Hello guys!
I am new here. New in terms of posting, but been reading various threads for a long time. Finally decided to join and participate. AND, to ask for help. Help for how to solve the ECU tune for 288 280 Schrick std lift cams for mine 2006 Z4M coupe.
Before that I plan to write here a short history of tuning. It might be interesting for you guys to read about my experiences, especially because I also have one more S54 powered car, the lovely M3 E46 coupe in CSL silver color.
In 2012 I bought both cars as excellent condition low mileage cars. Z4M coupe had 34 tkm, now 45tkm. M3 had 42 tkm, now 89 tkm. M3 E46 is supposed to be a slightly modified daily, and it was for 5 years – how much pleasure it has given me – always makes me happy and puts a smile on my face. Now I drive it far less because I want to keep it preserved, and it really still is. With a Superspint street muffler, resonated mid section, decat anti rasp front section and stock euro headers it is just slightly louder, but has a nice tone and extra grunt. There is a tune with CSL rev match, also ESS SMG software, underdrive pulleys.. B12 Bilstein kit just slightly lower than stock, but with both anti roll bars upgraded.. a great and hassle free ride.. love it, love it! A 3.91 diff is the next “smooth” upgrade for M3.
Now, the Z4M coupe has a totally different role, as the character of the car really is different from factory – a beast! A complete TC Kline Racing suspension setup: DA coilovers, cambers plates, camber rear arms, just front thicker bar, geometry.. weight reduction, Supersprint race mufflers (light), forged light wheels, Li battery.. and NA power: Supersprint V1 stepped headers (good gains) with decat oversize front section, air scoop, underdrive pulleys.. a very intensive driving experience – a track focused car driven on the track.
In stock configuration I am sure Z4M has a bit more power than M3 E46 due to the more aggressive tuning from BMW and different ECU and harness (MSS70). I measured everything on the same dyno. Z4M had 300 whp peak power stock. Then with ESS tune got 309 whp, but power increase began only above 5000 rpm – proving how aggressive the tune is from stock. With the “power” button on, it is difficult to drive it smoothly, you guys know that. Adding just Supersrint x-pipe with race mufflers a gain of 3whp - 5whp is evident across the rev range, resulting in 312 whp of peak power.
Here is the dyno graph of stock tune vs ESS tune (showing gains only above 5000rpm):
Here is the dyno showing gains of just the Supersprint x-pipe + race mufflers. Pleasant surprise was it for me:
So, for the next step I was so excited! Supperprint V1 stepped headers with belonging catless first section! Proven from many sides as a great power upgrade. BUT, then first problems started rising.
First drive with same ESS tune shown a lot of issues.. Hick-ups, hesitations between 2k and 4k rpm, as well as torque loss… Only after 5000 rpm the car got power. Had no will to take the car to the dyno. On website ESS was very clear that their tune is not compatible with stepped headers , and they told me the same… so I was in search for another tune. I also tried the stock map and got less hesitations. Following some advice I bought new O2 sensors, no change. Also tried MAF from my M3, no change. So, I bought an Evolve map for V1 headers and decat. It was really better, but hesitations and hick-ups were still there.. If full throttle was applied bellow 4k rpm, it cuts the power. I was unable to do short 2nd gear power slides in city driving, while with M3 it was so easy to slide on bellow 4k revs. Frustrating. But, with the Evolve map the power was really there after 5000rpm. In the meantime I added underdrive pulleys and RPI air scoop. I decided to go on the dyno. And, peak power was 327 whp, but with hesitations evident. Here it is:
Then I met two nice guys (today my friends) who started cooperation with one ECU tuner from Bulgaria – Madness Motorsport, Raychinov is his last name. At first we started by trying some maps just to eliminate the hick-ups and hesitations. And after two attempts, the issues really vanished – what a pleasant surprise! (I was beginning to lose hope, since Evolve was surprised with my issues, and their test tunes never solved the issues.) Then we went for a remote dyno session And the result was 334 whp of peak power without issues! Great! A true 11% of power gain from stock. Here is Evolve (with gentle throttle) vs Raychinov dyno:
With this power, the car was a blast to drive. Starting from 50 km/h up to 290 km/h my front was just a couple of meters away from the back of my buddies stock M5 V10. He was shocked to see me so close on those speeds, since he was used to see cars vanishing in his mirror after 200 km/h. Ok, my car had 40kg less already. The 7 speed SMG has closer ratios, the weakest point of our cars is shifting from 2nd to 3rd gear, when the revs drops too much.
So, issues with using stepped headers on Z4M were evident in my case, but they can be solved. And Supersprint V1 headers give serious gains over euro headers, so it’s worth the hassle.
My buddy also had and still has a stock E92 M3 manual, which is slower than my Z4M, so we went to measure his V8 M3 on the same dyno. While we were at it, the same day a took mine M3 E46 too. (While my M3 is very, very close stock V8 M3, it is even up to 200 km/h and then starts losing a few meters..) Here were the results of peak power:
• Z4M – 334 whp
• E92 M3 stock – 340 whp
• E46 M3 – 312 whp (gentle mods described above)
Here is the graph my Z4M vs M3 V8 stock:
See how close they are! S54 is a masterpiece! Here is the graph M3 E46 vs Z4M:
See what headers do above 6000 rpm. Since that the only difference between the two S54, both are decat, air scoops and have same underdrive pulleys. Ok, Z4M has race muffler, M3 has street version of Supersprint muffler.
THEN …
I was quite happy, and instead of just going for a 3.91 diff for Z4M (which I did later) and continue with weight reduction (Recaro Pole seats and A/C delete) I ordered Schrick 288 280 std lift cams with new Schrick DLC coated rocker arms.
Installation was done nicely, but it did look scary LOL. I was there and followed every step. Did not do any vanos related repairs since the engine is really like new. When I turned on the engine first time after the cam swap, it was just like nothing has been done. No vanos noise on the start up, everything smooth, valve clearance job done, no codes, everything great.
First drive was with the previous custom map from Raychinov. I also ordered the Evolve “cam” map for those cams, just to check it out. I was difficult for me to conclude the power difference from before. The power rise on high rpms was felt, but it can also be due to the loss in lower revs – I know that could happen. Unfortunately the hesitations and hick-ups returned. Before going to the dyno I’ve measured with gps accelerations from 100 to 200 km/h and the car was 0.5 seconds slower. At that time I was thinking: “OK, don’t get upset, Raychinov will make a custom tune for cams and everything will be fine”.
So, we setup a dyno session. We started from the previous (“precam”) Raychinov tune. The car had less power. Here is the graph:
Green is“old” 334whp, blue is cams with same tune, red is cams with evolve cam tune. So above 7500 rpm the power is similar, but there is a 20 WHP POWER LOSS ON 7000rpm ! And, 10 to 15 whp less bellow 6000 rpm. Raychinov started working on the tune and after a couple for tunes we reached 340 whp on 8000 rpm, but on 7000 rpm and bellow the power was increased but still was significantly less than before cam swap. Then he asked for AFR readings, and they were all ok, but he cancelled developing the tune saying he is not ready and is not sure what to do next.
The plan was to get prepared for the next dyno session in some time, but that never happened. He was swearing the Siemens MSS70 ECU on Z4M all the time I remember. He gave up to do that job. So, I was left with a slower car and with hesitations under 4k rpm. Splendid! And that was two years ago!
I then asked Evolve for help. They’ve sent me a few test tunes, but all were similar, with similar slower acceleration times than before and with hesitations. I even tried their alpha-n tune from another Z4M with same cams and there was no power difference, but the hesitations were less. And, with that alpha-n map heel-toe rev matching is not possible – what a frustration that was when I found out.
I contacted TTFS, Frank Smith. It was very difficult to reach them.. I got a reply after some time: “.. we don’t have time to work a proper map for the MSS70 platform..”. What a pity.. So, I got stuck
I’ve been recommended to contact a tuner from Germany – MK Motorsport. They are known for serious NA tuning, they have their own developed carbon airbox. If you check their website you will see they have several stages of tuning for Z4M, including “engine kit C” which contains cams and is advertised with 70bhp gains over stock 343. They also have an “engine kit D”, which is like C + headwork and is advertised with 85bhp gains (15bhp gains on headwork!). So they must know there business. I expressed my concerns due to what I went through, and they consider that job as a “piece of cake”. Finally I bought their map.
And, really, hick-ups were gone. But… what really happens is that a power limit occurs if pushing the throttle beyond a certain point, but that power limit is gentle and smooth. After 5000 rpm I can feel the power is far less. At one point I was driving full throttle on 7000 rpm in 5th gear and when I lift the throttle a short lasting burst of acceleration occurred. After that I was experimenting with throttle positions and the car runs faster if 70% - 90% is applied, with best results when lowering the throttle slowly. Dyno showed the truth:
So, a 50whp peak power drop! I am waiting for the next map. Or next step. I asked for a remote dyno session. We’ll see.
At this moment while I am waiting and don’t sense any eagerness from MK and I am stuck. And worried. Is there anybody out there who went through similar issues and that can give me some advice? Does anybody know who can do the job? People mention EPIC, Randy, any opinion? Guys, help me.
Ok,there is a spare option. In fact, that is the best option, though it is costly. A stand-alone. Plug and play, keeping the stock harness. Emtron KV8. Map sensor. Far, far easier to tune and potential for some additional benefits. I have a friend who does the job. They already did an E30 S54, as well as a E36 S54. They get 2-3 hp on max revs when they open idle valve LOL! They can add DCT from E82 135i or E9x 335i or E9x M3 with adapter plate. Going to do that one day for sure! For track, with DCT is easier to focus on braking and corner entry than with manual.
With Emtron KV8, in the future when I decide to go for a carbon airbox – tuning will be easy and heal-toe possible. Add some even crazier headers – easy to tune. If I decide to supercharge – again easy… Ok, I will lose DSC, but I always drive it with OFF. It confuses me if it’s on.
But, as I said, quite a lot of cost, just to get a tune. Especially if there is a solution using a stock ECU.
Thanks for reading (who had the nerve…
)
Vuki