E28 M5 Unichip Results

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   I first met Piers nearly 2 years ago at our first dyno day we arranged for some E30 guys. He brought along his stunning E28 M5 and power was 280.4bhp and torque was 244ftlbs. As the car has some Hartge tuning bits and bobs added to the engine, including some Shrick's we thought the figures seemed a little low, however, I have had a few other M6's on the dyno which at best only made 260bhp, so maybe 260bhp is all you can hope for from the 24v 3.5 engine instead of 286 as quoted from BMW? Another power run before the conversion was carried out proved dyno and the M5's consistancy with 280.6bhp and 244ftlbs and 279bhp and 243.5ftlbs respectively.
Either way, after a fair bit of discussion, mostly recently, after looking into all other options including stand alones, Piers decided to go with the Unichip and have me do the work.
Before... 

So, Carbon air box modified to fit the RHD M5 as it was designed for the LHD where the header tank, etc is on the other side of the engine bay. Piers did not want to take an angle grinder to the bracket which is welded to the inner wheel arch which held the AFM and header tank in place. So all modifications are totally reversble. Unichip also installed and ready for mapping...

While mapping, it was clear that the gains we were getting were extremley impressive. Between 40-50bhp was gained on alot of part throttle sites and the change in engine note while I was mapping the car was very satisfying to say the least.
The Results...

And the raw dyno data with a comparison of the before power run imediately before work was carried out and after I finished mapping...

As you can see, upto 1750rpm we have significantly more power at the wheels than we had at the flywheel before. From there right upto 4250rpm we have the same power at the wheels or more than at the flywheel before. The trend continues to 5250rpm.
Torque is also vastly increased over the entire rev range and coule do with the limiter being raised another 500rpm or so, but who knows how safe these engines are upwards of 7500rpm?
So, a massive 50+ftlbs of torque increase over standard at 1500 rpm and a peak raise of around 22ftlbs and an impressive 30+bhp gain at 7200rpm with a peak gain of around 27bhp. 
As the car was running rich in standard guise, we managed to improve the fuel consumption also. Piers averaged 5 mpg more on his journey home at the same speed as he drove down to me at. So thats around 20% fuel saving too. More power, More torque and better fuel economy as well. On road test the car felt very throttle responsive and I was also able to iron out the vast majority of the very jerky on/off throttle these cars suffer with in traffic and slow cruising speeds. All big bonuses.
Obviously some of this was due to the CF air box and the AFM removal as these are as restrictive on these cars as they are the E30 M3. The same conversion can be done on the M635CSi too 

Edited by SHEPSM3