Searching for 400hp in a 335i N55

[RacerX5]

Hello all;

I just acquired my first turbocharged BMW, a 2011 335i M-Sport Coupe with an N55. I'd like to bump the power to about 400 crank HP at this point. There are SO many variations of available aftermarket parts for these cars, (although not as much as for the N54 cars,) it's a little daunting to pick the right parts to buy. The only mod to the car currently is a metal charge pipe.

Aside from the HP goal, I'd like to keep the car as stock sounding (quiet,) as possible, and have it as bullet-proof reliable as possible. But I'm somewhat flexible on this point. It will be autocrossed and taken to track days on a somewhat regular basis, but still street driven. As far as fuel, it will need to be tuned for 91 octane.

If anyone can suggest an overall plan for this car, it would be greatly appreciated.

[wgknestrick]

Hello all;

I just acquired my first turbocharged BMW, a 2011 335i M-Sport Coupe with an N55. I'd like to bump the power to about 400 crank HP at this point. There are SO many variations of available aftermarket parts for these cars, (although not as much as for the N54 cars,) it's a little daunting to pick the right parts to buy. The only mod to the car currently is a metal charge pipe.

Aside from the HP goal, I'd like to keep the car as stock sounding (quiet,) as possible, and have it as bullet-proof reliable as possible. But I'm somewhat flexible on this point. It will be autocrossed and taken to track days on a somewhat regular basis, but still street driven. As far as fuel, it will need to be tuned for 91 octane.

If anyone can suggest an overall plan for this car, it would be greatly appreciated.

I had a 2011 335 where I had the same aspirations as you. My car was a 6AT-AWD though and I did not have a good experience as it would throw tranny codes about once a month. I was also throwing CELs, but this was pre BEF-MHD / (only JB4) days. I ultimately returned to stock and sold it due to being frustrated with codes.

Mods
BEF-MHD
Downpipe - Exhaust
VRSF intercooler
Al intercooler piping
Intake

This should get you there or close on 91oct. Pure turbo will definitely get you there, but that probably isn't worth it IMO unless you have high miles on OEM.

[awp235]

With a custom tune and meth, your goal should be nearly attainable. You'll need to be full bolt on- turbo inlet, downpipe, intercooler (larger the better, such as a vrsf race, since you plan on tracking). Meth would bring you to 400whp if you're willing to run e30-e50. I know you said 91 pump, but if you're looking for an honest 400 at the wheels, it likely won't happen without meth and a very good dyno tune, with a tuner that knows what they're doing.

[Hova]

I had a 2011 335 where I had the same aspirations as you. My car was a 6AT-AWD though and I did not have a good experience as it would throw tranny codes about once a month. I was also throwing CELs, but this was pre BEF-MHD / (only JB4) days. I ultimately returned to stock and sold it due to being frustrated with codes.

Mods
BEF-MHD
Downpipe - Exhaust
VRSF intercooler
Al intercooler piping
Intake

This should get you there or close on 91oct. Pure turbo will definitely get you there, but that probably isn't worth it IMO unless you have high miles on OEM.

Likely needed a transmission fluid change and/or needed to load XHP for your transmission. Changes the way the car drives completely.

[Hova]

Hello all;

I just acquired my first turbocharged BMW, a 2011 335i M-Sport Coupe with an N55. I'd like to bump the power to about 400 crank HP at this point. There are SO many variations of available aftermarket parts for these cars, (although not as much as for the N54 cars,) it's a little daunting to pick the right parts to buy. The only mod to the car currently is a metal charge pipe.

Aside from the HP goal, I'd like to keep the car as stock sounding (quiet,) as possible, and have it as bullet-proof reliable as possible. But I'm somewhat flexible on this point. It will be autocrossed and taken to track days on a somewhat regular basis, but still street driven. As far as fuel, it will need to be tuned for 91 octane.

If anyone can suggest an overall plan for this car, it would be greatly appreciated.

With a custom tune and meth, your goal should be nearly attainable. You'll need to be full bolt on- turbo inlet, downpipe, intercooler (larger the better, such as a vrsf race, since you plan on tracking). Meth would bring you to 400whp if you're willing to run e30-e50. I know you said 91 pump, but if you're looking for an honest 400 at the wheels, it likely won't happen without meth and a very good dyno tune, with a tuner that knows what they're doing.

N54 and N55 have similar potentials and similar quirks. 400 crank HP out of either motor is laughable and can be done pretty easily.

You only need MHD, an android phone or tablet, an INPA cable or the WiFi MHD dongle (HIGHLY suggest this), cat-less downpipes, and a new intercooler.


WiFi dongle:
https://burgertuning.com/products/mh...-flash-adapter


Tune and charts:
https://mhdtuning.com/mhd-flasher-f-series-n55/


That's it. The off the shelf tunes work well on 91, the colder the intake air is the better, the bigger the intercooler the better in this case. I'm running the VRSF 7.5" stepped.

Stay away from meth, complete waste of money and it's only a crappy band aid for the problem of IAT and fueling.

Installing an aftermarket downpipe will make the exhaust slightly deeper.

Don't bother with JB4, waste of money considering what MHD can do. When loading MHD seriously plug in a 10-15amp battery charger.

If you're an automatic, I strongly recommend you checkout the XHP tunes. They completely change the way the car shifts and responds.

https://www.youtube.com/watch?v=dXbC6sC_6cM

Close to DCT shift speeds on the auto. Lots of 10 second automatic 335i's out there, not many manuals.

[wgknestrick]

Likely needed a transmission fluid change and/or needed to load XHP for your transmission. Changes the way the car drives completely.

I was pre - MHD and transmission flashes.

[RacerX5]

N54 and N55 have similar potentials and similar quirks. 400 crank HP out of either motor is laughable and can be done pretty easily.

You only need MHD, an android phone or tablet, an INPA cable or the WiFi MHD dongle (HIGHLY suggest this), cat-less downpipes, and a new intercooler.


WiFi dongle:
https://burgertuning.com/products/mh...-flash-adapter


Tune and charts:
https://mhdtuning.com/mhd-flasher-f-series-n55/


That's it. The off the shelf tunes work well on 91, the colder the intake air is the better, the bigger the intercooler the better in this case. I'm running the VRSF 7.5" stepped.

Stay away from meth, complete waste of money and it's only a crappy band aid for the problem of IAT and fueling.

Installing an aftermarket downpipe will make the exhaust slightly deeper.

Don't bother with JB4, waste of money considering what MHD can do. When loading MHD seriously plug in a 10-15amp battery charger.

If you're an automatic, I strongly recommend you checkout the XHP tunes. They completely change the way the car shifts and responds.

https://www.youtube.com/watch?v=dXbC6sC_6cM

Close to DCT shift speeds on the auto. Lots of 10 second automatic 335i's out there, not many manuals.

Thanks for all the info. I have a couple of questions.

Assuming I go to catless downpipes, how does the MHD deal the lack of O2 sensors?

So you recommend the biggest possible intercooler even with the modest 35% HP gain I'm looking for? No downside to this other than cost and a little trimming?

[Hova]

Thanks for all the info. I have a couple of questions.

Assuming I go to catless downpipes, how does the MHD deal the lack of O2 sensors?

So you recommend the biggest possible intercooler even with the modest 35% HP gain I'm looking for? No downside to this other than cost and a little trimming?

You will be keeping all of the O2 sensors intack, and I highly recommend you change the two upper O2 sensors, the rears will be pretty much useless, MHD will take care of that.

You can go with the biggest intercooler, but a regular 7" will work great too. The only reason I mentioned it was because you plan on tracking the car. The issue here is keeping the intake temps as low as possible.

https://www.e90post.com/forums/showthread.php?t=1054107

Here is the difference between the intercooler sizes, the race model is a stepped one, and looks far far better in the bumper.

https://www.n54tech.com/forums/showthread.php?t=48456

Here you go:

https://www.ebay.com/itm/7-5-Stepped...EAAOSwEtRc85WA

[awp235]

I'd love to see a dyno of someone on an MHD catless 91 tune hitting 400 wheel, from an n54 or n55. Unless the tunes have gotten substantially more aggressive in the last year, realistically you're only going to pull 380-385 at the wheels without corn juice mixed in. even on 93, it's not 400 wheel.

If you're considering getting an XHP tune, please look up Rod Sutphin on facebook. He runs Sutphin tuning and he takes XHP tunes and rebuilds them from teh ground up to an amazingly quick, powerful shift map that is supremely driveable and faster than XHP maps when driving aggressively. He's been tuning the 335d and x5d trans's for years now, and hes simply perfected the maps. Now he's moved on to conquering the gas trans offerings.

[Hova]

I'd love to see a dyno of someone on an MHD catless 91 tune hitting 400 wheel, from an n54 or n55. Unless the tunes have gotten substantially more aggressive in the last year, realistically you're only going to pull 380-385 at the wheels without corn juice mixed in. even on 93, it's not 400 wheel.

If you're considering getting an XHP tune, please look up Rod Sutphin on facebook. He runs Sutphin tuning and he takes XHP tunes and rebuilds them from the ground up to an amazingly quick, powerful shift map that is supremely driveable and faster than XHP maps when driving aggressively. He's been tuning the 335d and x5d trans's for years now, and hes simply perfected the maps. Now he's moved on to conquering the gas trans offerings.

400 crank hp, as he said above. 400whp is pretty easy to hit too these days though with corn. You don't even need port injection, a helicoil overdrive pump can give you enough fuel on the high side for the power.


Rod Sutphin is great, I do worry about the trans tunes at times though with unserviced transmissions. At least all of the seals on the valve body should be done to keep up with the pressure increase, fairly straight forward job. The 335d tunes I've seen of his are amazing, and can hold SERIOUS torque.