To be honest I don't think it is really worth investing into this engine. If you want more power buy something like a 328/330 or something. I have both a 328 and a 316, and the 328 is way more fun to drive.

 

Yeah I had the same concern, thanks.

 

Is there a big tax penalty going above 2 litres in Sweden? I can't imagine otherwise why you'd start with a little 4 cylinder engine rather than the big 6 if you want performance. If it's because you're still young and insurance is a problem then they're hardly likely to insure you cheaply after you've modified it.

 

Yes that is true. At my age it would cost approximately 1200 usd per month to have a bigger engine...

 

Hi Melvin,

A fellow 4-cylinder owner here. I have looked into tuning options for the N42 engine. It seems that tuning options are slim, unless you want to rebuild with different engine parts, and it is said that such changes may be better for racing than daily use.

A guy on a Danish FB E46 page claimed that the N42 was 'easy' to tune with parts like pistons and cams from a Saab, I believe. If I can find his post I will share it.

I found these two links:

All you need to know about tuning the N42B18 N42B20 engine from BMW

We review N42 tuning and highlight the ultimate modifications for your car. BMW N42 are good project engines and with the right performance enhancements like ECU maps, turbo improvements and camshafts you will really maximize your driving opportunities.

www.torquecars.com

Modding upgrading and tuning the BMW N42 engine!

We review and look into N42 tuning and report on the greatest modifications. BMW N42 are good project engines and with the right motorsport parts like remaps, turbo kits and camshafts you will substantially maximise your cars bhp and torque.

www.cartuningtips.com

For my own car I have considered getting an ECU tuning. A Danish company advertises decent power gains using this method. But essential repairs always eat up the tuning budget.

Schmiedmann has a large selection of various tuning parts, maybe you can find what you need there:

BMW E46 Sedan 316i N42 - Tuning og optimering - Schmiedmann - Nye dele

BMW E46 Sedan 316i N42 - Tuning og optimering - Schmiedmann - Nye dele

www.schmiedmann.dk

Last note, this forum is mostly populated by US users, none of whom own the 4-cylinder models. You may have better luck getting N42 specific advice on a UK/EU based forum.

Let's know if you find a way to get some more power to your wheels. DIYs with photos are much appreciated.

 

Hi Melvin,

A fellow 4-cylinder owner here. I have looked into tuning options for the N42 engine. It seems that tuning options are slim, unless you want to rebuild with different engine parts, and it is said that such changes may be better for racing than daily use.

A guy on a Danish FB E46 page claimed that the N42 was 'easy' to tune with parts like pistons and cams from a Saab, I believe. If I can find his post I will share it.

I found these two links:

All you need to know about tuning the N42B18 N42B20 engine from BMW

We review N42 tuning and highlight the ultimate modifications for your car. BMW N42 are good project engines and with the right performance enhancements like ECU maps, turbo improvements and camshafts you will really maximize your driving opportunities.

www.torquecars.com

Modding upgrading and tuning the BMW N42 engine!

We review and look into N42 tuning and report on the greatest modifications. BMW N42 are good project engines and with the right motorsport parts like remaps, turbo kits and camshafts you will substantially maximise your cars bhp and torque.

www.cartuningtips.com

For my own car I have considered getting an ECU tuning. A Danish company advertises decent power gains using this method. But essential repairs always eat up the tuning budget.

Schmiedmann has a large selection of various tuning parts, maybe you can find what you need there:

BMW E46 Sedan 316i N42 - Tuning og optimering - Schmiedmann - Nye dele

BMW E46 Sedan 316i N42 - Tuning og optimering - Schmiedmann - Nye dele

www.schmiedmann.dk

Last note, this forum is mostly populated by US users, none of whom own the 4-cylinder models. You may have better luck getting N42 specific advice on a UK/EU based forum.

Let's know if you find a way to get some more power to your wheels. DIYs with photos are much appreciated.

Sorry to say, but the first two links are totally useless collection of internet tuning bullshit bingo.

No one, as of my intensive research, did tune the N42/46 naturally aspirated. As far as i know, i´m the first one doing so and from what i can tell you right now, it won´t be cheap. I expect 185-190PS (do your own conversion into your familiar unit), driveability is expected to be stock-like.

I´m currently gathering all the parts needed, should be done by the end of the month. Afterwards the components get shipped to my engine builder to match them. When all is set up properly incl. DME optimization, i´ll go to the dyno.

Why don´t i simply put in a M54? Because i already have 330i convertible and 330i touring and, most important, i can.

 

Hey! Thanks a lot! This was the kind of answer I was hoping to get. Not just like "yeah buy a 6 cylinder" I will certainly look at those links and I already planned to rebuild it. Tuned 4 cylinders kan sound pretty mean like most rally cars. Thanks again and good luck with yours!

 

That turbo kit looks interesting. Especially considering the limited options for the N42, it's nice to just see something, anything.



Yeah, us 4-star generals gotta stick together. The other answer I've seen too many times, so I wanted encourage some mild dissent. It may be true that 6 is better, but if 4 is what you have to work with until your insurance premiums improve with age, make the best of it! I for one will be very interested in learning where you go with this.

I recently found out that the insurance / taxes difference is not that great for me, so I will probably save up for a 328 or 330, or consider an engine swap down the line.

 

But what is the difference you pay per month extra for a 6 cyl compared to a 4 cyl? Where I live (the Netherlands) I think on monthly base I pay like 20 euro's extra. When I first bought my 4 cyl I was also looking into upgrading engine parts for gaining power, but in my opinion it just isn't worth it. Also on general the 6 cylinder engines are way more reliable compared to the 4 cylinder N42 engines. "just buy a 6 cylinder" is not just the easy answer, I think it is the answer most people will figure out over time when they figure out there is not much which can be done with these engines.

But if you really want to get some power you might want to look into this: Kit turbo BMW 4 cyl Stage 1

I would contact them and ask more information about the kit like if it is bolt on or if you need to customize more stuff in order to make it work. Also I don't know if you have a manual or automatic transmission? I know some people have issues with the automatic transmission when tuning these engines.

 

But what is the difference you pay per month extra for a 6 cyl compared to a 4 cyl? Where I live (the Netherlands) I think on monthly base I pay like 20 euro's extra. When I first bought my 4 cyl I was also looking into upgrading engine parts for gaining power, but in my opinion it just isn't worth it. Also on general the 6 cylinder engines are way more reliable compared to the 4 cylinder N42 engines. "just buy a 6 cylinder" is not just the easy answer, I think it is the answer most people will figure out over time when they figure out there is not much which can be done with these engines.

But if you really want to get some power you might want to look into this: Kit turbo BMW 4 cyl Stage 1

I would contact them and ask more information about the kit like if it is bolt on or if you need to customize more stuff in order to make it work. Also I don't know if you have a manual or automatic transmission? I know some people have issues with the automatic transmission when tuning these engines.

Thanks! Yeah later on i might get a m3 to. I have a manual RN. Thanks again!

 

Melvin,

I have tried to find that FB post I mentioned, but to no avail.
But I did find a 27-page slideshow of a fully illustrated N42 engine with see-through internals and everything. It may be useful when you plan your build.

BMW N42 engine

BMW N42 engine: attributes, technology, power and torque outputs, and models with this engine

australiancar.reviews

 

Thanks! This will be extremely useful! I think I am planning on building my engine next summer or so. I first need to fixe some rust and stuff.

 

Ahhh... rust, the killer of the tuning budget. I've been there.

Yeah, that's a neat slideshow. It was my first time seeing them all, pretty stoked to find them. Definitely helps me understand how the engine is put together.

 

Yeah! And it also helps with understanding basis maintenance good!

 

I found the guy's FB profile! It seems he has several recent posts regarding some advanced E46 tuning.
facebook.com/sjettegear

If you search his profile for 'N42' you will see a post dated Dec. 27 2020 about some of the parts. Apparently the pistons are from an Opel Omega. His ambition is to get 500 HP. The comments under that post contain a lot of useful details. Maybe that can point you in the right direction.

 

Thanks for the input fellow viking 💪🏽

 

This is the company that makes the compressor the FB guy wants to put on his engine. Anders Kolstrup, the company owner, is a Danish BMW tuning legend. There is an interesting interview with him on Youtube. Apparently he had early success building a twin turbo kit for the E34 M5.

 

Hi Daniel, it's always good to hear the words of someone with actual experience. I know nothing about engine tuning. By posting something here, I am simply sharing what I found, not endorsing any of it. Those two links do seem a bit generic and look like copies of each other.

Please share the results when your project is finished.

 

Will do for shure

I wasn´t going to blame you for the stupid websites, i just don´t like the misleading content

 

Hi Daniel,
Your MS4x wiki and software is great and easy to use.
Is there anything like that for N42 Siemens ME 9.2 too?
I also have an N42, besides two M54s, and looking for some info, read/write software and definition files for that DME. Unlike MS43, it's hard to find anything for this DME. I would like at least to delete secondary o2 sensor, like C_CONF_CAT disable on MS43.