[M340i Touring Xdrive]

Hi all,

I am new to this forum and just purchased a BMW M340i (gen 2 B58) touring xdrive (11/2020) and want to tune it.

Apologies if my English is not perfect and thanks in advance for responses!

I want to get a lot out of the tune, as long as the car is comfortable to drive on a daily basis and while maintaining reliability, as I expect to drive the car for 3 - 5 years. No meth/ethanol, I will only fill up with ron 98 (93 usa) gasoline.

I am very curious about your advice and have already checked a few things out.

Stage 1/2 option: (200 cell) catted downpipe, midpipe (OPF removal), ECU and xhp tune: approximately 450HP 650NM

Stage 2+/3: stage 1/2 mods + intake, eventuri?, hybrid turbo, Pure turbo 800/850?: approximately 550HP 750NM?

Other options worth considering?
- Intake manifold, Wagner?
- Charge pipe?
- Any other upgrades (also in relation to reliability)?

Finally, a question regarding rims and tires:
The BMW now has 791M 19-inch rims with 225/255 RF Pirelli Zero tires. I am considering using the rims as a winter set and purchasing a new 795M forged 20 inch (225/255) set.
They are beautiful (and lighter), but is it also wise to put them underneath or is it too much at the expense of grip (and comfort)? Possibly with Continental Sport Contact 7 tires instead of the p-zero RFs?

[mike@x-ph.com]

It sounds like you already have done your research and know what you need. It a just a matter of deciding whether you want to get an upgraded turbo or not.

[M340i Touring Xdrive]

That's true, but it's not yet clear to me if that's a proper upgrade for a daily driver. It is obviously more power, but I also read more turbo lag and that there is only a lot of torque available from 3000pm vs 2000+ rpm stock turbo. Does this have a negative impact on everyday driving pleasure?

And it is not yet clear to me whether and from which tune a heatexchanger and/or intake manifold is a needed upgrade.

[RTPenland]

If your stated goal is accurate:
I want to get a lot out of the tune, as long as the car is comfortable to drive on a daily basis and while maintaining reliability,

If it were me, I would run E30, a DP through the stock exhaust, and a quality flash. This should net you in the neighborhood of 525 reliable crank HP.

I would only go to a bigger turbo and custom tune, if I was also going to address fueling issues and at that point I think you start to sacrifice some of your stated goals

That being said you don't need to boil the ocean on your first attempt, DP, E30, Flash live with it drive it and if it's not enough build on that foundation and plot your next move

[Elderado82]

As stated above, if you're not planning to exceed 475 to 500 hp, stick with the stock turbo. If you aim for 750 to 800 hp, you'll need to add modifications for fuel and cooling, as the stock fuel and cooling systems fall short in those power ranges. Also, note that the transmission is rated for 600 lb-ft of torque, so be careful when exceeding this limit, especially when reaching 750+ hp. If you do, it's recommended to invest in a built transmission.

[M340i Touring Xdrive]

Originally Posted by RTPenland

If your stated goal is accurate:
I want to get a lot out of the tune, as long as the car is comfortable to drive on a daily basis and while maintaining reliability,

If it were me, I would run E30, a DP through the stock exhaust, and a quality flash. This should net you in the neighborhood of 525 reliable crank HP.

I would only go to a bigger turbo and custom tune, if I was also going to address fueling issues and at that point I think you start to sacrifice some of your stated goals

That being said you don't need to boil the ocean on your first attempt, DP, E30, Flash live with it drive it and if it's not enough build on that foundation and plot your next move

Unfortunately E30 fuel is not an option for me, I will only be able to fill up with 98 (93) fuel.

It is indeed a consideration to keep the stock turbo and possibly replace the turbo later. However, this will be more expensive, because the ECU (and possibly XHP) will have to be tuned twice.

[M340i Touring Xdrive]

Originally Posted by Elderado82

As stated above, if you're not planning to exceed 475 to 500 hp, stick with the stock turbo. If you aim for 750 to 800 hp, you'll need to add modifications for fuel and cooling, as the stock fuel and cooling systems fall short in those power ranges. Also, note that the transmission is rated for 600 lb-ft of torque, so be careful when exceeding this limit, especially when reaching 750+ hp. If you do, it's recommended to invest in a built transmission.

Okay, thanks! Well I would love to exceed 475/500 hp, but I am not aiming for 750+ hp. My goal would be 550whp and 750NM (550 lb-ft) of torque on 98 (93) pump gas.

If I understand correctly, I remain within the safe margins and upgrades regarding cooling are not necessary, correct?

I might consider purchasing a heat exchanger, that will improve reliability.

So the only way to achieve 550whp on pump gas is to go for a (hybrid) turbo upgrade.

The setup would then be:
- Pure 800 (or another?)
- 200 cell downpipe
- Midpipe (OPF removal) or (even better) a full cat back exhaust
- Intake (Eventuri)
- ECU and XHP tune
- Optional: Heat exchanger
- Anything else?

The only real question that remains with this tune concerns daily use. Does it remain a nice setup for "normal" daily use, or is a turbo upgrade not recommended?

Thanks in advance.

[Matic94]

I would not recommend a heat exchanger, it is definitely not worth the money. If you are going to do any cooling mods, it should be an intake manifold.

[kfer]

Originally Posted by M340i Touring Xdrive

Okay, thanks! Well I would love to exceed 475/500 hp, but I am not aiming for 750+ hp. My goal would be 550whp and 750NM (550 lb-ft) of torque on 98 (93) pump gas.

Your problem will be the RON98. So you certainly can't get into the "desired" range without Ethanol or WMI. But 550hp would maybe possible at the crank.

If I were you, I would first choose a Platform (MHD, BM3, MGFlasher or similar) and then flash a Stage 1 (first of course DME Unlock at Femto).
This should get you to ~450hp (crank). Then I would install downpipe and go to Stage2 (that would be around 470-480hp).
Only then would I think about whether an upgrade turbo is necessary or not.
Since you're from Europe, I would also consider Turbosystems' turbos (https://www.turbosystems.info/produc...e-turbocharger).
If you already have an upgrade turbo, you will also need a custom tune.
A charge pipe would be also good for the increased boost.

Regarding the downpipe, you should clarify if the emissions test is possible with CPI 200 or not. (I have CPI300 from HJS on my 40i and it meets EU6d).
The same applies to OPF delete. As far as I know, the particles for gasoline engines are not yet measured in Europe (only for diesels) , but it will come. With OPF you can land in the 550hp range (with RON98 more like 520-530).
If for you "daily" means that everything is dismantled before the emissions test, then forget what I wrote above.
If you throw everything out (Catless+OPF delete), then around 580-600hp is possible with RON98 (without ethanol or WMI).

[Cpatel]

Originally Posted by mike@x-ph.com

It sounds like you already have done your research and know what you need. It a just a matter of deciding whether you want to get an upgraded turbo or not.

If I were to upgrade turbo, would I need to get a custom map to utilize that or would a bootmod OTS stage 2 map be enough?

[jpowers36]

You won’t see any benefits from the big turbo without a custom tune. I’d recommend one. OTS maps are for OEM hardware or cars that have just basic bolt ons. If/when my stock turbo goes, I’ll more than likely go Pure800. Then get a custom tune with MG Flasher since I’m currently running their stage 2 OTS 93 tune. I’d like to eventually go EcuTek, port injection, full e85. That’s another few grand though. EcuTek also needs to fix the remote start feature lol.

[M340i Touring Xdrive]

Originally Posted by Matic94

I would not recommend a heat exchanger, it is definitely not worth the money. If you are going to do any cooling mods, it should be an intake manifold.

Good to know thanks!

They promise reasonable cooling compared to stock, but that turns out not to be the case, do you have a negative experience with it?

[M340i Touring Xdrive]

Originally Posted by kfer

Your problem will be the RON98. So you certainly can't get into the "desired" range without Ethanol or WMI. But 550hp would maybe possible at the crank.

If I were you, I would first choose a Platform (MHD, BM3, MGFlasher or similar) and then flash a Stage 1 (first of course DME Unlock at Femto).
This should get you to ~450hp (crank). Then I would install downpipe and go to Stage2 (that would be around 470-480hp).
Only then would I think about whether an upgrade turbo is necessary or not.
Since you're from Europe, I would also consider Turbosystems' turbos (https://www.turbosystems.info/produc...e-turbocharger).
If you already have an upgrade turbo, you will also need a custom tune.
A charge pipe would be also good for the increased boost.

Regarding the downpipe, you should clarify if the emissions test is possible with CPI 200 or not. (I have CPI300 from HJS on my 40i and it meets EU6d).
The same applies to OPF delete. As far as I know, the particles for gasoline engines are not yet measured in Europe (only for diesels) , but it will come. With OPF you can land in the 550hp range (with RON98 more like 520-530).
If for you "daily" means that everything is dismantled before the emissions test, then forget what I wrote above.
If you throw everything out (Catless+OPF delete), then around 580-600hp is possible with RON98 (without ethanol or WMI).

That can be a useful approach.
I have good experiences with Mosselman Turbo systems (Netherlands) and since I live there Pure Turbo (Belgium) could also be an option.

I want to have the OPF removed, but I will opt for a catted downpipe because of the smell from a catless DP.

[Davg31]

Hi, I'm in Belgium and also in 98, BM3 and Downpipe with KN, I'm at +- 480 hp and 700 torque.

[M340i Touring Xdrive]

Originally Posted by Davg31

Hi, I'm in Belgium and also in 98, BM3 and Downpipe with KN, I'm at +- 480 hp and 700 torque.

Nice! At the crank or wheels?

[M340i Touring Xdrive]

Anyone else have some thoughts about a heat exchanger or intake manifold, especialy regarding reliability?

Thanks in advance.

[pdxtiger]

I can't see any reason you'd need to mess with the cooling system if you're running stock turbo on a street car on pump gas in the Netherlands. Run logs and see if it's necessary first or you're pissing money away.