Z4 35is mods

[TurboSnail]

The plan to modify my 2011 Z4 35is (DCT) has now officially gone from the idea phase to implementation. The general plan is to install a larger FMIC, an induction kit and an map in order to get the power to 400ish Right now the car is stock and it has done 45K km.

I’m planning to use the MHD Tuning for flashing the ECU with either their Stage 1+ or the Stage 2+ map. As I’m not updating the downpipes, I’m unsure if the 2+ is a viable way to go. Any experience/advice?

A nice big box just arrived from Wagner Tuning in Germany Tuesday with my new intercooler. Looking good and it’s suppose to be an easy “bolt-on” fit. (Fingers crossed!) My induction kit arrived yesterday and I spent a couple of hours installing both. Pretty straight forward - especially with the car on a lift.

I have installed the flasher and the monitor function, and done a backup of the cars sw. Also did a few runs to see what kind of boost/power the car is generating with the new induction kit and intercooler. Pretty good logging functionality and a good baseline to compare with - once I flash the new map.

I also got a dyno time booked to get some documentation of the results of the mods. Unfortunately the did not have time before another two weeks (summer vacation time in Denmark).

Updates will follow...

 

[sunnydays]

Subbed

Will you be installing a new charge pipe given that the stock plastic pos will probably blow off at stage 2+.

Additionally when were your coils and spark plugs last done, pretty common to need to change coils / sparks post remap due to misfires.

Stage 1+ is blistering fast compared to stock. Imo wait until you have down pipes before you go stage 2+.

What octane fuel will you be running?

Do the intakes actually make any difference apart from the induction noise. If I remember correctly the 35is has a larger intake box with more air flow than other n54 cars. A few 335i owners were upgrading to the 35is box rather than dci.

And lastly any suspension mods? What tyres are you running?

 

[enzed4]

This is exactly what I've been looking into, but prices have been putting me off.
I'd like to go back to the stock box (35i has the same larger sized intake box as the 35is as far as I'm aware) with an aftermarket filter, but I suspect it will end up costing as much (or more) as the AFE intake you have bought. 35i's wrecking are rear as rocking horse sh*t around here. I know about the 'pointlessness' of putting exposed intake filters in a hot engine bay, but the AFE setup you have seems to be the best compromise I've seen, and at least tries to channel cooler air directly onto the intakes, as well as providing some shielding from the hot engine with the open-box design.
Also looking at the VRSF FMIC (the 5" stepped), and the MHD flasher, so I'll be following at this thread with interest
Best of luck.

 

[mcbutler]

Glad to see your doing the intercooler, essential.
I read a post a while back from a guy in US who tunes N54 and pretty much nothing else for a living.
He said that simply Knocking the cat material out of the downpipes fine up to 450 BHP, then you need modified pipes!

 

[sunnydays]

This is exactly what I've been looking into, but prices have been putting me off.
I'd like to go back to the stock box (35i has the same larger sized intake box as the 35is as far as I'm aware) with an aftermarket filter, but I suspect it will end up costing as much (or more) as the AFE intake you have bought. 35i's wrecking are rear as rocking horse sh*t around here. I know about the 'pointlessness' of putting exposed intake filters in a hot engine bay, but the AFE setup you have seems to be the best compromise I've seen, and at least tries to channel cooler air directly onto the intakes, as well as providing some shielding from the hot engine with the open-box design.
Also looking at the VRSF FMIC (the 5" stepped), and the MHD flasher, so I'll be following at this thread with interest
Best of luck.

Pretty sure the AFE intakes produce less BHP than the stock intake, I read a thread over on the E90 forums with logs / comparisons before and after

 

[enzed4]

This is exactly what I've been looking into, but prices have been putting me off.
I'd like to go back to the stock box (35i has the same larger sized intake box as the 35is as far as I'm aware) with an aftermarket filter, but I suspect it will end up costing as much (or more) as the AFE intake you have bought. 35i's wrecking are rear as rocking horse sh*t around here. I know about the 'pointlessness' of putting exposed intake filters in a hot engine bay, but the AFE setup you have seems to be the best compromise I've seen, and at least tries to channel cooler air directly onto the intakes, as well as providing some shielding from the hot engine with the open-box design.
Also looking at the VRSF FMIC (the 5" stepped), and the MHD flasher, so I'll be following at this thread with interest
Best of luck.

Pretty sure the AFE intakes produce less BHP than the stock intake, I read a thread over on the E90 forums with logs / comparisons before and after

Oh I don't doubt it, my problem is that it's highly unlikely I'll find a stock intake, so will have to find the next best thing. I'm open to any suggestions, but that AFE looks to be the best non-stock I've seen so far.

 

[sunnydays]

This is exactly what I've been looking into, but prices have been putting me off.
I'd like to go back to the stock box (35i has the same larger sized intake box as the 35is as far as I'm aware) with an aftermarket filter, but I suspect it will end up costing as much (or more) as the AFE intake you have bought. 35i's wrecking are rear as rocking horse sh*t around here. I know about the 'pointlessness' of putting exposed intake filters in a hot engine bay, but the AFE setup you have seems to be the best compromise I've seen, and at least tries to channel cooler air directly onto the intakes, as well as providing some shielding from the hot engine with the open-box design.
Also looking at the VRSF FMIC (the 5" stepped), and the MHD flasher, so I'll be following at this thread with interest
Best of luck.

Pretty sure the AFE intakes produce less BHP than the stock intake, I read a thread over on the E90 forums with logs / comparisons before and after

Oh I don't doubt it, my problem is that it's highly unlikely I'll find a stock intake, so will have to find the next best thing. I'm open to any suggestions, but that AFE looks to be the best non-stock I've seen so far.

Why not just put some BMS DCI's on, and leave the stock air snorkel on so that cool air is hitting the intakes directly?

 

[Miyli]

Air scoops are a great way to add air.
Easy to do yourself when not ready e89.

 

[Chris1712]

Very interested to see exactly how easy the FMIC is to swap over, something I'd like to do but I only have my driveway / simple tools.

Did you consider any other FMICs? Lots of people going for chinese units on bimmerpost.

 

[enzed4]

Pretty sure the AFE intakes produce less BHP than the stock intake, I read a thread over on the E90 forums with logs / comparisons before and after

Oh I don't doubt it, my problem is that it's highly unlikely I'll find a stock intake, so will have to find the next best thing. I'm open to any suggestions, but that AFE looks to be the best non-stock I've seen so far.

Why not just put some BMS DCI's on, and leave the stock air snorkel on so that cool air is hitting the intakes directly?

This is exactly what I have, but I've not seen those JB4 scoops before.

 

[R.E92]

I don't think you need to bother upgrading the chargepipe. I've had the car running at 18PSI for 6 years now with the stock pipe. Also the DCI are a complete waste of money.

The key things to sort on the 35i/s for more power are:
Custom MHD map
Upgraded intercooler
Catless downpipes

With the custom map you want to find a tuner that can incorporate the new throttle correction tables into the map, most of the popular N54 tuners like Wedge or Twisted Tuning should be able to do that for you. They transform the way the car drives and solve the dead pedal feeling at low speeds with the DCT.

The catless downpipes greatly reduce the spool time of the turbos and free up a good amount of power.

 

[enzed4]

I don't think you need to bother upgrading the chargepipe. I've had the car running at 18PSI for 6 years now with the stock pipe. Also the DCI are a complete waste of money.

The key things to sort on the 35i/s for more power are:
Custom MHD map
Upgraded intercooler
Catless downpipes

With the custom map you want to find a tuner that can incorporate the new throttle correction tables into the map, most of the popular N54 tuners like Wedge or Twisted Tuning should be able to do that for you. They transform the way the car drives and solve the dead pedal feeling at low speeds with the DCT.

The catless downpipes greatly reduce the spool time of the turbos and free up a good amount of power.

Very good information - thanks. I was about to order a chargepipe, as I keep reading (always anecdotal) stories of the chargepipe 'blowing' under the pressure. I'm not intending on boosting that much anyway.
Definitely will go with the FMIC, but the catless downpipes seem like a lot of effort to fit, I'm not sure I'm up to it.
Curious about the custom mapping you mention. Is there any reason not to go with the MHD 'stock' tunes or whatever they're called? e.g. Stage 1 or 1+, 2 etc.

 

[R.E92]

I don't think you need to bother upgrading the chargepipe. I've had the car running at 18PSI for 6 years now with the stock pipe. Also the DCI are a complete waste of money.

The key things to sort on the 35i/s for more power are:
Custom MHD map
Upgraded intercooler
Catless downpipes

With the custom map you want to find a tuner that can incorporate the new throttle correction tables into the map, most of the popular N54 tuners like Wedge or Twisted Tuning should be able to do that for you. They transform the way the car drives and solve the dead pedal feeling at low speeds with the DCT.

The catless downpipes greatly reduce the spool time of the turbos and free up a good amount of power.

Very good information - thanks. I was about to order a chargepipe, as I keep reading (always anecdotal) stories of the chargepipe 'blowing' under the pressure. I'm not intending on boosting that much anyway.
Definitely will go with the FMIC, but the catless downpipes seem like a lot of effort to fit, I'm not sure I'm up to it.
Curious about the custom mapping you mention. Is there any reason not to go with the MHD 'stock' tunes or whatever they're called? e.g. Stage 1 or 1+, 2 etc.

The built-in maps are very good, certainly far superior to anything else available at a garage but they do leave power on the table and also lack cutting edge developments.
The big development recently has been the table discovery related to the input filtering on the accelerator pedal relating to throttle movements. The BMW 1M had these tables all set to 0 which meant the car felt much more lively to drive than other N54 engined cars. Now with these tables exposed people can have 1M style throttle response on the Z4. I've been tweaking my own map with these new tables and it hugely improves responsiveness.

It might take another few months for MHD to add these throttle changes to the built-in maps but a custom tuner can do it straight away.

 

[enzed4]

The plan to modify my 2011 Z4 35is (DCT) has now officially gone from the idea phase to implementation. The general plan is to install a larger FMIC, an induction kit and an map in order to get the power to 400ish Right now the car is stock and it has done 45K km.

I’m planning to use the MHD Tuning for flashing the ECU with either their Stage 1+ or the Stage 2+ map. As I’m not updating the downpipes, I’m unsure if the 2+ is a viable way to go. Any experience/advice?

A nice big box just arrived from Wagner Tuning in Germany Tuesday with my new intercooler. Looking good and it’s suppose to be an easy “bolt-on” fit. (Fingers crossed!) My induction kit arrived yesterday and I spent a couple of hours installing both. Pretty straight forward - especially with the car on a lift.

I have installed the flasher and the monitor function, and done a backup of the cars sw. Also did a few runs to see what kind of boost/power the car is generating with the new induction kit and intercooler. Pretty good logging functionality and a good baseline to compare with - once I flash the new map.

I also got a dyno time booked to get some documentation of the results of the mods. Unfortunately the did not have time before another two weeks (summer vacation time in Denmark).

Updates will follow...

How's this going OP? Any updates? We've kind of hijacked your thread with related discussion while waiting for your results.

 

[Miyli]

MHD Stage 2 or stage 2+ good option, i don't need MHD 20000 miles without problems. You should also change downpipes and update fmci.

 

[TurboSnail]

I have been driving the car with the new setup for almost a week now and all is good. The performance has definitely improved and funnily enough the fuel (in)efficiency doesn’t seem to suffer - if anything it has improved. For fuel, I use Shell V-power 100 octane. Haven’t had much time to fool around with options in MHD.

Reading the comments, I not sure if an upgraded charge pipe and blow-off valve is a necessity (but none of this really is). Going to a proper blow-off is supposed to make a notable difference compared to the stock diverter valves. Do you have any recommendations to which solution to go for?

Upgraded downpipes would need to be equipped with high-flow cats, otherwise I don’t stand a chance in a Danish MOT. These are kind of pricey :roll: But they are on the wish list.

Next week I will see what the Dyno figures say I will post the results as soon as I have them.

 

[TurboSnail]

Very interested to see exactly how easy the FMIC is to swap over, something I'd like to do but I only have my driveway / simple tools.

Did you consider any other FMICs? Lots of people going for chinese units on bimmerpost.

I got the Wagner intercooler because it’s made for the car. They also make even bigger ones for the E89. You can use a generic one, but I’m sure the installation will be more of a pain.

The install of the intercooler was so straight forward that I didn’t bother to take any pictures. Just remove the covering to get access (quite a few bolts). Then un-clip the two c-clips and remove the two bolts holding the intercooler in place an take it out. Installing the Wagner intercooler is just the reverse process with some wriggling to everything to fit nicely. The instructions can be found on Wagner Tuning’s website and a few YouTube videos.

It can be done in the driveway, but I spent the coin and rented garage space with a lift for one hour - makes everything a lot easier

 

[TurboSnail]

Pretty sure the AFE intakes produce less BHP than the stock intake, I read a thread over on the E90 forums with logs / comparisons before and after

Oh I don't doubt it, my problem is that it's highly unlikely I'll find a stock intake, so will have to find the next best thing. I'm open to any suggestions, but that AFE looks to be the best non-stock I've seen so far.

Why not just put some BMS DCI's on, and leave the stock air snorkel on so that cool air is hitting the intakes directly?

It would be cool to an actual test of the aFe filters vs the stock one on a dyno. I don’t buy aFe’s power gain claims, but I also don’t see that they would harm performance. Seriously, the best reason for installing this is most likely for the look and the sound And that is a matter of personal preference. I hated the aFe filter that came with my E85 and I always ran the stock filter on that car :wink:

 

[sunnydays]

I have been driving the car with the new setup for almost a week now and all is good. The performance has definitely improved and funnily enough the fuel (in)efficiency doesn’t seem to suffer - if anything it has improved. For fuel, I use Shell V-power 100 octane. Haven’t had much time to fool around with options in MHD.

Reading the comments, I not sure if an upgraded charge pipe and blow-off valve is a necessity (but none of this really is). Going to a proper blow-off is supposed to make a notable difference compared to the stock diverter valves. Do you have any recommendations to which solution to go for?

Upgraded downpipes would need to be equipped with high-flow cats, otherwise I don’t stand a chance in a Danish MOT. These are kind of pricey :roll: But they are on the wish list.

Next week I will see what the Dyno figures say I will post the results as soon as I have them.

Looking forward to the Dyno! What stage MHD did you end up running, and V7 or V8 maps?

It would be cool to an actual test of the aFe filters vs the stock one on a dyno. I don’t buy aFe’s power gain claims, but I also don’t see that they would harm performance. Seriously, the best reason for installing this is most likely for the look and the sound And that is a matter of personal preference. I hated the aFe filter that came with my E85 and I always ran the stock filter on that car :wink:

Yes the sound is great! They look great too haha. Same reason I recently fitted DCI's to my car

 

[enzed4]

Thanks for the updates on your progress, turbosnail. Interesting about needing a better chargepipe if you go with catless downpipes, maybe I need to add one back into the shopping list.
Having seen the higher temps using DCI's (I think on ZPost? Easy to google), personally I would still like to go back to a stock airbox with an uprated filter.