of my time. That's why I asked how much interest there was in such an endeavor. If you're the only person asking...sorry, I can't justify my time for that -- especially considering the nature of the discussions we had on the RPI thread. I've made the spreadsheets available for download. You could modify them but it's not going to be easy. Aligning the MPH between two FDRs on the same gears with 6250 data points per gear wasn't easy to figure out...and comparing 6-speed to 7-speed could be a complete nightmare. To compare 6-speed to 7-speed, you'd probably have to write some significant amounts of visual basic code to figure out which data points to throw away and which ones to keep...or do some type of piecemeal approach to data collection. At least with 6-speed vs. 6-speed, there were the same number of data points per gear -- and it was just a problem of aligning (or duplicating) certain datapoints to make the MPHs align. 6sp vs 7sp won't be easy...but I think it can be done (as I'm trying to think of possible solutions as I type).

I wouldn't waste a few hours on it, I don't expect you to.

Sticky · 10-20-2008, 05:42 PM

Quote:

Originally Posted by T Bone

Sticky, Lucid from personal experience, I have lined up with an M6 with the stock 3.62 rear end versus my 3.91 Dinan rear end. I would pull significantly the other M6 in 3rd and 4th gear (didn't go much higher).

Clearly my car is not 8% faster, it is somewhere in the middle as Lucid suggests.

Also, the 3.91 and 4.10 ring & pinions are BMW Motorsports gears.....so you will be able to get them into the M3 diff.

Yes, so this should carry over for 3.62 as well.

I have personal experience with the Dinan 3.91's vs. 3.62, I know how it plays out in practice.

lucid · 10-20-2008, 06:10 PM

Quote:

Originally Posted by PencilGeek

OK, here's some comparisons based on my own dyno charts with 6250 data points per gear ratio.

PG, something is off with your calculations/graphs. The car with the modified final drive initially shifts earlier than the stock car, but with vehicle speed, it actually starts shifting later than the stock car. That is not possible. It should shift even earlier with increasing vehicle speed since it has the modified final drive. See the trend in the graph I posted earlier in this thread.

JMD0977 · 10-20-2008, 06:50 PM

Quote:

Originally Posted by PencilGeek

I'll also re-run the 6MT based on actual dyno results, and post it. I'll also provide the spreadsheet.

In fact, I'll do four graphs for you guys:
1) Stock 91 octane, 6MT, 3.85 vs. 4.10
2) Current dyno, 6MT, 3.85 vs. 4.10
1) Stock 91 octane, DCT, 3.15 vs. 3.62
2) Current dyno, 6MT, 3.15vs. 3.62

The most interesting one would be:
Dct 3.62 Vs 6MT 4.10
So that us Dct guys know what to expect from a 6MT 4.10 .
I wonder if 3.91 would be too much for Dct.

Sticky · 10-20-2008, 07:15 PM

Quote:

Originally Posted by JMD0977

The most interesting one would be:
Dct 3.62 Vs 6MT 4.10
So that us Dtc guys know what to expect from a 6MT 4.10 .
I wonder if 3.91 would be too much for Dct.

I would think 3.62 is already pushing it at 13%, 3.91 would be ~20%, top speed would go down to 166 instead of 180. The gears with 3.91 would just be way too short and fuel mileage would be atrocious.

JMD0977 · 10-20-2008, 09:23 PM

Quote:

Originally Posted by PencilGeek

Doing the 6MT vs. DCT would be a nightmare for data alignment. I just don't have the time for it

From your earlier post, I knew you would say that, but I had to try.

Quote:

Originally Posted by Sticky

I would think 3.62 is already pushing it at 13%, 3.91 would be ~20%, top speed would go down to 166 instead of 180. The gears with 3.91 would just be way too short and fuel mileage would be atrocious.

Yeah, I agree. I'd probably get tired of it sooner than later.

bigjae1976 · 10-20-2008, 10:33 PM

Quote:

Originally Posted by Sticky

Ask him the if the ring and pinion will fit the E92 diff housing.

Actually, I think they might be looking for an M3 to use as a guinea pig to find this out. Dan also mentioned that a 3.45 might be the way to go with DCT.

Sticky · 10-20-2008, 11:49 PM

Quote:

Originally Posted by bigjae1976

Actually, I think they might be looking for an M3 to use as a guinea pig to find this out. Dan also mentioned that a 3.45 might be the way to go with DCT.

Eh, forget the 3.45, 3.62 FTW.

I don't know where they are located but when I go to evosport to check up on my cars progress I'll start dialogue on the diff with them.

What I am worried about is the DCT auto mode changing based on speed instead of rpm. This was an issue with the SMG going to shorter gearing, the car would not upshift at WOT.

footie · 10-21-2008, 01:49 AM

Your graph shows what I was about to say might happen in a race against the two.

That is the stock car would lose early on in each gear though would come back at the other near the end of each gear but ultimately the lose early on would be too great to overcome and would steadily fall back with each gear change until about 5th gear went things would balance out and the gap stopped increasing.

Strax · 10-21-2008, 05:52 AM

Very good work! The graphs illustrate my real world experience.

The shorter gear car has the advantage until it shifts to the next gear and then the longer gear car has the advantage until it shifts too. But because the shorter gear car has the advantage for longer, it ends up accelerating faster.

Sticky · 10-21-2008, 10:55 PM

I spoke to evosport today regarding the gears. We will have to wait and see if the E92 diff is similar to the design of the E46 diff. If it is, we can just pop in the ring and pinion and this will be an amazing bang for the buck upgrade for DCT people.

I should have more info tomorrow, but the possibility is good.

mrp310424 · 02-13-2010, 02:09 PM

Quote:

Originally Posted by e46e92love

Tell me about it........so many punk kids buying this car for all the wrong reasons. What would posses a parent to buy their kid a 70k sports car. Its not even the money, its the common sense of putting a young kid behind the wheel of a sports car. Just blows my mind.........but I digress, sorry for going OT.

I bought this car to track, not to drag. Way to stereotype though. :rolls:

10-20-2008, 05:16 PM	#68
T Bone Brigadier General 530 Rep 4,021 Posts Drives: 2008 335xi Coupe Join Date: Feb 2007 Location: The land where we kill baby seals iTrader: (0)	Interesting thread...... Sticky, Lucid from personal experience, I have lined up with an M6 with the stock 3.62 rear end versus my 3.91 Dinan rear end. I would pull significantly the other M6 in 3rd and 4th gear (didn't go much higher). Clearly my car is not 8% faster, it is somewhere in the middle as Lucid suggests. Also, the 3.91 and 4.10 ring & pinions are BMW Motorsports gears.....so you will be able to get them into the M3 diff. __________________ "Aerodynamics are for people who cannot build engines"......Enzo Ferrari
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10-21-2008, 01:49 AM	#77
footie Major General 1094 Rep 8,013 Posts Drives: i4M50 Join Date: Oct 2007 Location: No where fast iTrader: (0) Garage List 2022 BMW i4M50 [0.00] 2020 BMW M5 Competi ... [0.00] 2008 E92 M3 [0.00]	Your graph shows what I was about to say might happen in a race against the two. That is the stock car would lose early on in each gear though would come back at the other near the end of each gear but ultimately the lose early on would be too great to overcome and would steadily fall back with each gear change until about 5th gear went things would balance out and the gap stopped increasing.
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10-21-2008, 05:52 AM	#78
Strax Enlisted Member 0 Rep 40 Posts Drives: E46 M3 Join Date: Dec 2007 Location: Athens, Greece iTrader: (0)	Very good work! The graphs illustrate my real world experience. The shorter gear car has the advantage until it shifts to the next gear and then the longer gear car has the advantage until it shifts too. But because the shorter gear car has the advantage for longer, it ends up accelerating faster. __________________ www.bmw-motorsport.gr
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10-21-2008, 10:55 PM	#79
Sticky Banned 78 Rep 2,244 Posts Drives: E92 Jerez DCT M3 Join Date: Jan 2008 Location: Anaheim Hills / Malibu iTrader: (0)	I spoke to evosport today regarding the gears. We will have to wait and see if the E92 diff is similar to the design of the E46 diff. If it is, we can just pop in the ring and pinion and this will be an amazing bang for the buck upgrade for DCT people. I should have more info tomorrow, but the possibility is good.
	Appreciate 0 Quote