Did lotus rob us on horsepower?

[Eagle7]

Those speeds are just silly for this car, even though it can do it. What was their fuel consumption, 5 mpg?

 

[Tracked Emira]

Agreed. To each their own. I didn’t expect such a strong reaction to my comment.

You walk past a big mirror and say....What are you looking at!?...And you're like...Ohhh, it's just me

 

[Beachbum]

Not watched either video, at work and they frown on that sort of thing However if all they are using is the car Speedo, then the chances of that being 100% accurate are almost zero. By the time you get above 100mph, most speedo's have an error factor of at least +/- 5% and over 150mph its usually a lot more. Its usually on the plus side

 

[hellasf1]

You can do all the weight saving out there but at the end of the day if you want the Emira to deliver what you think it should being as exotic looking car, you will need to add more power IMO! I think the sweet spot is JUBU 460 Kit with all weight saving you can do. If you have the money I think the JUBU 500 is absolutely perfect!

I loved the Emira in many aspect but 1 main concern when I test drove it. It’s not a fast car. People that tell you it’s fast, haven’t had fast cars. It’s quick yes and it’s plenty for most, which is why Lotus gave it what it did. They are not wrong since people are buying them and loving it. But the cost your paying isn’t for the power and I think we can all agree on this, do we wish we all were given more yes obviously lol!

That being said when I placed my order I knew I would be upgrading the power and I have already gone with the JUBU 440 kit. Absolutely love it has a launch control and raising the rpm to 7,200 was also a need since I felt it cut power sooner than the claimed 6,800 (others have said the same thing so it’s not wrong, some just are more in tune with what’s going on than others) The way I have my car set up now is how the car “power wise” should have come from the factory. So to me I am where I should have been stock, so I do plan on further stages soon probably the end all be all for me is the JUBU 500 with forged internals down the road.

I know these stages will cost money but at the end of the day I will pay just over what a manual GT4 would cost me (new as I would spec before I lost my allocation since they discontinued it)
and I will have more power, better handling (with some more mods) way better looking/special looking car and better sounding.

It cost less to go with JUBU 460 then do all the weight savings. So how I structured my build is 440 JUBU with some weight saving small items exhaust and battery, next is 460 JUBU then all other impactful weight saving mods like wheels and seats etc.
I think with this I will be really happy for awhile bc I would have saved around 130-150 lbs give or take depending what I choose, and ill be at minimum 460 hp as the tune only restricts tq so depending on my specific engine I could be at 475-490 according to JUBU. I would do a dyno at some point to see my numbers and my tq is limited at max 369 lb/ft until I do the 500 kit.

That’s my plan doesn’t have to be yours, make it your own, be honest in what you want out of your car realistically with your budget and needs, make a plan to get there dont stress and enjoy driving the car in the process and don’t wait till the “build” is done bc we all know it’s never done lol. Stay in present, enjoy the journey and have fun!

 

[Jinba ittai]

You walk past a big mirror and say....What are you looking at!?...And you're like...Ohhh, it's just me

Ha! Or I’m just trying to keep the forum positive. If I inadvertently offend a snowflake I’ll try to walk it back. Pretty sure I’m being trolled now though so I’m done.

 

[CarGuy11]

You can do all the weight saving out there but at the end of the day if you want the Emira to deliver what you think it should being as exotic looking car, you will need to add more power IMO! I think the sweet spot is JUBU 460 Kit with all weight saving you can do. If you have the money I think the JUBU 500 is absolutely perfect!

I loved the Emira in many aspect but 1 main concern when I test drove it. It’s not a fast car. People that tell you it’s fast, haven’t had fast cars. It’s quick yes and it’s plenty for most, which is why Lotus gave it what it did. They are not wrong since people are buying them and loving it. But the cost your paying isn’t for the power and I think we can all agree on this, do we wish we all were given more yes obviously lol!

That being said when I placed my order I knew I would be upgrading the power and I have already gone with the JUBU 440 kit. Absolutely love it has a launch control and raising the rpm to 7,200 was also a need since I felt it cut power sooner than the claimed 6,800 (others have said the same thing so it’s not wrong, some just are more in tune with what’s going on than others) The way I have my car set up now is how the car “power wise” should have come from the factory. So to me I am where I should have been stock, so I do plan on further stages soon probably the end all be all for me is the JUBU 500 with forged internals down the road.

I know these stages will cost money but at the end of the day I will pay just over what a manual GT4 would cost me (new as I would spec before I lost my allocation since they discontinued it)
and I will have more power, better handling (with some more mods) way better looking/special looking car and better sounding.

It cost less to go with JUBU 460 then do all the weight savings. So how I structured my build is 440 JUBU with some weight saving small items exhaust and battery, next is 460 JUBU then all other impactful weight saving mods like wheels and seats etc.
I think with this I will be really happy for awhile bc I would have saved around 130-150 lbs give or take depending what I choose, and ill be at minimum 460 hp as the tune only restricts tq so depending on my specific engine I could be at 475-490 according to JUBU. I would do a dyno at some point to see my numbers and my tq is limited at max 369 lb/ft until I do the 500 kit.

That’s my plan doesn’t have to be yours, make it your own, be honest in what you want out of your car realistically with your budget and needs, make a plan to get there dont stress and enjoy driving the car in the process and don’t wait till the “build” is done bc we all know it’s never done lol. Stay in present, enjoy the journey and have fun!

Does the JUBU raise the redline on the dash display too?

 

[Steve24]

A lot of the mods sound great and I applaud them being available.
I’ll almost certainly do some of them myself, but not because I feel I’ve been ripped off by Lotus.
I’ll do them because I feel it may make the car even better than it already is.

Any claim that Lotus somehow ripped people off because the car doesn’t perform as advertised is BS.

The car does perform as advertised. There’s plenty of evidence of that.
Lotus don’t make traffic light drag cars, and they never claimed the Emira was going to be a car for that.
If that’s a big deal for anyone, you either bought the wrong car or you need to do the mods that have been described above and see if that helps.

But don’t give me this crap about how because some knob in a hot hatch can blow you off at the lights you have been ripped off.

 

[hellasf1]

Does the JUBU raise the redline on the dash display too?

Only raise to 7k there is a system issue do show about that, but you can still go to 7200. Shifting at 7k on the dash thou is still really nice!

 

[Honcho]

Not sure on the figures, but if they are less than advertised Lotus should change as advertised. Saying that, the Emira is not a track car in the form it sells. The suspension is way too soft. Check out the type of spring rates Evora users are using on track and even coming with from factory and you can see a missive difference. Personally for me, the Emira is an amazing looking car with great interior comfort, has a level of exoticness in V6 form, great sound and good road handling. For track i'd be going for something lighter or with a better suspension setup. Power is not an issue for me.

 

[ADC]

Only 163 mph

and only 5th gear

Top speed is in 6th, if vmax is your cup of tea.

 

[ADC]

Feels relevant to the topic at hand, but regardless of swapping ECUs / tuning / raising the limit for more power or not, one thing that I could maybe talk myself into addressing via aftermarket tuning is having a less aggressive limiter... the stock behaviour is dreadful and almost dangerous. That right there essentially "robs" you of some top end, because you can't even give it the full 6800 without it throwing its hands up and hard cutting the fuel, so you tend to shift earlier to give it a wide berth (or at least I do).

That aside, I don't feel particularly aggrieved about the power or power delivery otherwise. And apparently it's ok to have different opinions.

 

[CarrHarris]

I have read through this thread and thought that some research was in order, we have seen times of 4.3 0-60 for the V6 and 3.3-3.5 0-60 for the I4 Emira's.

Let's put that in perspective:

1. 1965 Cobra 427 S/C 0-60 4.3
2. 1992 Cobra 427 S/C 0-60 4.1
3. 2020 Mustang GT 500 0-60 3.4
4. 2012 Ferrari 458 Spider 0-60 3.3
5. 2011 Ferrari 458 Italia 0-60 3.0
6. 2021 Doge Charger 392 0-60 4.2
7. 2021 Dodge SRT Hellcat 0-60 3.5
8. 2023 Cayman GTS 4.0 0-60 3.5

All of the times quoted were done by professional drivers, I have never seen any amateur get close to the factory claimed times on the street, at least with a manual transmission. That is why many magazines are now quoting 5-60 mph runs it is a more realistic metric of what would happen on the street.

I don't think anyone would consider these cars to be slow, yet the Emira in one form or another is the equal or close to all of them. Further, as has been stated above the Emira was not and is not designed to be a stop light hero. If you think the car is slow go to Hethel and drive it with a Lotus coach next to you. Nobody in my class thought it needed more power, all that was needed was more skill of the driver. If I remember correctly putting the car in track mode or turning off the nannies raised the red line, I remember seeing ~137 mph in 4th gear close to or at the redline, that was in a car that had three years on the test track. The Emira is a car for those who put handling and the driving experience at the forefront of what they want out of car.

I am not trying to create an argument only trying to put the 0-60 times in perspective and like everyone else here give my opinion.

Cheers!

 

[Emiro]

There's really no need to get all up in arms over this. It's a car, and like pretty much any car that's stock from the factory, it's a base starting point for performance increases which is typically what modding is all about.

A Lotus has never been about power or straight line acceleration, but this one is reasonably close to be worth (in my opinion) spending a few coins to improve it, which is what I'm doing. I also enjoy doing this.

There's also two types of weight reduction; static weight and rotating weight. The Honda report was only talking about static weight reduction. Reducing rotating weight, especially unsprung rotating weight is by far much more beneficial. The 2 areas where that's doable are wheels and brake rotors. Engine flywheel and/or clutch (if it's a manual trans.) is another area where the benefit is greater than the amount of weight removed. Better oils that reduce friction and lower resistance can also help.

On the scale of benefit to cost, the cheapest way to start reducing weight is to replace the 43 lb factory battery with a 13 lb Antigravity 40ah battery (GRP sells these) which currently is $819. That's an instant 30 lb reduction with no modifications necessary; slides right into the factory mounts.

The prices start to go up from there for mod improvements.

The next best value (from my experience) was the Eventuri, which cost $1,600 but delivered a clean increase of 16 hp and 15 ft lbs of torque to the rear wheels. I know GRP's same-day test of the Eventuri and other intakes didn't produce those kinds of numbers, but I suspect it was because the ECU didn't have enough time to adjust to each of them. I've done multiple dyno runs stretched out over months, and the results are always consistent.

Next I would put lighter wheels as a good mod. @Aerie has some nice offerings that will typically remove a combined weight of about 24 lbs for all 4 wheels. That's unsprung rotating weight (URW). There are several different opinions of how much of a weight reduction benefit that gives, from anywhere to the equivalent of 4x to 10x the amount of static weight. Just to be conservative, even if you go with the lowest of 4x, removing 24 lbs of URW would have the equivalent effect of removing 96 lbs of static weight. That you can feel. A set of forged aluminum wheels from Aerie will be around $3k (providing tariffs don't change that) which includes shipping. They're well-made, with good finishes.

I know a lot of people do 3rd cat deletes, but I didn't do that so I don't have any data to share. According to Jubu, that supposedly frees up about 5 hp to the rear wheels so that may be worthwhile, and it's relatively cheap if you don't mind the extra noise. Many want the noise, but I didn't.

The titanium exhaust is nice, but at $2,500 it's a bit pricey and isn't going to give you the same benefit spending that same amount of money would on a lighter set of wheels. Depends on your budget and what you want to spend. The benefit of the titanium exhaust is a reduction in weight of about 18 lbs (for the Aerie), and when I dynoed it, there was an increase in torque up to about 2800 rpm, which was nice. I feel more torque at the lower rpms is what the Emira needs the most.

Now you start getting into the really expensive mods. Seats are going to be above $6k, but you do get about a 66 lb reduction in weight. According to @kitkat it does get much louder inside the car; the factory seats apparently absorb a lot of noise. This mod is debatable for a street build, but probably worthwhile for a track focused build.

Next would be either expensive wheels even lighter than what Aerie provides, but now you're up around $10k. What I've chosen to do is go with @Warren-RB RacingBrake's carbon ceramic rotor kit. Also not cheap at $11,600, but it's a reduction of about 23 lbs of URW which according to the 4x formula, will have the effect of removing 92 lbs of static weight. In addition, there should be a drastic reduction in brake dust issues. So between the lighter Aerie wheels and the RB CCB rotors, that's an equivalent weight reduction of 188 lbs, not to mention the actual static weight reduction.

So do you 'have' to do any of this? No, of course not. The Emira as-is is a really nice sports car. If you want a bit more performance, I would say based on my experience, the Eventuri will do the most for you, even before the lighter battery. After that, it's up to you, your budget, and how much you want to do and spend.

There's really no need to get all up in arms over this. It's a car, and like pretty much any car that's stock from the factory, it's a base starting point for performance increases which is typically what modding is all about.

A Lotus has never been about power or straight line acceleration, but this one is reasonably close to be worth (in my opinion) spending a few coins to improve it, which is what I'm doing. I also enjoy doing this.

There's also two types of weight reduction; static weight and rotating weight. The Honda report was only talking about static weight reduction. Reducing rotating weight, especially unsprung rotating weight is by far much more beneficial. The 2 areas where that's doable are wheels and brake rotors. Engine flywheel and/or clutch (if it's a manual trans.) is another area where the benefit is greater than the amount of weight removed. Better oils that reduce friction and lower resistance can also help.

On the scale of benefit to cost, the cheapest way to start reducing weight is to replace the 43 lb factory battery with a 13 lb Antigravity 40ah battery (GRP sells these) which currently is $819. That's an instant 30 lb reduction with no modifications necessary; slides right into the factory mounts.

The prices start to go up from there for mod improvements.

The next best value (from my experience) was the Eventuri, which cost $1,600 but delivered a clean increase of 16 hp and 15 ft lbs of torque to the rear wheels. I know GRP's same-day test of the Eventuri and other intakes didn't produce those kinds of numbers, but I suspect it was because the ECU didn't have enough time to adjust to each of them. I've done multiple dyno runs stretched out over months, and the results are always consistent.

Next I would put lighter wheels as a good mod. @Aerie has some nice offerings that will typically remove a combined weight of about 24 lbs for all 4 wheels. That's unsprung rotating weight (URW). There are several different opinions of how much of a weight reduction benefit that gives, from anywhere to the equivalent of 4x to 10x the amount of static weight. Just to be conservative, even if you go with the lowest of 4x, removing 24 lbs of URW would have the equivalent effect of removing 96 lbs of static weight. That you can feel. A set of forged aluminum wheels from Aerie will be around $3k (providing tariffs don't change that) which includes shipping. They're well-made, with good finishes.

I know a lot of people do 3rd cat deletes, but I didn't do that so I don't have any data to share. According to Jubu, that supposedly frees up about 5 hp to the rear wheels so that may be worthwhile, and it's relatively cheap if you don't mind the extra noise. Many want the noise, but I didn't.

The titanium exhaust is nice, but at $2,500 it's a bit pricey and isn't going to give you the same benefit spending that same amount of money would on a lighter set of wheels. Depends on your budget and what you want to spend. The benefit of the titanium exhaust is a reduction in weight of about 18 lbs (for the Aerie), and when I dynoed it, there was an increase in torque up to about 2800 rpm, which was nice. I feel more torque at the lower rpms is what the Emira needs the most.

Now you start getting into the really expensive mods. Seats are going to be above $6k, but you do get about a 66 lb reduction in weight. According to @kitkat it does get much louder inside the car; the factory seats apparently absorb a lot of noise. This mod is debatable for a street build, but probably worthwhile for a track focused build.

Next would be either expensive wheels even lighter than what Aerie provides, but now you're up around $10k. What I've chosen to do is go with @Warren-RB RacingBrake's carbon ceramic rotor kit. Also not cheap at $11,600, but it's a reduction of about 23 lbs of URW which according to the 4x formula, will have the effect of removing 92 lbs of static weight. In addition, there should be a drastic reduction in brake dust issues. So between the lighter Aerie wheels and the RB CCB rotors, that's an equivalent weight reduction of 188 lbs, not to mention the actual static weight reduction.

So do you 'have' to do any of this? No, of course not. The Emira as-is is a really nice sports car. If you want a bit more performance, I would say based on my experience, the Eventuri will do the most for you, even before the lighter battery. After that, it's up to you, your budget, and how much you want to do and spend.

This is very useful. I'd be a shame to get this information lost in the middle of this post... Ideally it should have its own post and perhaps made as a table that people can keep adding with new modifications / weight saved / hp gains

 

[Tomwa]

I just don't think the rotational mass myth is true.

For one thing, across the internet its never consistent. Sometimes its 4x, other times 5x or more.

Second, rotational mass would affect how quickly the revs can climb in a car, making the engine feel more responsive, but the engine won't have a more effective torque or hp delivery. That's not how it works with a light weight flywheel, it just means that the engine revs more freely. If your HP delivery is more peaky at the top of the RPM range, maybe it means you get there faster, but you also fall out of it faster.

Based on this testing from Car and Driver. a 14lb per corner weight difference (56lbs total weight drop) only accounted for a 0.3 second improvement in 0-60, and a 1 second improvement to 100. But.... the car is also nearly 60lbs lighter, and the tire & wheel package is 2% taller between the 19inch and 15inch. So, how much of that improvement is based just on weight and not "rotational weight" combined with a slower accel from 2% taller tires?


Unfortunately this isn't a full test, where it would include (in my mind) a mechanism where you could isolate the weight to just rotational weight gains. Which would be to either remove weight from the car for the heavier wheel package or add weight back for the lighter ones. Regardless, it proves there is VERY limited gain to be found, especially as the Emira several seconds faster to 60mph, which makes each 1/10th of a second harder to achieve.

 

[Eagle7]

I just don't think the rotational mass myth is true.

For one thing, across the internet its never consistent. Sometimes its 4x, other times 5x or more.

Second, rotational mass would affect how quickly the revs can climb in a car, making the engine feel more responsive, but the engine won't have a more effective torque or hp delivery. That's not how it works with a light weight flywheel, it just means that the engine revs more freely. If your HP delivery is more peaky at the top of the RPM range, maybe it means you get there faster, but you also fall out of it faster.

Based on this testing from Car and Driver. a 14lb per corner weight difference (56lbs total weight drop) only accounted for a 0.3 second improvement in 0-60, and a 1 second improvement to 100. But.... the car is also nearly 60lbs lighter, and the tire & wheel package is 2% taller between the 19inch and 15inch. So, how much of that improvement is based just on weight and not "rotational weight" combined with a slower accel from 2% taller tires?


Unfortunately this isn't a full test, where it would include (in my mind) a mechanism where you could isolate the weight to just rotational weight gains. Which would be to either remove weight from the car for the heavier wheel package or add weight back for the lighter ones. Regardless, it proves there is VERY limited gain to be found, especially as the Emira several seconds faster to 60mph, which makes each 1/10th of a second harder to achieve.

The problem with this test is the wheel sizes and tire widths keep changing, which isn't really representative of reducing URW for the same size wheels and tires. By the time they get down to the 15" wheels, it's on the same car with the same body mass weight, but they've lost 2.5" of tire width, the lateral g's have gone down, and the braking distance has increased by 4 feet. If they had done a test with the original 19x8.5" size wheels where they had switched to a set the same size but 14 lbs lighter, that would be a much more realistic representation of the actual effect.

I remember Al Oppenheiser who was the Chief Engineer at GM for the Camaro, said they had found in testing and development, that it took a reduction of I believe it was 225 lbs of static weight to improve the 1/4 time by .5 seconds or something like that, so the differences in straight line results aren't massive.

Where I've always noticed it was the feeling of how much easier it is to get the car going in the first place, and initial acceleration response. It takes torque to get mass moving, and horsepower to push it through resistance to movement. On the street, if you reduce the amount of mass the car has to twist to get moving, which is where your torque is going, you'll get moving faster quicker.

The overall effect of moving faster quicker can be achieved either through static weight reduction, or rotating weight reduction. Removing hundreds of pounds of static weight in a street car is going to be destructive to the original streetable value of the car. Typically that means it's going to be louder/noisier inside, which affects the comfort level of being in the car for any length of time. If you're young and that sort of thing is exciting and gets your adrenaline flowing, cool. If you're older and would rather have more of the comfort and less noise inside the car, then reducing URW will give you the same benefits of just removing mass weight, without the loss of comfortability inside the car.

Either way costs, with removing mass weight usually being done by replacing heavier factory components with carbon fiber, or forged metals like aluminum or magnesium. That stuff removes weight, but it's not cheap.

One of the things straight line tests don't show is how the car performs in the corners. You can tell the difference immediately by how quickly (or not) a car wants to turn and perform while cornering. If the suspension has less mass to manage, it responds quicker, and you can feel it which is often described as the car feeling lighter on its feet.

The easiest way for people to understand performance is with straight line acceleration, which is also the easiest thing to measure and record. Anybody can experience and do that. It's much harder to document the feel and effect of cornering, but that's where you'll really appreciate the reduction in URW, especially on a car with a first class chassis like a Lotus.

 

[hellasf1]

Feels relevant to the topic at hand, but regardless of swapping ECUs / tuning / raising the limit for more power or not, one thing that I could maybe talk myself into addressing via aftermarket tuning is having a less aggressive limiter... the stock behaviour is dreadful and almost dangerous. That right there essentially "robs" you of some top end, because you can't even give it the full 6800 without it throwing its hands up and hard cutting the fuel, so you tend to shift earlier to give it a wide berth (or at least I do).

That aside, I don't feel particularly aggrieved about the power or power delivery otherwise. And apparently it's ok to have different opinions.

That’s another reason that drove me to aftermarket tuning. It happened to me on the test drive and I wasn’t at redline I saw it. So I thought it’s a demo car bla bla bla. Got mine and when I finally let it rip happen to me and it is dangerous especially if your going fast on a long bend it really unsettles the car being mid engine.

 

[Eagle7]

That’s another reason that drove me to aftermarket tuning. It happened to me on the test drive and I wasn’t at redline I saw it. So I thought it’s a demo car bla bla bla. Got mine and when I finally let it rip happen to me and it is dangerous especially if your going fast on a long bend it really unsettles the car being mid engine.

Yeah I can agree with this. The first time I hit the limiter I actually thought I'd hit something, it was so violent and sudden. This is something Lotus should definitely fix by making it a softer reduction.

 

[tvs_1320]

I just don't think the rotational mass myth is true.

It's not. You can do the math and get real values. For my S5 assuming 5 lbs saved at the most beneficial point on the 19" wheels, it was equiv to 7.5 lbs of non-rotational weight. That was for a 2nd gear pull. First gear with higher rotational acceleration would be larger, third would be less, etc. Quoting a 1.5 factor (or lower) doesn't sell products.

Don't get me wrong. Reducing weight has advantages. Reducing rotational weight is better than non rotational, and removing unsprung weight will have benefits on handling. Just have reasonable expectations.

 

[CarGuy11]

Anyone know how much lighter the forged wheels are compared to standard cast wheels on 2025s?

 

[Eagle7]

Anyone know how much lighter the forged wheels are compared to standard cast wheels on 2025s?

I can only speak for the @Aerie wheels since those are the ones I bought, but they were about 24 lbs lighter for all 4 wheels. The factory front wheels weigh 25.64 lbs each, and the factory rear wheels weigh 29.54 lbs each.