Tuning my E46 M3 part II - The tuning

[johann]

If you haven't read Tuning my E46 M3 part II, read that first at http://www.bmwm5.com/vbulletin/showt...threadid=12382

After what felt like an eternity I finally heard from Kelleners 6 days after getting home. Volker Stark at Kelleners Sport called me December 6th and also sent an email with the results of the first dyno run. The temperature was 19 degrees Celsius and the air pressure was 1013kPa. My car turned out to have 310rwhp@7400rpm and 386.5Nm@5000rpm before tuning.

By measuring transmission losses during coast down, the transmission loss measured was 34.1hp and by using a conversion factor that takes temperature and air pressure into account all this would equate to 343.4 flywheel hp. This would mean that transmission losses would be only 10%. That sounds a bit on the low side in my opinion.

Many others claim that you can’t trust the transmission loss estimate from a dyno and that 10% transmission loss is way to low. Instead the following formula could be used on rear wheel driven +300hp cars: Flywheel hp estimate=(rwhp+10)/0.88. Applying that formula on my car would mean that my bone stock M3 had 363flywheel hp. Sounds a bit much, doesn’t it?

On the other hand 310hp is what some E39 M5s have had on dynos. Anyway, what really counts in real life is rwhp and now we had rwhp value on the stock car that could be compared to the dyno result after the car had been tuned, at least if circumstances such as temperature were somewhat similar.



Well, flywheel hp are interesting if you want to compare you car with manufacturers hp claims since they always are flywheel hp. Also, they are useful from a bragging point of view.

Next time I heard from Kelleners was on December 11th, my birthday. : Now camshafts, air filters and ECU tuning was in place. Volker told me the car gained 20hp and the top torque was now 404Nm, that’s almost as much torque as the Nowack N400 gets when running on Shell Optimax fuel with 99+ octane RON (94 in US). My car was running on 98octane RON (93 in US).

I was expecting a little bit more but Volker told me to wait and see because the catalysers and exhaust was still to be installed. I guess the total package is more than just the sum of its parts.

Next time to hear from Volker was December 13th. Catalysers and exhaust had been installed and the ECU had been tuned accordingly. It now had 28 more hp than stock but there was a drop in power between 4500 and 5500rpm. Kelleners wanted to work more with tuning the ECU to get rid of that power drop. This would mean that there was no point in me flying down the 14th, which was the original plan since the car wouldn’t be ready. I was a Cheap Charlie when booking the flight, my plane ticket wasn’t refundable nor could I use for another flight but since I could get more power in my M3 that meant less than nothing.

We set a new date, preliminary this time. I would fly down early Wednesday the 19th to pick up my car. Volker called me on Tuesday 18th and did he have some good news! The car now had 38hp more than stock. The drop in power curve was gone and max torque was now up, no to 404Nm but at least to 400Nm. It seems like it pays off to work a little bit extra on the ECU tuning, maybe something for Dinan to consider?

I called my travel agency and had them schedule the first flight to Düsseldorf the following morning. The flight would departure at 6:30 and it was supposed to be blizzard. This was a flight I didn’t want to miss so I booked a cab to pick me up at 4:45!! I called Volker and told him that I would arrive at Düsseldorf 8:30 so he could be there with my M3 to pick me up.

Since bad weather was on the way to Germany, Denmark as well as in Sweden and I still had summer tires on the M3, my plan was to leave Kelleners before lunch and try to get home before the blizzard hit me. That meant that I had no need for much in terms of clothes, just a fresh shirt, and a pair of socks and some underwear in case I had stop for the night. Packed a small bag and I was set.

When it was time to go to bed I was all too excited to fall a sleep so I just spent some hours surfing the web, maybe not too clever when you have a 1500km drive the next day. But if you can’t fall a sleep, what can you do? I had to get up at 4:00 and all of a sudden the clock was 3:00 I realized that if I went to bed now, I would most likely oversleep and miss the flight so I kept on surfing the web one more hour. I then took a shower and shaved, got dressed and had some breakfast.

I went down to the cab and it drove off for the airport. Guess what? There was no snow so I got to the airport really quick. Checked in and went to the SAS lounge to get some coffee but it wasn’t open yet. I tried to find an open coffee shop or a bar but nothing was open except a magazine stand. I bought an issue of a Swedish car magazine, Automobil, not my favourite magazine but it had a test drive of the Lamborghini Murcielago.

I went back to the SAS lounge and realized it now was open and to my surprise they had a really nice coffee machine with espresso, latte and cappuccino. Now what does a guy who hasn’t slept in all night except some 30 minutes in a cab? A double espresso off course! I drank the coffee and started reading the article about the Murcielago. I soon realized why this wasn’t my favourite Swedish car magazine.

I boarded the flight and fell a sleep at once , to no surprise, and didn’t wake up until we hit ground in Germany. I was the first one out of the flight and since I was travelling light with carry-on only, I had no luggage to wait for so I was out of the “passenger zone” at once.

I called Volker and asked where too meet. After trying to locate him for a couple of minutes I call him again and we realize we are on separate floors. He was on floor below me, where you usually get out if you have had luggage to claim, which I hadn’t. I went down to his floor and met him at once. I wonder how we solved things like this before we had cellular phones. I for one can’t remember.

We went to the garage where my M3 was waiting. As soon as I started it was clear that the exhaust note had a much deeper and throatier sound and that the engine was revving much faster than before. This was very nice! I could help myself opening the window and revving the engine while driving to the garage exit.

Volker told me about a resonance problem at 1700rpm and it was there indeed, not too bad though. It could go away after a while Volker promised that if it didn’t they would replace the exhaust. We left the garage and headed for Autobahn.

Surprisingly there were no morning rush traffic and on the Autobahn on-ramp I floored the car in 2nd. Wow, it felt so much better than before and I almost hit the rev limiter since it was revving much better and didn’t feel restrained above 7500rpm any more. Shifted to 3rd, revved to redline, shifted to 4th, 5th and 6th and stayed below 220km/h since it was raining. The exhaust note at higher revs was fantastic. Check here for some sound samples: http://www.bmwm5.com/vbulletin/showt...threadid=12054
I had been driven the M5 exclusively for some weeks and even compared to the massive power in the M5, the M3 felt really strong.

Compared to the feeling with winter wheels on the M5, the M3 felt so much more nimble and agile. I think the lowered springs had something to do with that. Anyway the new anti-roll bar was not installed yet since it was delayed from the supplier.

We soon got the Kelleners Sport in Dinslaken. We had coffee and started to walk trough the dyno graphs. To my surprise I realised that it was more than 38 new hp, it was 42 fresh rwhp, a total of 352rwhp@7390rpm! The max torque was 400Nm@5820rpm. This may sound a bit high but the torque is above 350Nm from around 2100rpm and until almost 8000rpm. Who needs a turbo to get a flat torque curve? The temperature during the dyno run was 24C and air pressure was 1034kPa, both a bit higher than

Measuring transmission losses during coast down now indicated a loss of 33.7hp and with conversion factors this would add up to 380 flywheel hp. Using the formula instead would give (352+10)/0.88=411 flywheel hp! :



Since I was eager to get away we quickly finished the paper work, said good bye and I left for Sweden.

To be continued.
/Johan

[MAVERICK]

Whether it's 380hp or 411hp at the flywheel, either of these numbers are impressive. You now have the same power as the N400, but at a lesser price and at lower rpm. Now, you need to race an N400 to see which car is better.

[Gustav]

Good job, Johan and Kelleners!

Let's by a 10 hairdryers, mount them on a stick, conenct them to the car 12 V and drive up and down the roads to get rid of the snow

[johann]

Originally posted by Gustav
Let's by a 10 hairdryers, mount them on a stick, conenct them to the car 12 V and drive up and down the roads to get rid of the snow

Good idea!

[Mr. Grinch]

Great post. Thanks johann!

[johann]

Originally posted by Mr. Grinch
Great post. Thanks johann!

Thank you!

Cheers,
/Johan

[SkodaRS]

are you a regular visitor to events like brostugan, and like thos...?

[johann]

Originally posted by SkodaRS
are you a regular visitor to events like brostugan, and like thos...?

Not regular but sometimes I'll go there.

Cheers,
/Johan

[johann]

Originally posted by MAVERICK
Whether it's 380hp or 411hp at the flywheel, either of these numbers are impressive. You now have the same power as the N400, but at a lesser price and at lower rpm. Now, you need to race an N400 to see which car is better.

Good idea!
I am off for autobahn now, se ya!

Cheers,
/Johan

[Mr Janne]

This is a really good story!! Great post, Johan!! Can´t wait to read part 3

[Mr. Grinch]

The other nice thing, depending on your point of view, is that the components used in this upgrade are much closer to stock than the Nowack kit. So not only is it cheaper to buy, but should be easier and cheaper to maintain over time as well.

Sounds pretty interesting.

[johann]