Let’s Torque Curves

[Jonhklee]

Standard torque and BHP curve of M139. Do we think Lotus will alter that much?

Looks like the engine revs over 7k rpm but dips towards the end of rev range…..that flat torque curve will make it feel a sledge hammer at any speed!! Can’t wait

 

[ADC]

View attachment 4124
Standard torque and BHP curve of M139. Do we think Lotus will alter that much?

Looks like the engine revs over 7k rpm but dips towards the end of rev range…..that flat torque curve will make it feel a sledge hammer at any speed!! Can’t wait

Still blows my mind that these are curves for a 2 litre four pot, and not the v8s I used to drool over as a youngster...

 

[Jonhklee]

Still blows my mind that these are curves for a 2 litre four pot, and not the v8s I used to drool over as a youngster...

With 30psi boost nonetheless

 

[Leonard]

Still blows my mind that these are curves for a 2 litre four pot, and not the v8s I used to drool over as a youngster...

I used to love my EVOs so 400bhp ball bearing turbo with a linear curve is the norm. 850bhp with a big turbo and some more punch is fun also

 

[ADC]

I used to love my EVOs so 400bhp ball bearing turbo with a linear curve is the norm. 850bhp with a big turbo and some more punch is fun also

I do vividly recall a ride as a passenger in an Evo 3 of that caliber, driven by a friend of a friend (i.e. barely knew the guy) ... Equal parts awesome and terrifying

 

[Leonard]

I do vividly recall a ride as a passenger in an Evo 3 of that caliber, driven by a friend of a friend (i.e. barely knew the guy) ... Equal parts awesome and terrifying

Such great cars, remember passengering with friends and feeling very sick after a couple of laps And my mates 7mins 50sec at the Nurburgring is best forgotten

 

[ADC]

Speaking to the original line of questioning, my understanding is that Lotus will have tuned for linearity, so I reckon the curves wont be far off that shape, just peaked lower.

 

[Leonard]

Speaking to the original line of questioning, my understanding is that Lotus will have tuned for linearity, so I reckon the curves wont be far off that shape, just peaked lower.

You would think it would be tuned for zero lag and maximum power accross the rev range #NAfeel

 

[Eagle7]

You would think it would be tuned for zero lag and maximum power accross the rev range #NAfeel

I think some of that would depend on what they're able to get through homologation.

 

[Singularity]

I think some of that would depend on what they're able to get through homologation.

I’m running the M133 variant of the engine and I can confirm the thing pulls like a rocket above 2500. I generally shift down around 5500 myself and the DCT doesn’t go above 6000 even in the aggressive settings.

Given Lotus are working well within the engine capabilities in terms of both power and torque (the stated values for the M139 in the I4 are even less than the older M133 I have), then they have quite a bit of scope to play with the torque curve profile.

However, as @Eagle7 points out Lotus have to meet all the homologation requirements including emissions emissions et al (internationally) and, while AMG already do that for the A45 (and the M139 is going in the C63 too), who knows what the repackaging will have done with how the engine breathes. Set against that the Emira is much lighter than and A45 which will help with both economy and emissions, so I guess we’ll just have to wait and see.

I still suspect the i4 is being deliberately tuned at launch to make sure it doesn’t eclipse the V6 in performance and I quite understand that. Even though the differentiator for the two models is really the manual gearbox and sound, I think a full fat i4 (torque and power) and DCT in a 1400kg car would dilute the ‘last analogue Lotus’ marketing strategy. I just hope that the inevitable future mapping upgrades are available as a retrofit for us early i4 adopters!

 

[denk0815]

I’m running the M133 variant of the engine and I can confirm the thing pulls like a rocket above 2500. I generally shift down around 5500 myself and the DCT doesn’t go above 6000 even in the aggressive settings.

Given Lotus are working well within the engine capabilities in terms of both power and torque (the stated values for the M139 in the I4 are even less than the older M133 I have), then they have quite a bit of scope to play with the torque curve profile.

However, as @Eagle7 points out Lotus have to meet all the homologation requirements including emissions emissions et al (internationally) and, while AMG already do that for the A45 (and the M139 is going in the C63 too), who knows what the repackaging will have done with how the engine breathes. Set against that the Emira is much lighter than and A45 which will help with both economy and emissions, so I guess we’ll just have to wait and see.

I still suspect the i4 is being deliberately tuned at launch to make sure it doesn’t eclipse the V6 in performance and I quite understand that. Even though the differentiator for the two models is really the manual gearbox and sound, I think a full fat i4 (torque and power) and DCT in a 1400kg car would dilute the ‘last analogue Lotus’ marketing strategy. I just hope that the inevitable future mapping upgrades are available as a retrofit for us early i4 adopters!

Yes, we can only hope so.
Last week I was already thinking about whether I shouldn't rather do without the FE and buy the first version of the i4 with remapping. But in the meantime I think that this will probably only be offered after three years anyway and by then the warranty of the FE will have expired and I can remapping myself.

 

[Persad12]

Yes, we can only hope so.
Last week I was already thinking about whether I shouldn't rather do without the FE and buy the first version of the i4 with remapping. But in the meantime I think that this will probably only be offered after three years anyway and by then the warranty of the FE will have expired and I can remapping myself.

Considering this packaging is coming from mercedes and we all know what that engine is capable of. First edition models shouldnt be that hard to tune for more power. The elise and exige were both very tunable cars when there was room for more power. The evora GT and 400 were already close to its mechanical limit especially the trans. Even with the locked ECU not many tuners were interested in this platform because there wasnt much power to be gained. But the I4 will definitely attract more tuners especially ones who have already worked with the m139.

 

[Porter]

Considering this packaging is coming from mercedes and we all know what that engine is capable of. First edition models shouldnt be that hard to tune for more power. The elise and exige were both very tunable cars when there was room for more power. The evora GT and 400 were already close to its mechanical limit especially the trans. Even with the locked ECU not many tuners were interested in this platform because there wasnt much power to be gained. But the I4 will definitely attract more tuners especially ones who have already worked with the m139.

We shouldn't assume that the M139 will use the same engine management system in the Emira that is used in the Mercedes cars. It's possible that it's a unique implementation all the way around. I think it remains to be seen.

 

[3MIRA]

I’m running the M133 variant of the engine and I can confirm the thing pulls like a rocket above 2500. I generally shift down around 5500 myself and the DCT doesn’t go above 6000 even in the aggressive settings.

Given Lotus are working well within the engine capabilities in terms of both power and torque (the stated values for the M139 in the I4 are even less than the older M133 I have), then they have quite a bit of scope to play with the torque curve profile.

However, as @Eagle7 points out Lotus have to meet all the homologation requirements including emissions emissions et al (internationally) and, while AMG already do that for the A45 (and the M139 is going in the C63 too), who knows what the repackaging will have done with how the engine breathes. Set against that the Emira is much lighter than and A45 which will help with both economy and emissions, so I guess we’ll just have to wait and see.

I still suspect the i4 is being deliberately tuned at launch to make sure it doesn’t eclipse the V6 in performance and I quite understand that. Even though the differentiator for the two models is really the manual gearbox and sound, I think a full fat i4 (torque and power) and DCT in a 1400kg car would dilute the ‘last analogue Lotus’ marketing strategy. I just hope that the inevitable future mapping upgrades are available as a retrofit for us early i4 adopters!

your not wrong!