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It wouldn't come close to fitting in the T.50. not to mention I think GM made the decision to have camshaft mounted finger followers which are debatable on if that will truly be no adjustment for lifetime of the engine, along with the belt and pulleys vs Cosworth gear driven
GM is ambiguous in this context :)
 

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An interesting engine debate!

Just to touch on the torque vs power point - which I don't think people sufficiently understand:

The first thing you need to realize (and surprisingly few people realize it even though it's fairly obvious) is that cars will have more torque in lower gears than in higher gears. The reason car acceleration gets slower as you go up with speed isn't primarily because of air resistance, but because you are trading torque for the ability to reach higher speeds. The T.50, for example, puts down roughly only 1/4th the torque in 6th gear that it does in 1st gear (and this is almost the same for all cars).

Next thing you need to know is that Power = Torque x RPM.

Now that we know that, let's imagine two engines that both make the same power. One engine will be like the T.50's engine, rev to 12k RPM and make 470Nm of torque. The other engine will be turbocharged and rev to 6k. Since it needs to make the same power with only half the revs, it means it will have twice the torque: 940Nm.

So, will this monster torque have any effect on the performance? None whatsoever. Why is that? Well, let's look at the gearing. For the sake of simplicity, let's say the 1st gear ratio is 3:1 and the final drive is 4:1, for the final torque multiplication of 12:1. Let's also say that taking wheel diameter into account, this allows for 60mph top speed in 1st gear.

The way this works out for the 12k RPM engine is that when it's at 12k RPM, the wheels rotate at 1k RPM. It also means that the torque at the wheels is 12x! That would be 5640Nm in 1st gear.

If we use the same gearing for the 6k RPM engine, what you'll find is while the torque is still multiplied 12x and it makes 11280Nm, when the engine reaches 6k RPM, the wheels rotate only at 500RPM - and so it can only reach 30mph! So in this case what you need to do is change the final drive ratio from 4:1 to 2:1. That way you can reach the same speed, but at the same time it halves the torque.

So, predictably, the final torque at the wheels is identical for both engines! It doesn't really matter whether the engine makes "paltry" 467Nm of torque, or 1000Nm of torque, or 3000Nm of torque because it's an industrial diesel. Power is what matters. Saying that one car will be faster because it has more torque makes exactly as much sense as saying that one car will be faster because it can rev higher!

---

HOWEVER... A completely different discussion is about how the torque curve looks like and what effect that has on acceleration (and usability). This is looking at what percentage of the peak torque you can get at any given engine speed - and because we are looking at percentages, it makes absolutely no difference what the peak value is.

The general perception is that engines that rev higher will have a torque curve that's very weak at low revs and will only really get going at higher revs. While there would probably be a correlation, this is not necessarily true! One example, the screaming V8 in the 458 Speciale that revs to 9k RPM has higher low down torque than the supercharged push-rod V8 in the C7 Z06 Corvette!

How does the T.50's V12 stack up? Well, let's set up a little test. What do you need low down torque for? Probably for something like driving down a highway at 70mph in 6th gear and wanting to accelerate as fast as possible without needing to shift down, right? Ok, let's look at that.

In the T.50, in 6th gear doing 70mph, you'll be at 3487RPM. Now, we don't have a full torque curve yet for the T.50, so here comes a bit of guesswork, but we know that it makes 71% of torque at 2500RPM. That's actually the same as the 991.2 GT3RS, so let's use that torque curve for now. Following that, at 3500RPM the engine will be producing about 78% of its peak torque.

In the 458 Speciale, in 7th at 70mph you'll be at 2922RPM, making 79% of peak torque. In the C7 Z06 Corvette, you'll be at 1514RPM, making 73% of peak torque.

So there you go, the T.50 actually makes higher percentage of peak torque in that situation than the supercharged Corvette, which makes 881Nm (and almost similar power at 659PS). And, even if it didn't, there is still the fact that the T.50 is 550kg lighter than the Corvette, so even if the Corvette was at 100% of peak torque, the T.50 would still leave it in the dust, even with both cars in 6th gear at low engine speed. I wouldn't really worry about T.50's ability to accelerate, no matter the circumstance. It's gonna be frighteningly fast and powerful enough to be tire limited in 1st, 2nd and maybe even 3rd gear if the conditions are not perfect!

---

Lastly, and sorry for the long post, about the T.50's engine compared to the C8 Z06 one. Objectively, there is really no comparison. The T.50's engine is lighter (178kg vs 212kg), smaller, makes more power per kg (3.72 vs 3.21), more power per liter (166 vs 124), more torque per liter (116.8 vs 113.5) and revs much higher. The revs, as you might have learned, are not there just for show or for noise, but more revs mean more power! That's how the power per kg and per liter gets so high - and why F1 engines rev as high as possible!

The T.50's engine is also much more advanced. It uses Metal Matrix Composite pistons - which is a first on a road car. It has a VVT system that's able to work at 12k RPM (that was one of the big challenges and why you haven't seen any engines reach 12k up until now) and loads of other trick stuff to make the high redline possible. It has plasma sprayed iron coated cylinder walls, CNC machined crankshaft, only 85mm crank height (115mm on the SF90, for example), triple vacuum remelted springs, etc. It also has more torque per liter which means they are able to get more work out of the combustion.

The Corvette engine is great and I am very happy that they decided to make it, but technically it doesn't seem to be any better than the Ferrari 458 engine and actually it's worse in some aspects. Maybe it's not completely fair to compare it to an engine from more than 10 years ago because of changing emission regs that make creating power more difficult, but it probably wouldn't be completely unfair to say that the Corvette engine is where Ferrari was 10 years ago. The Cosworth engine is where NA engines could have been if the development didn't stop and go towards turbos. Now let's just hope it's reliable :p.
 

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An interesting engine debate!

Just to touch on the torque vs power point - which I don't think people sufficiently understand:

The first thing you need to realize (and surprisingly few people realize it even though it's fairly obvious) is that cars will have more torque in lower gears than in higher gears. The reason car acceleration gets slower as you go up with speed isn't primarily because of air resistance, but because you are trading torque for the ability to reach higher speeds. The T.50, for example, puts down roughly only 1/4th the torque in 6th gear that it does in 1st gear (and this is almost the same for all cars).

Next thing you need to know is that Power = Torque x RPM.

Now that we know that, let's imagine two engines that both make the same power. One engine will be like the T.50's engine, rev to 12k RPM and make 470Nm of torque. The other engine will be turbocharged and rev to 6k. Since it needs to make the same power with only half the revs, it means it will have twice the torque: 940Nm.

So, will this monster torque have any effect on the performance? None whatsoever. Why is that? Well, let's look at the gearing. For the sake of simplicity, let's say the 1st gear ratio is 3:1 and the final drive is 4:1, for the final torque multiplication of 12:1. Let's also say that taking wheel diameter into account, this allows for 60mph top speed in 1st gear.

The way this works out for the 12k RPM engine is that when it's at 12k RPM, the wheels rotate at 1k RPM. It also means that the torque at the wheels is 12x! That would be 5640Nm in 1st gear.

If we use the same gearing for the 6k RPM engine, what you'll find is while the torque is still multiplied 12x and it makes 11280Nm, when the engine reaches 6k RPM, the wheels rotate only at 500RPM - and so it can only reach 30mph! So in this case what you need to do is change the final drive ratio from 4:1 to 2:1. That way you can reach the same speed, but at the same time it halves the torque.

So, predictably, the final torque at the wheels is identical for both engines! It doesn't really matter whether the engine makes "paltry" 467Nm of torque, or 1000Nm of torque, or 3000Nm of torque because it's an industrial diesel. Power is what matters. Saying that one car will be faster because it has more torque makes exactly as much sense as saying that one car will be faster because it can rev higher!

---

HOWEVER... A completely different discussion is about how the torque curve looks like and what effect that has on acceleration (and usability). This is looking at what percentage of the peak torque you can get at any given engine speed - and because we are looking at percentages, it makes absolutely no difference what the peak value is.

The general perception is that engines that rev higher will have a torque curve that's very weak at low revs and will only really get going at higher revs. While there would probably be a correlation, this is not necessarily true! One example, the screaming V8 in the 458 Speciale that revs to 9k RPM has higher low down torque than the supercharged push-rod V8 in the C7 Z06 Corvette!

How does the T.50's V12 stack up? Well, let's set up a little test. What do you need low down torque for? Probably for something like driving down a highway at 70mph in 6th gear and wanting to accelerate as fast as possible without needing to shift down, right? Ok, let's look at that.

In the T.50, in 6th gear doing 70mph, you'll be at 3487RPM. Now, we don't have a full torque curve yet for the T.50, so here comes a bit of guesswork, but we know that it makes 71% of torque at 2500RPM. That's actually the same as the 991.2 GT3RS, so let's use that torque curve for now. Following that, at 3500RPM the engine will be producing about 78% of its peak torque.

In the 458 Speciale, in 7th at 70mph you'll be at 2922RPM, making 79% of peak torque. In the C7 Z06 Corvette, you'll be at 1514RPM, making 73% of peak torque.

So there you go, the T.50 actually makes higher percentage of peak torque in that situation than the supercharged Corvette, which makes 881Nm (and almost similar power at 659PS). And, even if it didn't, there is still the fact that the T.50 is 550kg lighter than the Corvette, so even if the Corvette was at 100% of peak torque, the T.50 would still leave it in the dust, even with both cars in 6th gear at low engine speed. I wouldn't really worry about T.50's ability to accelerate, no matter the circumstance. It's gonna be frighteningly fast and powerful enough to be tire limited in 1st, 2nd and maybe even 3rd gear if the conditions are not perfect!

---

Lastly, and sorry for the long post, about the T.50's engine compared to the C8 Z06 one. Objectively, there is really no comparison. The T.50's engine is lighter (178kg vs 212kg), smaller, makes more power per kg (3.72 vs 3.21), more power per liter (166 vs 124), more torque per liter (116.8 vs 113.5) and revs much higher. The revs, as you might have learned, are not there just for show or for noise, but more revs mean more power! That's how the power per kg and per liter gets so high - and why F1 engines rev as high as possible!

The T.50's engine is also much more advanced. It uses Metal Matrix Composite pistons - which is a first on a road car. It has a VVT system that's able to work at 12k RPM (that was one of the big challenges and why you haven't seen any engines reach 12k up until now) and loads of other trick stuff to make the high redline possible. It has plasma sprayed iron coated cylinder walls, CNC machined crankshaft, only 85mm crank height (115mm on the SF90, for example), triple vacuum remelted springs, etc. It also has more torque per liter which means they are able to get more work out of the combustion.

The Corvette engine is great and I am very happy that they decided to make it, but technically it doesn't seem to be any better than the Ferrari 458 engine and actually it's worse in some aspects. Maybe it's not completely fair to compare it to an engine from more than 10 years ago because of changing emission regs that make creating power more difficult, but it probably wouldn't be completely unfair to say that the Corvette engine is where Ferrari was 10 years ago. The Cosworth engine is where NA engines could have been if the development didn't stop and go towards turbos. Now let's just hope it's reliable :p.
Tremendous.
 

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An interesting engine debate!

Just to touch on the torque vs power point - which I don't think people sufficiently understand:

The first thing you need to realize (and surprisingly few people realize it even though it's fairly obvious) is that cars will have more torque in lower gears than in higher gears. The reason car acceleration gets slower as you go up with speed isn't primarily because of air resistance, but because you are trading torque for the ability to reach higher speeds. The T.50, for example, puts down roughly only 1/4th the torque in 6th gear that it does in 1st gear (and this is almost the same for all cars).

Next thing you need to know is that Power = Torque x RPM.

Now that we know that, let's imagine two engines that both make the same power. One engine will be like the T.50's engine, rev to 12k RPM and make 470Nm of torque. The other engine will be turbocharged and rev to 6k. Since it needs to make the same power with only half the revs, it means it will have twice the torque: 940Nm.

So, will this monster torque have any effect on the performance? None whatsoever. Why is that? Well, let's look at the gearing. For the sake of simplicity, let's say the 1st gear ratio is 3:1 and the final drive is 4:1, for the final torque multiplication of 12:1. Let's also say that taking wheel diameter into account, this allows for 60mph top speed in 1st gear.

The way this works out for the 12k RPM engine is that when it's at 12k RPM, the wheels rotate at 1k RPM. It also means that the torque at the wheels is 12x! That would be 5640Nm in 1st gear.

If we use the same gearing for the 6k RPM engine, what you'll find is while the torque is still multiplied 12x and it makes 11280Nm, when the engine reaches 6k RPM, the wheels rotate only at 500RPM - and so it can only reach 30mph! So in this case what you need to do is change the final drive ratio from 4:1 to 2:1. That way you can reach the same speed, but at the same time it halves the torque.

So, predictably, the final torque at the wheels is identical for both engines! It doesn't really matter whether the engine makes "paltry" 467Nm of torque, or 1000Nm of torque, or 3000Nm of torque because it's an industrial diesel. Power is what matters. Saying that one car will be faster because it has more torque makes exactly as much sense as saying that one car will be faster because it can rev higher!

---

HOWEVER... A completely different discussion is about how the torque curve looks like and what effect that has on acceleration (and usability). This is looking at what percentage of the peak torque you can get at any given engine speed - and because we are looking at percentages, it makes absolutely no difference what the peak value is.

The general perception is that engines that rev higher will have a torque curve that's very weak at low revs and will only really get going at higher revs. While there would probably be a correlation, this is not necessarily true! One example, the screaming V8 in the 458 Speciale that revs to 9k RPM has higher low down torque than the supercharged push-rod V8 in the C7 Z06 Corvette!

How does the T.50's V12 stack up? Well, let's set up a little test. What do you need low down torque for? Probably for something like driving down a highway at 70mph in 6th gear and wanting to accelerate as fast as possible without needing to shift down, right? Ok, let's look at that.

In the T.50, in 6th gear doing 70mph, you'll be at 3487RPM. Now, we don't have a full torque curve yet for the T.50, so here comes a bit of guesswork, but we know that it makes 71% of torque at 2500RPM. That's actually the same as the 991.2 GT3RS, so let's use that torque curve for now. Following that, at 3500RPM the engine will be producing about 78% of its peak torque.

In the 458 Speciale, in 7th at 70mph you'll be at 2922RPM, making 79% of peak torque. In the C7 Z06 Corvette, you'll be at 1514RPM, making 73% of peak torque.

So there you go, the T.50 actually makes higher percentage of peak torque in that situation than the supercharged Corvette, which makes 881Nm (and almost similar power at 659PS). And, even if it didn't, there is still the fact that the T.50 is 550kg lighter than the Corvette, so even if the Corvette was at 100% of peak torque, the T.50 would still leave it in the dust, even with both cars in 6th gear at low engine speed. I wouldn't really worry about T.50's ability to accelerate, no matter the circumstance. It's gonna be frighteningly fast and powerful enough to be tire limited in 1st, 2nd and maybe even 3rd gear if the conditions are not perfect!

---

Lastly, and sorry for the long post, about the T.50's engine compared to the C8 Z06 one. Objectively, there is really no comparison. The T.50's engine is lighter (178kg vs 212kg), smaller, makes more power per kg (3.72 vs 3.21), more power per liter (166 vs 124), more torque per liter (116.8 vs 113.5) and revs much higher. The revs, as you might have learned, are not there just for show or for noise, but more revs mean more power! That's how the power per kg and per liter gets so high - and why F1 engines rev as high as possible!

The T.50's engine is also much more advanced. It uses Metal Matrix Composite pistons - which is a first on a road car. It has a VVT system that's able to work at 12k RPM (that was one of the big challenges and why you haven't seen any engines reach 12k up until now) and loads of other trick stuff to make the high redline possible. It has plasma sprayed iron coated cylinder walls, CNC machined crankshaft, only 85mm crank height (115mm on the SF90, for example), triple vacuum remelted springs, etc. It also has more torque per liter which means they are able to get more work out of the combustion.

The Corvette engine is great and I am very happy that they decided to make it, but technically it doesn't seem to be any better than the Ferrari 458 engine and actually it's worse in some aspects. Maybe it's not completely fair to compare it to an engine from more than 10 years ago because of changing emission regs that make creating power more difficult, but it probably wouldn't be completely unfair to say that the Corvette engine is where Ferrari was 10 years ago. The Cosworth engine is where NA engines could have been if the development didn't stop and go towards turbos. Now let's just hope it's reliable :p.
Torque is not the simplest way to understand this. Most people simply don't understand it.

Acceleration = nett engine power / road speed

Done.
 

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Just noticed that on Gordon Murray Automotive's site that they finally quote a downforce for the T50. They are stating 322 kg downforce (which I assume is at top speed, like the value for the T50.S). That's actually not bad at all for a car this clean.

That translates to about 153 kg downforce at 155 mph to compare to some other manufacturers. This is about comparable to what Ferrari claimed for the 458, although I trust GMA a bit more than Ferrari in this respect.
 

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Just noticed that on Gordon Murray Automotive's site that they finally quote a downforce for the T50. They are stating 322 kg downforce (which I assume is at top speed, like the value for the T50.S). That's actually not bad at all for a car this clean.

That translates to about 153 kg downforce at 155 mph to compare to some other manufacturers. This is about comparable to what Ferrari claimed for the 458, although I trust GMA a bit more than Ferrari in this respect.
Actually they had that info on there since the unveiling of the T.50S early last year ;). In any case, I think the downforce at 250km/h is gonna be even higher. 322kg is, as you say, at top speed, but very likely they start bleeding the downforce way before that - that's the whole point of the fan, after all! The 322kg could already be reached at 250km/h. We don't really have a definitive figure but from the comments GM made about the T.50S - which he said makes 3x the downforce of the T.50 - it could be deduced that the T.50 creates about 275kg of downforce at 250km/h (155mph). That's about the same as the 991.2 GT2RS (289kg). The 720S is 242kg and the 765LT is 302kg. Keep in mind, though, that claimed downforce figures are one of the more unreliable stats that manufacturers list. These numbers could be true, or they could also be completely, wildly different :).
 

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Actually they had that info on there since the unveiling of the T.50S early last year ;). In any case, I think the downforce at 250km/h is gonna be even higher. 322kg is, as you say, at top speed, but very likely they start bleeding the downforce way before that - that's the whole point of the fan, after all! The 322kg could already be reached at 250km/h. We don't really have a definitive figure but from the comments GM made about the T.50S - which he said makes 3x the downforce of the T.50 - it could be deduced that the T.50 creates about 275kg of downforce at 250km/h (155mph). That's about the same as the 991.2 GT2RS.(289kg). The 720S is 242kg and the 765LT is 302kg. Keep in mind, though, that claimed downforce figures are one of the more unreliable stats that manufacturers claim. These numbers could be true, or they could also be completely, wildly different :).
I probably even commented on it at that time and already forgot, lol. But yeah, with the active boundary layer control, the downforce curve vs speed could be very different than typical squared relationship
 

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An interesting engine debate!

Just to touch on the torque vs power point - which I don't think people sufficiently understand:

The first thing you need to realize (and surprisingly few people realize it even though it's fairly obvious) is that cars will have more torque in lower gears than in higher gears. The reason car acceleration gets slower as you go up with speed isn't primarily because of air resistance, but because you are trading torque for the ability to reach higher speeds. The T.50, for example, puts down roughly only 1/4th the torque in 6th gear that it does in 1st gear (and this is almost the same for all cars).

Next thing you need to know is that Power = Torque x RPM.

Now that we know that, let's imagine two engines that both make the same power. One engine will be like the T.50's engine, rev to 12k RPM and make 470Nm of torque. The other engine will be turbocharged and rev to 6k. Since it needs to make the same power with only half the revs, it means it will have twice the torque: 940Nm.

So, will this monster torque have any effect on the performance? None whatsoever. Why is that? Well, let's look at the gearing. For the sake of simplicity, let's say the 1st gear ratio is 3:1 and the final drive is 4:1, for the final torque multiplication of 12:1. Let's also say that taking wheel diameter into account, this allows for 60mph top speed in 1st gear.

The way this works out for the 12k RPM engine is that when it's at 12k RPM, the wheels rotate at 1k RPM. It also means that the torque at the wheels is 12x! That would be 5640Nm in 1st gear.

If we use the same gearing for the 6k RPM engine, what you'll find is while the torque is still multiplied 12x and it makes 11280Nm, when the engine reaches 6k RPM, the wheels rotate only at 500RPM - and so it can only reach 30mph! So in this case what you need to do is change the final drive ratio from 4:1 to 2:1. That way you can reach the same speed, but at the same time it halves the torque.

So, predictably, the final torque at the wheels is identical for both engines! It doesn't really matter whether the engine makes "paltry" 467Nm of torque, or 1000Nm of torque, or 3000Nm of torque because it's an industrial diesel. Power is what matters. Saying that one car will be faster because it has more torque makes exactly as much sense as saying that one car will be faster because it can rev higher!

---

HOWEVER... A completely different discussion is about how the torque curve looks like and what effect that has on acceleration (and usability). This is looking at what percentage of the peak torque you can get at any given engine speed - and because we are looking at percentages, it makes absolutely no difference what the peak value is.

The general perception is that engines that rev higher will have a torque curve that's very weak at low revs and will only really get going at higher revs. While there would probably be a correlation, this is not necessarily true! One example, the screaming V8 in the 458 Speciale that revs to 9k RPM has higher low down torque than the supercharged push-rod V8 in the C7 Z06 Corvette!

How does the T.50's V12 stack up? Well, let's set up a little test. What do you need low down torque for? Probably for something like driving down a highway at 70mph in 6th gear and wanting to accelerate as fast as possible without needing to shift down, right? Ok, let's look at that.

In the T.50, in 6th gear doing 70mph, you'll be at 3487RPM. Now, we don't have a full torque curve yet for the T.50, so here comes a bit of guesswork, but we know that it makes 71% of torque at 2500RPM. That's actually the same as the 991.2 GT3RS, so let's use that torque curve for now. Following that, at 3500RPM the engine will be producing about 78% of its peak torque.

In the 458 Speciale, in 7th at 70mph you'll be at 2922RPM, making 79% of peak torque. In the C7 Z06 Corvette, you'll be at 1514RPM, making 73% of peak torque.

So there you go, the T.50 actually makes higher percentage of peak torque in that situation than the supercharged Corvette, which makes 881Nm (and almost similar power at 659PS). And, even if it didn't, there is still the fact that the T.50 is 550kg lighter than the Corvette, so even if the Corvette was at 100% of peak torque, the T.50 would still leave it in the dust, even with both cars in 6th gear at low engine speed. I wouldn't really worry about T.50's ability to accelerate, no matter the circumstance. It's gonna be frighteningly fast and powerful enough to be tire limited in 1st, 2nd and maybe even 3rd gear if the conditions are not perfect!

---

Lastly, and sorry for the long post, about the T.50's engine compared to the C8 Z06 one. Objectively, there is really no comparison. The T.50's engine is lighter (178kg vs 212kg), smaller, makes more power per kg (3.72 vs 3.21), more power per liter (166 vs 124), more torque per liter (116.8 vs 113.5) and revs much higher. The revs, as you might have learned, are not there just for show or for noise, but more revs mean more power! That's how the power per kg and per liter gets so high - and why F1 engines rev as high as possible!

The T.50's engine is also much more advanced. It uses Metal Matrix Composite pistons - which is a first on a road car. It has a VVT system that's able to work at 12k RPM (that was one of the big challenges and why you haven't seen any engines reach 12k up until now) and loads of other trick stuff to make the high redline possible. It has plasma sprayed iron coated cylinder walls, CNC machined crankshaft, only 85mm crank height (115mm on the SF90, for example), triple vacuum remelted springs, etc. It also has more torque per liter which means they are able to get more work out of the combustion.

The Corvette engine is great and I am very happy that they decided to make it, but technically it doesn't seem to be any better than the Ferrari 458 engine and actually it's worse in some aspects. Maybe it's not completely fair to compare it to an engine from more than 10 years ago because of changing emission regs that make creating power more difficult, but it probably wouldn't be completely unfair to say that the Corvette engine is where Ferrari was 10 years ago. The Cosworth engine is where NA engines could have been if the development didn't stop and go towards turbos. Now let's just hope it's reliable :p.
I'm curious, where did you come by the information regarding the inner materials used in the T.50's engine?
 

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Actually they had that info on there since the unveiling of the T.50S early last year ;). In any case, I think the downforce at 250km/h is gonna be even higher. 322kg is, as you say, at top speed, but very likely they start bleeding the downforce way before that - that's the whole point of the fan, after all! The 322kg could already be reached at 250km/h. We don't really have a definitive figure but from the comments GM made about the T.50S - which he said makes 3x the downforce of the T.50 - it could be deduced that the T.50 creates about 275kg of downforce at 250km/h (155mph). That's about the same as the 991.2 GT2RS (289kg). The 720S is 242kg and the 765LT is 302kg. Keep in mind, though, that claimed downforce figures are one of the more unreliable stats that manufacturers list. These numbers could be true, or they could also be completely, wildly different :).
the main advantage of the fan bleeding downforce is that you can have a suspension that is soft an compliant at normal speeds. One of the reasons high downforce cars are rather stiff around town...
 

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the main advantage of the fan bleeding downforce is that you can have a suspension that is soft an compliant at normal speeds. One of the reasons high downforce cars are rather stiff around town...
Indeed. However, the fan is not the only way to tackle the problem. So as there has also been a lot of discussion about how crucial the fan is, let's look into that!

The first thing you can do, is to employ a few suspension tricks. One of them, which the T.50 also takes advantage of, is to use push-rod suspension. Springs normally have a linear spring rate, but what you can do with push-rod suspension - which uses a rocker to transfer the force from the push-rod to the spring - is to design the rocker so that when it rotates as the wheels are going up the leverage (you are basically pressing on a progressively shorter lever to move a progressively longer lever) changes and the spring, in effect, gets harder to compress.

Another thing you can do, is to use a third spring, also called a heave spring. This is very commonly used on race cars as they have a lot more downforce than street cars. The way it works is that the third springs takes part of the load when both wheels are moving up - and that way your normal springs can be less stiff when dealing with bump motions only affecting one wheel. A disadvantage of this setup is that it's heavier and harder to package.

You can also do what the new Ford GT does and have two springs for each wheel. When the car is in its normal ride setting only one spring is engaged, but when the car gets hydraulically lowered, it gets placed on a second spring that now acts in concert with the first spring, resulting in a much stiffer spring rate. That way you can have the car be relatively comfortable when in normal use, but stiff enough to resist any aerodynamic forces when it's lowered on track. Disadvantages, again, are packaging and weight.

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Apart from that you can obviously try to modulate the amount of downforce itself, which is where active aerodynamics come in. The fan, in effect, is doing the same sort of thing you get with active wings and spoilers and flaps and so on. The question is, how does it compare?

Well, that's rather hard to answer. We know that the fan, including ducting and everything weighs 12kg. How much does the active wing on, let's say, the P1 weigh? No clue, but seeing how many beefy hydraulic elements it contains, together with hydraulic pumps required to run it, I'd wager it's probably substantially more. From the weight to effect ratio standpoint the fan is probably better, but we can't say for certain because there is really no data.

One advantage the fan definitely does have, is that the main downforce generating area it's helping to create is very close to the center of gravity of the car. This is something you don't get with a big active rear wing, which is either gonna create an aero imbalance, or you'll need additional active elements at the front, incurring even more weight penalty. That said, this is not strictly a feature of the fan, but of the overall design of the car. On most supercars, the diffuser basically only starts behind the rear wheels and is not really doing much. On the T.50 the diffuser starts right behind the passenger seats. The reason the diffuser on most supercars is so short is twofold: 1. Without a fan they can't really take advantage of a bigger diffuser; and 2. Even if they had a fan, there wouldn't be enough space in the engine bay to fit a big diffuser! This is really where the superior packaging of the T.50 comes into place. If the engine wasn't so small and wasn't custom made just for the project, the chances are you couldn't fit a big diffuser - and if you couldn't fit a big diffuser then it wouldn't be worth it to continue with the fan idea.

It's really the whole design working together that's making the fan make sense, so it's a bit hard to say how it compares to other solutions in general. I would imagine that of all the other things they could have done, be it using a heave spring or some other suspension trickery, or manipulating the aerodynamics with active flaps and wings, on this car, with how it's been designed, the fan probably is the best solution (and not just fancy throwback to the BT46). Would it be the best solution on all cars? Possibly not.

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One other argument was about whether all this downforce is really necessary in what is supposed to be a pure road car. And I sort of agree there. Having lots of downforce on a road car that is not intended for track driving is pretty much pointless. If you look at the T.50 and its 275kg of downforce at 250km/h, if you are going through a corner at much more realistic 100km/h, the downforce is only gonna be 44kg. Even on a 1100kg car (with driver) that's not really gonna be very noticable.

What I can say in defense is that this is still a hypercar, an aspirational thing. If they can achieve a good performance result using a unique concept not before seen on a road car, why not do it? And, the fan does more than just increasing downforce. It can also be run to reduce drag by 12.5% - which is perhaps the more notable function. 12.5% drag reduction is the same as 12.5% power increase with respect to top speed and approaching 12.5% power increase with respect to acceleration as the car gets faster and drag becomes the major force holding the car down. This is something that active wings (or indeed suspension) can't give you because with a wing there is no active influx of air filling the low pressure area behind the car which where a lot of the drag comes from. Only the fan can do that.

That said, for me the fan is still take it or leave it. I don't hate it and it appears to be a legit and even superior engineering solution, but it's still a bit too funky for my taste and as evidenced by the upcoming T.33, it's not really crucial.
 

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thanks for that very thorough explanation, i think i agree with all of it and much more eloquently expressed than i could have ;)
LMP cars do have a 3rd element to counter the combo of low weight and lots of downforce. they are still pretty stiff in low speed though.
the P1 isnt exactly a merc S class around town, and neither was the Speedtail that seemed to have inherited the stiff P1 suspension in order to have the velocity mode (p1 track mode)
the idea of a Fan to create extra downforce on a road car was one reason i hesitated and missed out on the T50. the bleeding off on downforce with the fan if that can then accomodate a more pliant suspension is a positive.
i'm pretty happy having a fanless T33 on order instead.

are you saying that an active wing like the DRS function in the P1 doesnt reduce drag, or indeed a modern F1 car? i thought that was the whole purpose of a DRS system...
 

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thanks for that very thorough explanation, i think i agree with all of it and much more eloquently expressed than i could have ;)
LMP cars do have a 3rd element to counter the combo of low weight and lots of downforce. they are still pretty stiff in low speed though.
the P1 isnt exactly a merc S class around town, and neither was the Speedtail that seemed to have inherited the stiff P1 suspension in order to have the velocity mode (p1 track mode)
the idea of a Fan to create extra downforce on a road car was one reason i hesitated and missed out on the T50. the bleeding off on downforce with the fan if that can then accomodate a more pliant suspension is a positive.
i'm pretty happy having a fanless T33 on order instead.

are you saying that an active wing like the DRS function in the P1 doesnt reduce drag, or indeed a modern F1 car? i thought that was the whole purpose of a DRS system...
You're still stuck with a wing in the airflow, even at minimal angle of attack. So it's a dragger situation than using a fan
 

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thanks for that very thorough explanation, i think i agree with all of it and much more eloquently expressed than i could have ;)
You are welcome!
are you saying that an active wing like the DRS function in the P1 doesnt reduce drag, or indeed a modern F1 car? i thought that was the whole purpose of a DRS system...
Like TougeSpirit says, if the wing is in the airflow, then it's always gonna produce some drag. However, even if it's fully retracted that only gets the drag to a "base level". The fan can fill the low pressure area behind the car with air, therefore reducing the drag beyond a point where you would be with a car with no wings and no fan. That's the difference.
 
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