[lex97h]

BMW is known for underrating horsepower. With that said, anyone ever dyno a 2022 X3/X4 and see if it is indeed 382HP at the crank? Or is it 400 as some say?

[ASAP]

i too would be curious to see a dynojet dyno on a 22+ m40i

[ContactPatch]

This is widely discussed and common knowledge with in the B58 community: ultimately, the B58 engine makes roughly their crank horsepower rating at the wheels. Not to shabby at all, no wonder everyone adores this powerful engine!

[lex97h]

Factoring a 10 to 20% power loss from crank to wheel so the B58 makes roughly between 420 to 450 HP at the crank? That is impressive.

[g11hoonigan]

It's bmw. The HP / tq numbers on paper is pretty much what you'd measure at the wheels, give or take a few hp (variance).

[glennbk]

Originally Posted by g11hoonigan

It's bmw. The HP / tq numbers on paper is pretty much what you'd measure at the wheels, give or take a few hp (variance).

I surmise they do that for insurance purposes. Again, any vehicle over 400 horsepower is treated as a "muscle car" by insurance actuaries.

[Rottweiler]

Originally Posted by g11hoonigan

It's bmw. The HP / tq numbers on paper is pretty much what you'd measure at the wheels, give or take a few hp (variance).

I surmise they do that for insurance purposes. Again, any vehicle over 400 horsepower is treated as a "muscle car" by insurance actuaries.

Are you certain of this…the 400 hp threshold for insurance companies?

Also, “surmise” was last used by the primary evil character (w/ really bad teeth and bulimia) in Season 3 of Fargo on FX

Season 1 of same was horribly weak. Season 2 was the best; excellent. Season 3 was very good, and Season 4 was sadly poor

[glennbk]

Do I have direct proof? No. Do I have people I know whom work as actuaries at insurance companies and set standards/price floors for tiered pricing based upon engine power output, yes. Every single one has stated ten years ago, 300 hp was a thresh hold mark. It has steadily crept up to 400 hp, due to newer technology and the simple fact there are 4 cylinder engines now making over 300 hp. Newer engines, especially those using the Chrysler/Stellantis 3.0 liter Inline 6, have a muscle car designation. I'd be willing to guarantee BMW went to great lengths to keep as many engines as possible outside of that category.

[Rottweiler]

👏👏👏

Thank you

[glennbk]

Let's face facts. It has nothing to do with safety, rather making money. There are a lot of "assumptions" made about people driving a "muscle car". Overly aggressive, speeding, getting tickets, causing car accidents, performing street takeovers and the list goes on. My insurance company heavily pushed for a monitoring service to get me a "discount". I tried it for two weeks and found the results were wildly inaccurate. When confronted, they admitted that there are bugs in the software and G-meter detector. That ended that experiment. They were nice enough to give me a 10% discount for the remainder of my 6 month policy.

[Keefy]

Would anyone happen to know the realistic HP & torque figures for the M40d....long-shot I know as all you guys are in North America.....I feel the torque, it's insane, just wondered if the same BMW underrating of the figures would also apply to their diesel variants? I assume it would?

[g11hoonigan]

Originally Posted by Keefy

Would anyone happen to know the realistic HP & torque figures for the M40d....long-shot I know as all you guys are in North America.....I feel the torque, it's insane, just wondered if the same BMW underrating of the figures would also apply to their diesel variants? I assume it would?

I don't have any info but I have no doubt in my bone that it's tested the same way as the petrol models.

[glennbk]

That's a good question. If I were betting, I'd say a tune would raise the horsepower to 420, but the torque would easily be over 600 lb-ft. Dinan says, "Up to 30 HP, 50 lb-ft of torque".

B57D30S0 2016–2020
294 kW (394 hp) at 4,400 rpm
760 N⋅m (561 lb⋅ft) at 2,000–3,000 rpm
---the new engine allows for 0-100kph in 5.6 seconds

https://en.wikipedia.org/wiki/BMW_B57

[Keefy]

Originally Posted by glennbk

That's a good question. If I were betting, I'd say a tune would raise the horsepower to 420, but the torque would easily be over 600 lb-ft. Dinan says, "Up to 30 HP, 50 lb-ft of torque".

B57D30S0 2016–2020
294 kW (394 hp) at 4,400 rpm
760 N⋅m (561 lb⋅ft) at 2,000–3,000 rpm
---the new engine allows for 0-100kph in 5.6 seconds

https://en.wikipedia.org/wiki/BMW_B57

BMW states 0-100kph 4.9.(must admit it feels a bit quicker than that, I should use my draggy box and compare) The torque is where its at for me, I'm not really interested in the top end speed as tends to put you in prison over here but certainly enjoy getting from zero up to legal (ish) speeds quickly....so the torque certainly plays its part there.

https://www.car.info/en-se/bmw/x3/x3...25478111/specs

[glennbk]

Lets face facts. You could add a bunch of updates and totally light up your tires with oodles of torque. But, is it really what you want? Plus, you have that pesky MOT testing. I can't see you passing testing, as NOx emissions would be affected. I agree, you have an awesome car. And, it is sad that diesel in passenger vehicles is all but dead in the USA.

[Keefy]

Originally Posted by glennbk

Lets face facts. You could add a bunch of updates and totally light up your tires with oodles of torque. But, is it really what you want? Plus, you have that pesky MOT testing. I can't see you passing testing, as NOx emissions would be affected. I agree, you have an awesome car. And, it is sad that diesel in passenger vehicles is all but dead in the USA.

Unsure if your post was directed at me but the car that I have, the M40d will pass MOT testing as its unmodified in terms of engine and or exhaust, so there is no reason for it to fail.

The MOT is also not done until year 3 over here, so I've got many many pleasurable miles to go before it goes through a routine MOT test that the car was designed to pass in the first place, so all good.

Perhaps later on in its life if the car was poorly maintained etc with emissions, but I take care of my possessions especially a £65k car so I'm not worried at all if I'm honest.

[glennbk]

Right. I was suggesting a performance mod could change that.

[Keefy]

Originally Posted by glennbk

Right. I was suggesting a performance mod could change that.

I did all the modifications thing in terms of engine and exhaust tuning in my last car, Golf R and had my fun, so I guess I'll be keeping my m40d relatively stock with some cosmetic changes to the exterior and my throttle response box but other than that, it'll remain standard as I want to keep the warranty

[satz]

Has anyone actually tested a B58 in exactly the same way that BMW would have done? I'd be curious then to see how much BMW really under-reports its output.

I've heard this for years that BMW under-reports its engine output (b58, N54 engine and others).....but wondered why. In terms of marketing it doesn't make sense (and yes, I've also read that they don't want to show how close the M40's power is really to an X3M for example...)

To me it would be very hard to say by 'feel' whether your engine is outputting more than spec. Too many variables. The stupid 'learning' throttle for example makes my M40 feel like a 3-legged dog sometimes, but at other times it feels much more powerful...

[glennbk]

I think they under estimate the numbers for insurance purposes. As for testing, there have been a number of dyno videos on Youtube but nothing from an agency or car magazine...that i'm aware of.

[Keefy]

A few interesting videos, obviously the OEM quoted figures and the dyno figures will always differ due to ambient temp, type of dyno used, fuel load and spec, weight, age of the vehicles used, in fact there are so many variables its hard to compare really, and we don't know how the OEM's are testing their vehicles but interesting videos none the less.

[Jason73]

https://bimmerlife.com/2020/05/16/re...an-advertised/

https://www.bmwblog.com/2019/09/19/u...und%20381%20HP.

2 articles showing the actual dyno wheel HP of the B58 engine is in the 380-390 range. So the 382 BMW number does appear to be wheel HP not crank. Well over 400HP at the crank, 425-440.