Well did the deed yesturday
After fitting a Simota induction kit recently
I decided to get the car a full fluid change ( including diff oil) at my local indie before a remap. I had intended getting the valve clearances done but the indie insisted it would be a waste of money as the car sounded fine. He reckoned he could tell if they needed doing and mine did not. I was a bit sceptical as there is no record of them being done for some years and the car has done 80,000 miles. I wanted it spot on pre dyno and remap but in the end he was quite insistant that I would be wasting my money so I went with his advice.
I decided to take the car to Evolve in Luton (where I got the indiction kit from). They are a 3 hour drive from me (alright 2
) but I had heard good reports about them and they have featured in lots of the mags for their remaps / mods on BMW's.
The drive down gave me a chance to "benchmark" the Z on motorway cruising. I've only done a few hundred miles in the car since I got it so I was looking forward to the 350 mile round trip.
I found Evolve no problem and spent 2 hours there whilst they dyno'd a benchmark, remapped and re dyno'd.
There where some surprising results.
I had read that you can expect c 300-310 BHP from a stock ///M S50 (against BMW's claimed 321BHP) and so I was expecting /would have been happy with 290 - 300 BHP from my 80,000 miler.
The pre remap dyno showed 324.5 BHP
This seemed to really surprise the guys from Evolve compared to other cars they have done. I brought into question if the car had been remapped already but they confirmed it had not when the backed up the existing mapping. Also the car came with really extensive history and I'm sure any paperwork confirming a previous remap would have been there.
I have no benchmark pre induction kit fitting but there is a really good article in the months (marked as May I think) BMW performance mag. They have just got a Zm Coupe same year as mine as a staff car and their first mod is the Gruppe M induction kit which is very similar to the Simota. They where astounded to confirm a 10BHP increase from the induction kit alone
Net result seems that I have a "spot on" S50 engine and my indie must have been right not to touch it
This then brought a dilema as I could not really expect the remap to push the BHP much further with an otherwise stock engine. But I did not want the remap for a BHP increase but more to optimise the power through the revs.
I sat around for 45 min whilst they backed up my existing mapping and set up and uploaded the remap.
Friendly set of guys there (you could spend a fortune listening to the mods they can do). I looked over a silver ///M Coupe they had in from Europe. A guy had driven it over,left it with them, flown off to China on business and was collecting it in a few weeks after some extensive mods.
Anyway time for the post remap Dyno.
I had already read that it can take 100 miles or so after for the car to Re learn and optimise its settings (I have also been told this by dealers as well after picking up new cars).
So Evolve ran 6 post remap dyno runs. Each one produced slight increases resulting in a cool 331 BHP
. We agreed that 6 runs had pushed the car enough for one day and I was more than happy with that result (with maybe a little following my return motorway trip
Now I'm no expert in these power graphs so I'll post them up for comment.
After seeing these pre remap results I am certain that the extra "kick" I could feel after I fitted the induction kit was real.
The journey on the way back was superb to say the least. The remap may be subtle and is hard to put into words. It is definately noticable on the motorway in 5th gear. There is an extra "urgency" and no hesistancy as you squeeze the pedal and pass a car that has pulled across at a speed that I would normally kick down. Of course you can still do that but the feeling is so much more silky with that induction wine when you can just leave it in 5th.
Once I got off the motorway nearer to home the response seemed a little more brutal and definately more responsive. There is more of a kick in the back rather than a shove and I remember thinking I'm so glad the rear diff has been strengthened as the rear end not so much squats down but almost feels to bottom out under hard acceleration
To say I am chuffed is an under statement
Graphs I don't understand, real world driving I do and in direct comparison the car feels a lot more responsive.
Would I recommend the remap, damn right I would. Get the induction kit as well but make sure your engine is sorted first. You can really feel the added "brutality" from the remap which must benefit from that extra airflow.
I would also recommend Evolve. They are not the cheapest (or the most expensive) but they are used by people far more experienced than me and you know you are getting a tried an tested product from them
Here is the before and after graph
Some piccies on the dyno
A little video