Performance Data Of Different Tuning Setups
Ok, it has been about 1 year since I have purchased my E92 M3. Everything about the car is so far so good. I'm very satisfied and happy. In one year, even if it is my not DD, I have done 15K km. My fuel consumption is around 15L/100 km. Done only 1 oil change 12.000 km which is not a scheduled maintanance.
During the last 1 year, I want to have some performance mods other than my BMW Performance seats which were installed in the car before I got the delivery from Germany. So I have bought Akrapovic Evolution exhaust system (from headers to muffler), BMC cotton filter and Evotech software tune. I had some combination of the mods to see the difference. To test the performance of the car with different setups, I did 100 to 200 km/h runs with the same person next to me; measure it with the same equipment (Performance box), on the same stretch of road to make everything equal as much as possible. All runs were done after midnight but there is still temp. variances and maybe wind difference but this is the best I could do. I don't have any performance data of the car when it was bone stock, sorry Smiley So here are the results of different setups:
1- Akrapovic Evolution Exhaust System + stock filter + stock tune
I averaged 10,0 sec for 100-200 km/h runs (w/2 people in the car + 3/4 fuel). The car was running strong and my friend who was sitting next to me told me that his ex-08 M3 Coupe w/6 MT did about 11,0-11,2 sec on the same road. BTW, Akrapovic is, IMO, the best exhaust one can buy for M3 IF he is ok with the sound. The complete EVO system eliminates 2 of the 4 cats which are the primary cats + 2x 100 Cell sports cats instead of 2x200 high flow OEM cats and 2 separate mufflers instead of 1 OEM cat-back. The whole system is titanium and 24 kg lighter than stock. I have seen many dyno of this exhaust and it is on par with what Akrapovic claims: 35 NM more torque through out the rpm range and 20-22 hp peak power. Any downsides? Well, I find the exhaust sound too rough and too loud. It is not so loud for a complete system but I guess I'm getting older and get tired of too much noise. While most of the owners find it quit, I find it loud. It was sad to remove mid-section of the system after using it about 2000 km. Smiley BTW, lack of primary cats triggered my SES after 600-700 km.
2- Akrapovic Slip-on (just the mufflers) + BMC cotton filter + Stock tune
Because of the excessive noise of the complete system, I removed mid-section of the Akra. So I just left with the mufflers which saved about 14-15 kg over stock and according to Akrapovic gives only couple of hp (3-4) on top end. When removed the mid-section, I immediately felt the lost of power/torque in the mid-range (3500 rpm-6000 rpm) I used to wheel spin in 4th gear on a specific road but now only I chirp the wheels in 3rd. However, I was very happy with the mellow exhaust note of the just slip-on. There is now "peace" inside the car. There is less noise on downshifts, too. Also, BMC cotton filter add some intake noise which was too loud for my taste with the complete system thus I removed it when I had the full system. I had used the car with this setup about 1000 km. I haven't done any test runs against the clock but mid ranges of the car was definitely slower.
3- Akrapovic slip-on + BMC + Evotech stage 1
After some searching and reading reviews I decided to go for Evotech software. My friend (who did the test runs with me is a big car nut) is vendor of Evotech and when Oliver the founder of Evotech came to Turkey, I had my car chipped with his software. Normally, my M3 is tuner-protected but he had the codes and download the new software via cable without removing the ECU. Immediately my mid-range power came back. This was the most significant sign of the software. The throttle response was more linear and mid-range torque was more. I haven't felt any power increase at the top end but increased power was there for the rest of the rpm range. Oliver also updated my DKG software with May 2011 release from BMW which improved "1/2 throttle" and "no throttle" midrange downshifts. It is hard to explain it but now the transmission is more responsive even not in the full attack mode. We made the test runs with my friend again. The temp. was warmer (May) than our first test runs (March). We had 3/4 fuel and on the same road we measured 9,9 sec best and 10,0 sec average for the 100-200 km/h runs which was exactly the same with the 1st setup. Now I had the same performance with the full Akrapovic setup without the excessive noise.
4- Akrapovic EVO + OEM filter + Evotech Stage 2
I was very happy with the 3rd setup BUT wondering about the performance of the complete exhaust system with a tune. So, I put the Akra. mid-pipes back on and on the same day (Oliver was in Turkey again) I had Evotech stage 2 tune which was developed for Akrapovic Evo full system in Germany and Oliver told me that this tune will give a little more hp than their other catless-tune @ the top end. So we had another test runs (a week ago, August 2011) with my friend, on the same road, 1/2 fuel in the tank. We clocked 9,3 sec average for 100-200 km/h and 9,0 sec as the best time. The road was different for the 9,0 sec run so we took 9,3 sec which was done on the very same stretch of road as with the other runs above. So full setup yields more than 0,5 sec. Now the car should be around 460hp @8300 rpm (now the limiter is @8600 rpm. Not that I shifted at 8600 rpm but I have 200-300 rpm more before hit the limiter as a safety margin) and it is 1580 kg (with 3/4 fuel and without me).
What am I going to do now? I'm very happy with the setup in terms of performance satisfaction BUT the exhaust noise is too much for me. I try to make myself like the noise but it doesn't help. I will remove the Akra. mid-pipes next month.
I have 2 options to do:
I may just eliminate the primary cats from OEM mid-pipes (like Turner Test Pipes) which will result in increased power over stock system but will cause less noise since the secondary OEM cats are 200 cell (vs. Akra 100 cell) and mid-resonators are larger than Akra.'s Also extra weight of the OEM mid-pipes over titanium Akra mid-pipes resonates less noise.
OR I just leave the mid-section stock, have Evotech tune for stock system and be happy with it.