[verfum]

Hi
I just purchased an M140i (2017) to replace my old 2004 E85 Z4 3.0i and I'm a bit disappointed in its initial acceleration.
From standing to about 15mph the Z4 is more responsive. Could this be it is lighter?
After the 140 turbo kicks in, it destroys the Z4.
But pulling out of junctions, particularly on a hill, the Z4 is much nippier.
Am I missing something? - I have tried sports and sports plus modes but Z4 has the edge until the M140 turbo kicks in.
I'm guessing at low revs they are both 3 litre and pretty equal, so difference is inertia in the fact the Z4 is lighter?
Is this normal?

 

[Jambo87]

Manual or auto?

 

[muon]

The M140i has way more torque across the entire rev range. No way the Z4 would be quicker 0-15 if both launched properly.

 

[140ifan]

Hi
I just purchased an M140i (2017) to replace my old 2004 E85 Z4 3.0i and I'm a bit disappointed in its initial acceleration.
From standing to about 15mph the Z4 is more responsive. Could this be it is lighter?
After the 140 turbo kicks in, it destroys the Z4.
But pulling out of junctions, particularly on a hill, the Z4 is much nippier.
Am I missing something? - I have tried sports and sports plus modes but Z4 has the edge until the M140 turbo kicks in.
I'm guessing at low revs they are both 3 litre and pretty equal, so difference is inertia in the fact the Z4 is lighter?
Is this normal?

M140i is a turbo, the z4 is NA

NA will ALWAYS be more responsive than a turbo car, the turbo has to build boost, once its done that though it will eat it alive. Launch control may help build the boost prior to launch but put a LOT of stress on the drivetrain.

Just accept it for what it is, ragging it from 0 to 15 is hard on the car anyway.

 

[padders]

Could be traction related. A well sorted M-lite should eat a z4 for breakfast at every speed inc standstill. Maybe try with the tc off entirely and see if you get a very different result, that would suggest your tyres are to blame. That and the lack of LSD. The tc on modern BMWs comes in very early and subtly and you might not even realise it is acting to slow you as it is preemptive.

 

[OneTwenty]

Something not right there.

My 240 has such ferocious launch/pickup that I don't think I've been in anything that can match it off the line, including a Z4!! They have 500nm torque in stock form and that comes in at just 1500rpm IIRC.

However, if you have the stock MPSS tyres fitted that can give you an initial bogging down in my experience that causes a slight delay when leaving junctions, especially in wet or cold weather.

 

[OneTwenty]

Hi
I just purchased an M140i (2017) to replace my old 2004 E85 Z4 3.0i and I'm a bit disappointed in its initial acceleration.
From standing to about 15mph the Z4 is more responsive. Could this be it is lighter?
After the 140 turbo kicks in, it destroys the Z4.
But pulling out of junctions, particularly on a hill, the Z4 is much nippier.
Am I missing something? - I have tried sports and sports plus modes but Z4 has the edge until the M140 turbo kicks in.
I'm guessing at low revs they are both 3 litre and pretty equal, so difference is inertia in the fact the Z4 is lighter?
Is this normal?

M140i is a turbo, the z4 is NA

NA will ALWAYS be more responsive than a turbo car, the turbo has to build boost, once its done that though it will eat it alive. Launch control may help build the boost prior to launch but put a LOT of stress on the drivetrain.

Just accept it for what it is, ragging it from 0 to 15 is hard on the car anyway.

That may have been true in the 80s/90s when turbo cars had huge turbo lag, but the pickup on these is pretty much instant now due to the smaller turbo.

I don't believe a modern NA car will be more responsive than a modern turbo car, especially a 3L torque monster.

 

[OneTwenty]

It could also be that the Z4 has a traditional cable throttle (not sure if it does or not???), and the MLites are drive by wire.

Older cable throttle cars will be more responsive than modern cars.

But any 140/240 should be killing an NA Z4 from 0 to anything, not reliant on the turbo, which kicks in early anyway.

 

[barneym140i]

are you driving with full traction on? never had issues in my old m140i in traction or sport plus mode

In fact after an Xhp map it was even better and extremely quick off the mark, very impressive

 

[padders]

Hi
I just purchased an M140i (2017) to replace my old 2004 E85 Z4 3.0i and I'm a bit disappointed in its initial acceleration.
From standing to about 15mph the Z4 is more responsive. Could this be it is lighter?
After the 140 turbo kicks in, it destroys the Z4.
But pulling out of junctions, particularly on a hill, the Z4 is much nippier.
Am I missing something? - I have tried sports and sports plus modes but Z4 has the edge until the M140 turbo kicks in.
I'm guessing at low revs they are both 3 litre and pretty equal, so difference is inertia in the fact the Z4 is lighter?
Is this normal?

M140i is a turbo, the z4 is NA

NA will ALWAYS be more responsive than a turbo car, the turbo has to build boost, once its done that though it will eat it alive. Launch control may help build the boost prior to launch but put a LOT of stress on the drivetrain.

Just accept it for what it is, ragging it from 0 to 15 is hard on the car anyway.

That may have been true in the 80s/90s when turbo cars had huge turbo lag, but the pickup on these is pretty much instant now due to the smaller turbo.

I don't believe a modern NA car will be more responsive than a modern turbo car, especially a 3L torque monster.

Totally agree. You'd have to force the B58 to pull in a very high gear at very low revs to experience anything like lag and in an auto it is virtually impossible unless you force it with the paddles. I regularly swap between a 3.6l 911 and my M240i and the BMW is noticeably stronger everywhere in the rev range, you have to rag the 911 to get it to fly (which is fun of course), whereas the BMW just goes and goes. The 911 weighs about the same as the z4 so I have a hard time thinking it is the turbo to blame here. My money is on either lack of traction or a poorly engine.

 

[tweeky]

try resetting the throttle.

 

[Jamesthesecond]

Small boost leak perhaps? Maybe something as silly as the air filter housing not being shut fully.

 

[MSM]

Maybe dme torque limiting in the lowest gears could be contributing to bogging the car down. Sounds a bit more like traction control kicking in though.

 

[AngloSaxon]

From standing to about 15mph the Z4 is more responsive.

ARe you sure the M140i isn't still wheel spinning? :lol: :lol:

 

[markm240i]

I always thought the m240i and M140i autos could feel sluggish from initial take off unless you were quite aggressive with the throttle, but not to the point where you lose traction. The ZF8 is a fantastic gearbox once the transmission locks, but it can't initially hide the fact it's a slushbox torque converter.

WRT to the turbo kicking in, the B58 is pushing 500Nm from ~ 1750 RPM so even if it's torque limited in the lower gears (I don't know) it really shouldn't be an issue.

If it's a manual I've no idea what the problem might be!

 

[mlcman]

As a new owner of a M140i Auto xDrive I think I understand what the OP is about. Assuming he is talking ordinary take-off (ie. not launching and not in very high revs, just trying to make swift progress) there is what feels like a small hesitation from the engine to rev/accelerate, which becomes more noticeable due to the engine sounding as if it's being stressed more than it would like.

Funny thing is that it's really happening on the very first part of the acceleration though and goes away after a bit of speed is built. It's definitely not turbo lag, that's quite different, but rather non-optimal gearbox/map tuning for those conditions of low speed acceleration in 1st gear rather than an actual issue.

I noticed this as I got hold of my car just a few days ago, so the difference in setting off compared to my other cars was evident, even though the M140i smokes all of them and has huge torque to spare, even more so due to the fact it runs MHD Stage 1 and xHP stage 3 on the ZF.

But I immediately got what the OP was describing (or at least I think I did )

 

[OneTwenty]

It's certainly something that is present on the cars with a ZF box, when using the stock tyres, and more in wet/cold weather.

But when I switched to PS4, and now PS5 it pretty much disappeared altogether. It can be slower to accelerate in Comfort mode when leaving junctions, but if I know I want to get away quicker I normally have it in Sport anyway, and there is no delay in Sport or Sport+.

Tyres can make a huge difference to it.

 

[docwra]

I don't believe a modern NA car will be more responsive than a modern turbo car, especially a 3L torque monster.

Ive got a 2ZZ and an LS7 on the drive, I can assure you they are - its a pleasure to drive both after some fuzzy throttled FI thing

As far as the delay is concerned ....... I reckon its probably built into the car - BMW have always liked a clutch delay valve, or a bit of throttle smoothing and their auto boxes have never been the fastest to pick up - nice to drive but more of a scythe than a scalpel.
Maybe look into a map, maybe just get used to it?

 

[OneTwenty]

What the hell have you done there docwra, I can't even work out who said what with that, or what the reply even is etc. :lol:

 

[docwra]

Fixed it for you :lol:

The LS7 particularly has restored my love for NA, modern turbo cars are so well engineered that you forget there will always be a slight delay in response, its really nice to get back in something where your foot feels directly connected to the throttle plate