01-16-2023, 03:29 PM | #1 |
New Member
4
Rep 10
Posts |
Limits and Recommended M240i Build
hey everyone, in the near future i'll be purchasing an LCI m240i and i just wanted to further understand some of the limits that the stock block and zf transmission can comfortably hold.
i plan on enjoying the car stock for a while but i definitely want to have the car to hold its own in a roll race for the summer the intention is to build a very capable daily driver while giving myself enough headroom so that the car doesn't explode on me. from what i've garnered the "sweet spot" with this power train is at around 550-600 whp before needing to build the block and trans. that being said i'm less concerned about the block than the trans, will an xhp stage 3 tune be enough for these kind of power limits? i don't intend on taking to the car to the dragstrip or launching often if barely at all. as for the components themselves id assume they looking something like this xhp stage 3 catless downpipe tu or better hpfp pure 800 turbo / docrace turbo kit (0 clue as to which turbo would suffice) i have access to e85, it's a bit far but i wouldn't have an issue driving to the station / buying a 55gal drum of e98 and mixing it myself. i don't necessarily want to cheap out but i also don't want to go overboard with headroom to eek out more power out of the stock block/trans appreciate any help given and i'm excited to join the platform soon |
01-16-2023, 05:39 PM | #2 | |
Major
1946
Rep 1,117
Posts |
Quote:
Also, there are some B58 enthusiast groups on Facebook. There are lots of people on there that are more into higher HP applications, upgraded turbo, and things like that. In my opinion you should be fine on stock internals and trans at the 550 to 600 HP levels but of course the stock turbo won't get you there so glad you are planning on replacement. The XHP stage 3 tune should work very well with what you are trying to do, and you can set torque limits by gear and the ranges are pretty vast. This will be especially important if you have a RWD version of the car. From your mods list I don't see the plan for engine tuning, what is the thought for that? MHD has worked great for me. Also, I recommend going with a a stage 2 HPFP (Dortch is a common one) vs the TU; that will allow more rail pressure and will be less limiting from an ethanal usage perspective.
__________________
2024 M2
2019 M240i- Sold |
|
Appreciate
0
|
01-16-2023, 09:26 PM | #3 | |
New Member
4
Rep 10
Posts |
Quote:
ive looked into vargas gc/gc+ turbos but i'm unsure about how they hold up and if i remember correctly they weren't the greatest choice for the n54. |
|
Appreciate
1
JMcLellan1945.50 |
01-17-2023, 07:55 AM | #4 |
Private
48
Rep 75
Posts |
If you’re planning to use bm3 or mhd be aware that if the car is on the 2019 software or later then you’ll need to get the dmc unlocked before you could use those tuning platforms, which means a visit to a tuner anyway - so you may as well just get it tuned when you’ve upgraded the components.
|
Appreciate
0
|
01-19-2023, 12:01 PM | #5 |
Major General
5488
Rep 5,336
Posts |
I'd definitely have $10K+ set aside for a rainy day repair if you plan on pushing 450whp+ on the stock block and transmission. It's easy to make big power, but the block wasn't designed for it nor was the 8AT. You can get away with for a little while, but in the long term, you'll likely be walking on egg shells. M models that push 420whp+ stock have a ton more cooling capacity than the M240. That's a big key to longevity and reliability. You just can't add a ton more power and not consider cooling.
Also, the earlier generation B58s, like those found in the M240, do have some issues with bore scoring, especially in modded B58s. If bore score happens, you'll need to replace the short block or sleeve it. Neither is cheap. Also pushing that amount of power definitely will require an LSD. With with stock power, the car needs an LSD. Assuming you install it yourself, you're looking at $2,500-3,000 depending the LSD you go with. If it were, me, I'd just get a prior gen M3/M4 that has all these parts already. With a very basic tune, it will be just as quick as a 500whp M240 and be more reliable and not for a lot more money. FYI, a 400-450whp/500wtq M240 will outrun a majority of the cars on the street. If it's an Xdrive, there's hardly any cars on the street that would hang with it from 0-90mph. My M235 6MT with ~380whp/400wtq is plenty quick for a street car and I very rarely wind it out thru 2nd and hardly ever 3rd as I'd be going over 100mph. These cars have such wide and long power bands that having "just 400whp" is misleading. It takes a Mustang Coyote 5.0 well over 450whp to hang with a 380-400whp turbo BMW 2/3 series. Power under the curve is key and why these cars haul serous ass.
__________________
The forest was shrinking, but the Trees kept voting for the Axe, for the Axe was clever and convinced the Trees that because his handle was made of wood, he was one of them.
|
Appreciate
1
Cos270608.50 |
01-19-2023, 12:31 PM | #6 |
Captain
334
Rep 998
Posts |
This guy set out to build a 1000HP B58 Supra. Did require some updated internals and various custom fabricated parts but he did it.
https://www.roadandtrack.com/new-car...-supra-engine/ And here is the original teardown (I think I got it from another thread here). It is a pretty beefy engine, I don't see 500HP being an outrageous ask from a stock short block. The ZF 8HP50 is another story though. I would not expect it to take that kind of power well at all. |
Appreciate
0
|
01-20-2023, 05:33 AM | #7 | ||
Colonel
1005
Rep 2,239
Posts
Drives: 2007 328i / 2014 M235i
Join Date: Nov 2017
Location: Ontario Canada
|
Quote:
Quote:
|
||
Appreciate
0
|
01-20-2023, 08:39 AM | #8 |
Major
1946
Rep 1,117
Posts |
I have the same interest in learning more about bore scoring. I googled it and couldn't find anything.
__________________
2024 M2
2019 M240i- Sold |
Appreciate
0
|
01-20-2023, 08:46 AM | #9 |
Lieutenant Colonel
2870
Rep 1,758
Posts |
It's more related to the plasma coating on the cylinder walls being washed away. Typically by fuel due to injector failure.
There's a few threads mentioning it on the 3 series side of the forums as well. |
Appreciate
0
|
01-20-2023, 09:55 AM | #10 |
Major
1946
Rep 1,117
Posts |
Ok. I went out and read a couple threads on this. There doesn't seem to be a strong relationship between modifications increasing the risk of this, but maybe the risk gets higher with using ethanol?? Replace injectors at 40K to 50K miles, or get a port injection system seem to be some viable solutions to reduce this risk.
__________________
2024 M2
2019 M240i- Sold |
Appreciate
0
|
01-20-2023, 12:38 PM | #11 | |
Major General
5488
Rep 5,336
Posts |
Quote:
Given that many people run high capacity HPFPs on their modded first gen B58s plus increased boost, thus way more fuel being pushed through the injectors, I do wonder if the stock injectors are being pushed past their limits and they start to leak. I know the S55 and S58 have the same plasma coating. I've never checked to see if they have the same injectors as the first gen B58 and/or if BMW has updated the injectors for the B58. I would not say this is a widespread issue, but it does seem to happen more in modded B58s than stock. I think if I were own one of these cars, I'd change the oil at least every 5K miles and do a used oil analysis to see if there is excessive fuel in the oil and high amounts of aluminum. If the issue does happen, you are looking at a 5 figure repair assuming you can't do the work yourself.
__________________
The forest was shrinking, but the Trees kept voting for the Axe, for the Axe was clever and convinced the Trees that because his handle was made of wood, he was one of them.
|
|
Appreciate
1
JMcLellan1945.50 |
01-20-2023, 12:45 PM | #12 |
Major General
5488
Rep 5,336
Posts |
The engine block itself if beefy with it's closed deck design, but when was the last time you heard of a N55 or N54 having block issues? The B58 has a forged crank and rods, but so does M235 and M2 N55 motor. When pushing big power through the B58 (or N55/N54), you do need to consider the fact that the fuel system, oiling systems, cooling systems, etc. weren't designed for that amount power thus you need to address that as well if you want the motor to last for the long term. The M cars have a ton more heat exchangers and upgraded fuel systems to handle the power and people expect a stock long block B58 to handle even more power than a stock S55
__________________
The forest was shrinking, but the Trees kept voting for the Axe, for the Axe was clever and convinced the Trees that because his handle was made of wood, he was one of them.
|
Appreciate
0
|
01-20-2023, 01:04 PM | #14 | |
Major
1946
Rep 1,117
Posts |
Quote:
I want to ask you: do you know if the injectors in Gen 1 and Gen 2 B58's are the same or are they different? To your point on using higher capacity HPFP (where I have a TU pump in my Gen 1 B58) I wonder if someone using a TU pump in their gen 1 B58 could benefit from having Gen 2 injectors if they are different.
__________________
2024 M2
2019 M240i- Sold |
|
Appreciate
0
|
01-20-2023, 01:12 PM | #15 |
Lieutenant Colonel
2870
Rep 1,758
Posts |
They are different part #s for 2nd gen injectors.
13538625396 (B58 in the F22) 13538656548 (B58 in the G29) 23209WAA01 (B58 in the Supra) looks like a different numbering system Last edited by freakystyly; 01-20-2023 at 01:17 PM.. |
Appreciate
0
|
01-20-2023, 01:47 PM | #16 |
Major
1946
Rep 1,117
Posts |
Cool. Thanks for sharing that. I looked on a few product sites and none of them list these as fitting with a Gen 1 B58 so perhaps my idea doesn't matter. Hmm
__________________
2024 M2
2019 M240i- Sold |
Appreciate
0
|
01-20-2023, 08:14 PM | #17 | |
New Member
4
Rep 10
Posts |
Quote:
|
|
Appreciate
0
|
01-20-2023, 10:07 PM | #18 | |
New Member
4
Rep 10
Posts |
Quote:
also, funny you mention a coyote engine, my friend has an fbo one and beats nearly anything that comes his way and my target is to be faster than him |
|
Appreciate
0
|
Post Reply |
Bookmarks |
Thread Tools | Search this Thread |
|
|