Coupe modifications so far .............Latest update - Severn Tuning ECU Tuning Sessions

[R17SKO]

That’s looks great!!

[1536Z4]

That’s looks great!!

[1536Z4]

I have been in talks with Josh@Severn Tuning https://www.severntuning.com/ since the end of January about getting a tune done for the Z4 after the previous tune I had done left me with a very rich running and at some points in the rev range a not very happy car . The dyno figures looked ok but I just wasn`t convinced they had done everything they could have done as the software program was not working properly . They also only did 3 tunes and that was that .

Josh was a breath of fresh air . He wanted to spend some more time on the N52 engine and I wanted to get the best out of it with my set up so we agreed to spend longer than normal to get it right . Josh had to start by finding a way to unlock the ECU as it had been locked by the previous tuner . He then had to start from the basic stock file and build it up tune by tune . I used his software to datalog the drives around my local roads and then he would work on that data and email me another tune clearing any codes that were produced on the way .The first tune was done on the 7th March and the final tune before dyno which was number 10 came through on April 18th . I was using the same set of roads for the last 7 of these tunes so that it was consistent and I could feel the difference in acceleration . I was running out of road much quicker

The next step was to arrange a dyno day to do the Vanos tuning which you wouldn`t think would be a problem but Josh is in Hawaii which is currently 11 hours behind the UK . I spoke to my Dyno man Graham and he said he couldn`t start before 8am or go beyond 6pm as there are some houses not far away . This meant that we arranged to start at 8 am on Tuesday 14th May which was 9pm Monday 13th May in Hawaii .
Unfortunately I was held up on the way to Graham which is about an 1hr 15 mins away from me due to slow lorries down winding lanes and a BMW that looked like it had done a 360 on the A55 and was smashed into some trees . Police were there but no ambulance so hopefully they were ok . I turned up at 7.30 and by the time Graham had set everything up it was nearer 9am but Josh took it all in his stride .
We were supposed to be doing a 3 hour session but we ended up doing 12 tunes on the dyno sending logs and graphs to Josh and him sending the tune back .
We finally finished at 12.45 UK time which was 1.45 am in Hawaii !!
Josh said that the high end was almost dialed in already from the road logging we had done but the Exhaust Vanos tuning is where he got most gains in the mid range .

Josh has got as much as you are going to get out of this N52 engine without changing the inlet manifold or possibly cams. Vanos is Maxed out .

Points to note though are that this is an auto box so will probably get more from a manual and you may see higher numbers elsewhere but all Dyno`s are not equal . From a driving point of view its more than enough power for me and it is in the right place .

I`ve got to say that I would definitely agree with all the excellent comments I have seen praising Josh@Severn Tuning he was very informative about what was happening throughout and nothing seemed too much bother . His forum name is pokeybritches,

Graham the Dyno man works from Holywell in Flintshire if anyone wants to use his Hub Dyno for a fee of course . He doesn`t tune BMW ECU`s but does work with Syvecs if you wanted a stand alone ECU to go racing .

All dyno runs were done in fourth gear only and are recorded as wheel horse power not brake horse power .

On the graphs please take into account T10 has a high humidity level so probably best to take T11 and compare it to T22 . Unfortunately I didn`t notice at the time otherwise I would have asked for a T11 and T22 graph comparison . T15 unfortunately doesn`t show on the table at the bottom .

Sorry PDF `s don`t attach so I screen printed them into paint and they are not very clear .

Tune 11 was WHP 199.16 @ 5870 RPM and Wheel Torque 211.66 @ 4493 RPM which is low as this is how Josh works out the correct tune for Vanos
Tune 22 Final tune was WHP 235.05@ 5880 RPM and Wheel Torque 228.97 lb/ft @ 3734 RPM

T11 to 15.jpg (103.47 KiB) Viewed 329 times

T16 to 18.jpg (96.46 KiB) Viewed 329 times

T19 to 21.jpg (97.5 KiB) Viewed 329 times

[1536Z4]

Some photos taken today

[Joycey]

Great read this, My coupe has been going through development with BDS they've been taking the N52 engines over 300bhp NA, really impressive work. I've had the first bits done with mine she's now at 270 and I've just spent the weekend enjoying her at the Ring.

For context, they have their own intake design they also have their own valvetronic arms with extra lift. This with a custom 6 branch and race cat in the mid section they're all achieving 300+ on the dyno. The track coupe they have is 317.

The next step of development is really exciting, I cant say publicly but the numbers on the Dyno don't lie that's for sure. The N52 engine will really begin to become more popular the more known this type of work becomes.

[AdyBish]

Some photos taken today

Fabulous looking coupe Sir. I’ve never been a rear wing fan until now. Epic.

[1536Z4]

For context, they have their own intake design they also have their own valvetronic arms with extra lift.

Thanks Lee,

Bet the ring was fun

I have been looking at the BDS videos recently including the ITG filter set up . All looking good but I know that there seems to be a bit of bad vibes about their testing on MILVs see here https://www.e90post.com/forums/showthread.php?t=2047661 and the thought that they had bought a fake set from the UK not direct from the US . What we really need is for someone to design an intake manifold for the N52 to get over the loss of power around 6400 RPM so I hope that is something they are going to look into. Great to see the N52 getting some love .

[1536Z4]

Fabulous looking coupe Sir. I’ve never been a rear wing fan until now. Epic.

Thank you Joycey had his rear wing done first and its definitely a marmite subject

[Meds]

Some photos taken today

Get some black on those tyres sonny.

[Joycey]

For context, they have their own intake design they also have their own valvetronic arms with extra lift.

Thanks Lee,

Bet the ring was fun

I have been looking at the BDS videos recently including the ITG filter set up . All looking good but I know that there seems to be a bit of bad vibes about their testing on MILVs see here https://www.e90post.com/forums/showthread.php?t=2047661 and the thought that they had bought a fake set from the UK not direct from the US . What we really need is for someone to design an intake manifold for the N52 to get over the loss of power around 6400 RPM so I hope that is something they are going to look into. Great to see the N52 getting some love .

Think you’re mixing up MILVs with valvetronic arms. The MILV’s don’t work which partly why you can’t buy them anymore. BDS make their own arms that give the valves longer opening times etc. All the work and dyno print outs are on his Instagram.

[1536Z4]

The MILV’s don’t work which partly why you can’t buy them anymore.

Sorry Lee but it is only BDS that say the MILV`s don`t work .They didn`t buy the original MILV`s from the US they bought knock off MILV`s . Did you read through the link I posted ?
I`m sure their arms work fine but to say that MILV`s don`t work is just wrong without using the original US MILV`s . There has been loads of testing in the US and they have proved they work . I wish BDS all the best with their performance gains but they shouldn`t try to disprove MILV`s buy using items not bought from Bimmermilvs direct . I see that all the figures are provided by BDS but that is the issue they are provided by BDS but I havn`t seen figures provided by anyone else unlike MILVs that have had figures provided by various people in the US . I don`t want to get into a slanging match about it but figures provided by a person/company that is producing the product and using their Dyno need to be taken with a pinch of salt until more people have tried their product and done their own testing . I`m all for getting the most out of the N52 as you can probably tell and if their product ends up being proven over a broader range or users and tuners and they can prove that the original US MILV`s don`t work then I will happily jump ship and hand over the wonga for them Are you going to Zedfest it would be great to meet up and discuss

[1536Z4]

Get some black on those tyres sonny.

Round here I would have to be blacking them up every time I went out . We are surrounded by farms dropping cow manure and mud all over the roads . I suppose I could have done for the photos if I had any

[Joycey]

The MILV’s don’t work which partly why you can’t buy them anymore.

Sorry Lee but it is only BDS that say the MILV`s don`t work .They didn`t buy the original MILV`s from the US they bought knock off MILV`s . Did you read through the link I posted ?
I`m sure their arms work fine but to say that MILV`s don`t work is just wrong without using the original US MILV`s . There has been loads of testing in the US and they have proved they work . I wish BDS all the best with their performance gains but they shouldn`t try to disprove MILV`s buy using items not bought from Bimmermilvs direct . I see that all the figures are provided by BDS but that is the issue they are provided by BDS but I havn`t seen figures provided by anyone else unlike MILVs that have had figures provided by various people in the US . I don`t want to get into a slanging match about it but figures provided by a person/company that is producing the product and using their Dyno need to be taken with a pinch of salt until more people have tried their product and done their own testing . I`m all for getting the most out of the N52 as you can probably tell and if their product ends up being proven over a broader range or users and tuners and they can prove that the original US MILV`s don`t work then I will happily jump ship and hand over the wonga for them Are you going to Zedfest it would be great to meet up and discuss

I completely agree. For me though it’s proof in the pudding I’m going on what I’ve seen with my own eyes, ive been with my coupe coming up 10 years and very few company’s dare to venture down this N52 road, I don’t know the back story behind the who made what etc and couldn’t careless my kit was bought from the states years ago so only going by my experience and another member who also tracks with me, my results so far are backed up by two different dynos and both being well known so no issues there.

All this work is still early stages and he’s keeping quite a bit under wraps at the moment. My biggest concern at the moment is how this effect the life of the N52, all this extra power is it really sustainable. Mines on 160k with 40+ track days.

Be good to have a chat one day. Don’t really do shows anymore. I’m either building something or playing on tracks somewhere. If your bored you’ll find me in a barn surrounded by zeds.

[1536Z4]

my kit was bought from the states years ago so only going by my experience and another member who also tracks with me, my results so far are backed up by two different dynos and both being well known so no issues there.

That`s good to know . I will keep an eye on how it progresses .

Be good to have a chat one day. Don’t really do shows anymore. I’m either building something or playing on tracks somewhere. If your bored you’ll find me in a barn surrounded by zeds.

[Meds]

My biggest concern at the moment is how this effect the life of the N52, all this extra power is it really sustainable. Mines on 160k with 40+ track days.

Yes, a concern.
Didn't their development Z4 throw its chain recently?