[widetyres]

I did some tune comparisons a couple of weeks ago of Stage 2 maps on my OG M2.

The car is pretty much FBO, but without a cat-back exhaust or intake – it is running an Akropovic Sports Cat (HJS 300), do88 intercooler (similar in size/weight to CSF), Forge charge pipe, NGK 97506 plugs, plus the tune.
All the tunes were run on Shell V-Power 99RON - technically this is probably 92.5AKI (as I believe that the UK fuel has a MON of 86) which is ever so slightly less than PTF/BM3 advise for the “93” map, but it’s the best readily available forecourt fuel we have in the UK, and is supposed to be an excellent standard of fuel. I also have friends with other makes of car putting down ~700bhp on this fuel alone (e.g. no meth).

The results for the stage 2 maps are as follows:

MHD Stage 2+ 93/98 = 429.1bhp
BM3 Stage 2 93/98 = 421.6bhp

MHD also has noticeably more torque, which is very much felt on the road.

However, there is a curve ball to throw into this – the BM3 Stage 2 91/95 map!

Ever since my initial Stage 1 tune (with BM3) I really haven’t been convinced by the PTF 93/98 maps when using UK V-Power; on stage 1 93/98, I recorded 25 knocks in <10 mins of driving – PTF advised that the octane in my fuel (always UK V-Power 99RON ) wasn’t good enough, and kindly gave me the 91/95 map to try – this was massively better and the torque was excellent (still with V-Power). (Great service/support from PTF as usual!)

Moving onto Stage 2, whilst I didn’t have any knock issues with the initial BM3 OTS 93/98 map, seeing as I had access to all the BM3 maps for the M2, I tried the 91/95 variant – again, the low-down torque felt massively better without a seeming loss of top end, so that it what I stuck with.

It appears that my butt dyno wasn’t actually that far off! – the BM3 Stage 2 91/95 tune recorded 431.3bhp!!!

This is pretty much exactly what I would expect for these mods.

These results do prove what a versatile engine the M2 N55 is; with different tuning strategies (MHD run higher boost but less timing advance, and BM3 run slightly lower boost but more aggressive timing) the engine puts out near as damn it the same output – absolutely brilliant!!!

Recommendation for UK Stage 2’ers (but perhaps this extends to the rest of Europe as well???):

Whilst the BM3 Stage 2 93/98 map clearly works well in other areas of the world with different fuels, in the UK you should not be running it as it has noticeably less torque and power.

With the others (MHD 2+ 93/98 and BM3 2 91/95), saying one is more powerful than the other is like splitting hairs; they are so close and within expected/accepted dyno variances of each other (particularly relevant here as the car was taken off in-between).

Which one you go for I think depends on your driving preference and how you want the engine to work for you; on the road, MHD’s extra low-down boost does give it a bit of an edge when lower in the rev range (e.g. <4.5K), but BM3 offers more of a NA experience with power continuing to be delivered closer to the red line (see the power curves past 6K in plot).

If you are in the BM3 camp already then the choice is a no-brainer (just switch to the 91/95 map!!!), but (for new Stage 2 tunes) MHD deserves consideration and it will come down to the “lower boost kick” vs “NA feel towards the redline” feel you prefer, balanced with which tune offers you the features you need.

What am I running now? I was tempted to keep the MHD tune for the extra kick of boost (which I think particularly benefits the manual car to help reduce post shift lag during road driving), but the difference was only slight and I really like BM3’s cold-start target revs customisation feature (MHD does support cold-start disable, but currently not cold-start target revs customisation – although I think that this will now be on their roadmap! 😉 ). So for now, I am running the BM3 91/95 map (but with 99RON fuel!!!).

Logs for the runs are available here:

BM3 Stage 2 91/95: https://www.bootmod3.net/log?id=5f40...729b58b8d0d361
BM3 Stage 2 93/98: https://www.bootmod3.net/log?id=5f40...729b58b8d0d35e
MHD Stage 2+ 93/98: https://www.bootmod3.net/log?id=5f40...729b58b8d0d386

Key for dyno plot:
1) Black = BM3 Stage 2 93/98
2) Red = BM3 Stage 2 91/95
3) Green = MHD Stage 2+ 93/98

Further points and observations:
- The runs were done in this order: 1) BM3 93/98, 2) BM3 91/95 (immediately afterwards, with adaptations reset), then 3) MHD 2+ 93/98 (taken off for the remapping, then put back on ~1 hour later, but ambient temp and air pressure were still the same) - all with the same tank of fuel/hardware etc.
- MHD logged high PSI on the dyno (18.5psi!), but I only recorded a max of 17.2psi when using Sport+ on the road. Still though, on the road, MHD felt slightly torquier/keener low down compared to the BM3 maps.
- In my experience, BM3 generally doesn’t do well in hot weather as IATs climb, and this is most likely due to their more aggressive timing advance strategy that requires cooler IATs and lots of octane to support – my M2 (exactly as above mod wise, with same fuel, but with OEM plugs) only posted 363bhp when the ambient was 83f/26c and IATs rose to 125f/46c (this was at a different dyno, and obviously the heat was a factor that the tune can only do so much to compensate for, but I also don’t think the guy there allowed enough low load running before the actual pulls to help cool the IATs). I cannot comment on how well MHD handles high IATs, but did see that they state in their release log that this is something they have actively tried to improve, and certainly with less aggressive timing this should be the experience.
- BM3 91/95 is running ever so slightly richer than the other maps
- The initial AFR spikes for the BM3 maps aren’t anywhere near as pronounced in the Lambda logs, so I don’t think that these are of concern.
- MHD runs a lower fuel target (2160psi) vs BM3 that is seeking 2450psi (fortunately, I seem to have a strong fuel pump and both were met easily)
- I tried a good handful of MHD tweaks that needed reflashes and there were 2 x failures; this required me to disconnect the battery for ~20mins and then try again – it was fine flashing when following that sequence.
- Somewhere on the forum there was a suggestion that the MHD 102RON map works fine with V-Power 99; please ignore this as it doesn’t; I tried it briefly and the engine at idle and low revs/load felt very rough, so stick with the 93/98 map if you go the MHD route (when using V-Power).
- The dyno plot is showing crank HP, rather than WHP.

WT

[detroitm2]

Thats a pretty generous dyno. What does a stock M2 run on it?

[widetyres]

Originally Posted by detroitm2

Thats a pretty generous dyno. What does a stock M2 run on it?

Not sure on a stock M2, but it's ~379whp (given 12% transmission loss), which is about right for the mods from other UK dynos I've seen.

[detroitm2]

Originally Posted by widetyres

Not sure on a stock M2, but it's ~379whp (given 12% transmission loss), which is about right for the mods from other UK dynos I've seen.

Ah. The dyno readings are giving BHP vs. WHP. that makes more sense.

[i531m]

Great write up and info, many thanks for doing this, Surrey Rolling Road uk is a great dyno
and classed as a heartbreaker, im running MHD so great to see it doing as quoted

have you done any 100-200 dragy times too

[squixs]

I'm also interested in the 100-200 times.

[widetyres]

Originally Posted by i531m

Great write up and info, many thanks for doing this,
have you done any 100-200 dragy times too

Originally Posted by squixs

I'm also interested in the 100-200 times.

I don't have Draggy unfortunately

[Daleb]

Interesting to see the differences.

I’ll try and get 100-200 times for the 95 map. On the stage 2 98 map Mine done 100-200 in 8.7s however I haven’t had any issues with fuel quality or knock when logging and doing these runs.

As a side note I’ve been running the 98 stage 2h map on stock turbo with no issues on v-power. Similar timing and a little more boost/load over the normal 98 map.

[widetyres]

Originally Posted by Daleb

Interesting to see the differences.

I’ll try and get 100-200 times for the 95 map. On the stage 2 98 map Mine done 100-200 in 8.7s however I haven’t had any issues with fuel quality or knock when logging and doing these runs.

As a side note I’ve been running the 98 stage 2h map on stock turbo with no issues on v-power. Similar timing and a little more boost/load over the normal 98 map.

Interesting to hear that another map option is available - I would love to get a bit more boost on BM3.

How did you get access to the 2H map? Did you buy the standard N55 pack? I can't see it as an option in the M2's OTS map pack.

Re the 98 map, you may not get any recorded knocks (I don't), but instead see timing back off slightly in the high revs - you can see on my car that at 5.7K (on the BM3 93/98 map) the timing backs off and the power drops as a result.

[Daleb]

Originally Posted by widetyres

Interesting to hear that another map option is available - I would love to get a bit more boost on BM3.

How did you get access to the 2H map? Did you buy the standard N55 pack? I can't see it as an option in the M2's OTS map pack.

Re the 98 map, you may not get any recorded knocks (I don't), but instead see timing back off slightly in the high revs - you can see on my car that at 5.7K (on the BM3 93/98 map) the timing backs off and the power drops as a result.

You have to request it, it isn’t available through the map pack. I need to test the 100-200 on this map also to verify if it isn’t in fact quicker.

Yeah I noticed your timing was much cleaner on the 95 map. I personally haven’t really had the issues you have had with timing.

https://www.bootmod3.net/log?id=5dcc66b5c090c64aeaab311e

One of the last logs I took for that map.

[widetyres]

Originally Posted by Daleb

You have to request it, it isn’t available through the map pack. I need to test the 100-200 on this map also to verify if it isn’t in fact quicker.

Yeah I noticed your timing was much cleaner on the 95 map. I personally haven’t really had the issues you have had with timing.

https://www.bootmod3.net/log?id=5dcc...90c64aeaab311e

One of the last logs I took for that map.

Thanks - I've contacted PTF.

What time of year did you do that log? - your IAT's are super low (nearly half of mine) and that will definitely help keep the timing advanced. I'm guessing it must have been in winter, perhaps almost freezing outside?

If not, then your I/C is doing a much better job than mine! Please can you let me know what mods you are running?

Cheers.

[Daleb]

Originally Posted by widetyres

Thanks - I've contacted PTF.

What time of year did you do that log? - your IAT's are super low (nearly half of mine) and that will definitely help keep the timing advanced. I'm guessing it must have been in winter, perhaps almost freezing outside?

If not, then your I/C is doing a much better job than mine! Please can you let me know what mods you are running?

Cheers.

I can’t remember but going off of the IAT’s it isn’t summer. Don’t often log in the winter just due to conditions.

It’s a VRSF 5” HD IC, works very well and only rises a few degrees on multi gear pulls. Also ran it on my m135i so I’ve had a fair bit of time and testing with it.

Engine wise I have VRSF I/C, decat, FTP charge & boost pipes, panel filter, pure turbo inlet v3 and bm3.

I’ll try grab a log of this 2h map on v-power and I’ll post it up.


Edit: just to add in the past I did have an issue with fuel quality at a shell petrol station. It was fairly quiet, now I try and use busy stations.

[AmuroRay]

Awesome work - question though. Does MHD have Stage 2 + or is it just Stage 1 and stage 2?

And do you have the wheel hp graphs?

[meady100]

I'm no expert but how about the 95ron map is giving more torque, due to running rich, due to you testing it straight after having reset adaptions? Surely an exact like-for-like is needed for the testing conditions between 95 & 98? You on Insta? Mine is @dunstablem2 would love to chat more as I'm also running BM3 stage 2 Manual!

[widetyres]

Originally Posted by AmuroRay

Awesome work - question though. Does MHD have Stage 2 + or is it just Stage 1 and stage 2?

And do you have the wheel hp graphs?

Thanks for mentioning - I had forgotten that MHD have a 2 & 2+. It was the 2+ that I used - I have updated the original post to reflect this.

Sorry, no WHP, just the BHP graphs.

[widetyres]

Originally Posted by meady100

I'm no expert but how about the 95ron map is giving more torque, due to running rich, due to you testing it straight after having reset adaptions? Surely an exact like-for-like is needed for the testing conditions between 95 & 98? You on Insta? Mine is @dunstablem2 would love to chat more as I'm also running BM3 stage 2 Manual!

I'm sure that you are right - would have been the fairest I guess. The 98 map did have adaptions reset, but ~20 miles before at home.

I don't think though that it would have made much difference; I have believed for some time that the 98 map wasn't as powerful (at least on my car at any rate).

[Daleb]

Stage 2h log on v-power. It’s about 18/19 degrees outside today.

https://www.bootmod3.net/log?id=5f5b...0b4331561d0eed

[widetyres]

Originally Posted by Daleb

Stage 2h log on v-power. It’s about 18/19 degrees outside today.

https://www.bootmod3.net/log?id=5f5b...0b4331561d0eed

Nice - I bet that feels pretty strong.

I contacted PTF but they won't give me the 2H map - perhaps their policy has changed - they said that the engine is different enough that they won't allocate it to an M2. I really doubt that (given the declared M2 N55 differences and that you are running it), but they said the only way to get a map close to it was to put in a custom tune request.

[Daleb]

Originally Posted by widetyres

Nice - I bet that feels pretty strong.

I contacted PTF but they won't give me the 2H map - perhaps their policy has changed - they said that the engine is different enough that they won't allocate it to an M2. I really doubt that (given the declared M2 N55 differences and that you are running it), but they said the only way to get a map close to it was to put in a custom tune request.

It feels pretty good, top end still feels held back and I think there's some room for improvement with no hpfp restrictions. I'm wanting to fit a HPFP upgrade especially with the new rumoured stage 2+ OTS maps coming out for bm3.

Right I see, obviously changed their stance on it. maybe due to the up and coming stage 2+ maps? The map looks to run 1-1.5 psi more than the stage 2 98 map with similar timing. I still haven't tested the 100-200 on this map to see if its actually quicker on the road over the stage 2 OTS. From my experience and testing, riding the HPFP limit will result in slightly slower times and this is towards the limit for my car. It certainly fells good on the road though.

[VisualEcho]

Originally Posted by widetyres

Ever since my initial Stage 1 tune (with BM3) I really haven’t been convinced by the PTF 93/98 maps when using UK V-Power; on stage 1 93/98, I recorded 25 knocks in <10 mins of driving...

It's reading things like this that make me not even want to tune my car.

[3t3p]

Thanks for this WT.

I'm thinking about stage 1 even when I am FBO as of Monday as I'm a bit chicken.

Is the same above applicable to BM3 stage 1? I.e in the UK it's better to use the lower octane map?

Cheers

[widetyres]

Originally Posted by 3t3p

Thanks for this WT.

I'm thinking about stage 1 even when I am FBO as of Monday as I'm a bit chicken.

Is the same above applicable to BM3 stage 1? I.e in the UK it's better to use the lower octane map?

Cheers

It was for me with Bm3. Haven't tried mhd stage 1.