Toyota GR GT - All The Engineering Details We Know!

Toyota GR GT - All The Engineering Details We Know!

Engineering Explained

0:00 Twinturbo V8, rearw wheelel drive, all aluminum body frame, insane proportions.

0:07 Yes, Toyota, this is what the people want.

0:10 The new GRGT looks cool as heck.

0:13 And while Toyota hasn't revealed too many details about the car,

0:17 I have an engineering degree allegedly,

0:19 and Toyota has released a bunch of pictures,

0:22 so let's see what we can figure out.

0:24 Now, Toyota claims this roadleal race car has

0:26 had an unrelenting focus on three key elements.

0:30 First, a low center of gravity.

0:32 Second, low weight with high rigidity.

0:35 And third, aerodynamic performance.

0:37 So, we'll look over these, but also estimate the 0

0:40 to 60 time and talk through the engine and transaxle details.

0:44 So, let's start with that first key element, a low center of gravity.

0:48 And here's one of the things I think

0:49 people will be most surprised about this vehicle, just how low of a car it is.

0:54 It is in fact over 3 in shorter than a Honda S2000.

0:59 And it's close to 2 in shorter in height than the new Mazda Miata.

1:04 But what is its center of gravity?

1:06 Can we figure this out?

1:07 Well, Toyota released an image with the center of gravity shown on it.

1:11 Though to be fair, we don't know if the CG placement is entirely accurate.

1:16 But we do know Toyota claims the car

1:18 will have a 4555 front rear weight distribution.

1:22 So if we look at the distance from the center

1:24 line of each wheel to the center of gravity,

1:27 we can actually calculate the weight distribution of the vehicle

1:30 in the image which turns out to be 4555 exactly as Toyota states.

1:39 So this leads me to believe the CG placement in this image is in fact accurate.

1:44 It's so and because we know the vehicle's height,

1:47 we can measure the distance from the ground to the CG

1:50 versus from the ground to the top of the vehicle.

1:52 And this gives us a center of gravity height of about 518 mm.

1:58 Now, you'll notice this is actually a higher center

2:00 of gravity than both the GR86 and the GR Supra, which are both taller vehicles.

2:06 So, why might this be a higher center of gravity height?

2:09 Well, I think there are some logical reasons why this could be accurate.

2:12 First of all, starting off with the GR86.

2:14 This, of course, has a boxer engine, right?

2:17 So, a very low, very flat engine.

2:20 The GRGT has a 90° V8.

2:23 So, the CG of this engine is much higher.

2:25 It also has a hot V setup.

2:27 So, you've got the heavy turbos

2:29 and exhaust components mounted high on the engine.

2:32 Now, the Supra has an inline 6,

2:34 which is a high CG engine, and it's a taller vehicle.

2:38 So, what gives?

2:39 Well, I think the big hint sits above the rear tires in this image.

2:43 That is almost certainly the vehicle's high voltage battery

2:47 pack for the integrated electric motor within the rear transaxle.

2:50 Clearly, there wasn't any space to mount this down low.

2:53 So, as it sits, it's well above the vehicle's center of mass height.

2:57 And as a big, heavy battery, that's surely raising the CG.

3:01 That seems to be the clearest reason why

3:04 this may have a higher CG than the Supra, if the CG location shown is accurate.

3:09 But they still have gone through extensive measures

3:11 to keep the CG as low as possible.

3:13 First of all, the entire powertrain is mounted extremely low.

3:17 You can see just how close it is to the front subframe.

3:20 There's a few things that make this possible.

3:22 For the engine, they're using a shorter stroke

3:25 than you might typically see in a Toyota engine.

3:27 So, this lowers the deck height, which brings down the top of the engine.

3:31 It also has a dry sump oil system which have thinner oil pans.

3:35 So that further allows the engine to drop down helping to enable

3:39 the crazy low hood line for the front of the car.

3:42 The car also makes use of lightweight

3:44 materials especially at high points on the vehicle.

3:47 So you can see carbon fiber used for the hood, for the roof,

3:50 and for the rear bulkhead as well as aluminum body panels.

3:53 All right, but something kind of fun.

3:55 If we know the vehicle's center of gravity height,

3:57 we can actually estimate its 0 to 60 time.

4:00 Because the three key variables we need to know in order to estimate

4:04 that 0 to 60 time are the weight distribution of the car,

4:07 which Toyota provides us,

4:08 the center of gravity height, which we have calculated,

4:11 and the tires grip, which there is plenty of data out there on.

4:14 So, we can use these assumptions and calculate that 0 to 60,

4:18 assuming the vehicle is traction limited.

4:20 But this is a super car.

4:22 It's got a lot of power.

4:22 Let's assume for that 0 to 60 it is traction limited.

4:26 So here's our equation to calculate in GS the maximum acceleration you

4:30 could have for a rear wheel drive vehicle with the given variables.

4:33 If we assume our friction coefficient for our tires is 1.3,

4:37 we could accelerate at 95gs with a 0 to 60 of 2.9 seconds.

4:44 Now if we don't have quite that much grip from our tires, let's say 1.2, 2.

4:48 Well, that gives us an acceleration of86 gs and a 0 to 60 of about 3.2 seconds.

4:54 By the way, this is not including any roll out nonsense, right?

4:57 So, the big car magazines would delete about 2 seconds from each of those times.

5:02 And something that's interesting to note is that having that higher

5:05 center of gravity versus like the 86 and the Supra actually improves

5:09 the 0 to 60 time because it means you have more

5:12 weight transfer to that rear tire which is putting down the power.

5:15 So just as an example, if it were to have the same center of gravity height

5:19 as the GR86 and we have that same grip of 1.3,

5:23 well then we are going to get a 0 to 60 time of about 3.0 seconds.

5:28 So a tenth of a second just from a small

5:31 difference in where that center of gravity is.

5:33 So that's kind of neat.

5:35 Now truthfully, my best guess where is the 0 to 60 of this thing going to fall?

5:39 probably in the low to mid3s because it is fairly

5:42 heavy and it doesn't have an extraordinary amount of power.

5:46 So I think realistically we're looking at low to mid-3s.

5:49 Now there will likely be higher performance

5:51 versions of this released over time, right?

5:53 So I wouldn't be surprised to see that happen and if

5:56 so have that 0 to 60 time dip into the high twos.

5:59 Regardless, it's not going to have the crazy 0

6:02 to 60 times of something like the Corvette ZR1.

6:05 Even though the GRGT has an excellent weight distribution for a rearwheel drive

6:10 vehicle because when the engine goes behind the driver like in the ZR1,

6:14 it just enables so much more grip for a rear wheel drive launch.

6:18 And as always, it often comes down to the tires

6:20 as they make a huge difference in what

6:22 the potential performance numbers will be as I've personally

6:26 experienced on my own GR the rad little GR Corolla.

6:29 Of course, not all cars are performance cars.

6:32 Sometimes practicality is the top priority.

6:35 And with practical cars, the tire selection should match the job.

6:38 In this portion of the video, sponsored by Continental,

6:41 I'm going to be talking about their Cross Contact LX25 tire,

6:44 which I've ran on my Maverick for 2 years

6:47 as my summer tires versus their True Contact Tour 54 tire.

6:51 Both of these tires are allseason touring tires.

6:54 What does that mean?

6:55 Well, what's prioritized in the design of these tires is that they're quiet,

6:59 comfortable, and longlasting with deep treads.

7:03 In fact, these are among Continental's longest lasting tires they

7:06 sell today with up to 70,000 and 80,000 mi warranties, respectively.

7:11 They're both EV compatible, offer great wet grip, have tread indicators,

7:16 so you know when the tire is still good for dry,

7:18 wet, and snow, as well as alignment indicators.

7:21 While both of these touring tires are similar,

7:23 the Tour 54 is geared more towards sedans and crossovers,

7:26 while the LX25 is designed for crossovers and SUVs.

7:30 I only have about 8,000 miles on my truck,

7:34 but the vast majority of those miles have been on these tires,

7:36 and they've been great.

7:38 Now, Toyota's second key element is that the vehicle

7:40 would have low weight and high rigidity.

7:42 But I wouldn't necessarily say this is a lightweight vehicle.

7:45 Toyota claims the weight will be 1750 kg or lower.

7:50 And so, if you look at a competitive set,

7:53 this really isn't that impressive of a number.

7:55 So, this is probably the biggest downside with this vehicle is the weight.

7:59 Looking at the Lexus LFA, of course,

8:01 this was not a hybrid vehicle, so it has that advantage,

8:03 but it did have a larger engine,

8:05 and that vehicle was about 600 lb lighter than the Toyota GRGT.

8:11 If you look at the McLaren 720S, significantly lighter vehicle,

8:15 though, you know, same size engine, twin turbo V8,

8:18 4 L, doesn't have a hybrid system, probably more expensive,

8:22 so perhaps not the best comparison, but here's one.

8:24 Porsche Turbo S.

8:26 This is a vehicle that weighs very similarly, 25 kg less than the GRGT,

8:31 though it has more power,

8:33 it has a powerful hybrid system, and it has all-wheel drive.

8:38 So, all of that and still coming in under

8:40 the weight of Toyota's claim for the GRGT.

8:43 Aston Martin Vantage S,

8:45 probably the closest comparison we could get in terms of weight and performance.

8:49 very similar in power, a little bit more power for the Vantage S and just

8:53 slightly lighter using that same style 4 L twin turbo V8,

8:58 though it does not use a hybrid system, but you know, Aston Martin, right?

9:01 It's got a luxury element to it.

9:03 So, that is always carrying less about weight than,

9:06 you know, cars that are going for allout performance.

9:08 So, GRGT weighing similarly to the Vantage S,

9:12 I feel like is kind of showing, hey, this isn't that light of a vehicle.

9:15 Now, one example out there, the AMG GT63 SP QRS TUV,

9:24 uh, also has a 4 L twin turbo V8.

9:27 Way heavier than the GRGT, but way more power, way more torque.

9:31 It does have a powerful hybrid system,

9:34 and it's also all-wheel drive versus rear wheel drive like the GRGT.

9:38 So realistically, the thing is kind of heavy,

9:40 but that's not to say that Toyota hasn't

9:42 gone to lengths to remove weight from this car.

9:45 Toyota says this is the first time they've used an all aluminum body frame.

9:49 Of course, we mentioned the carbon fiber used with the body panels.

9:53 They're also using Brembo carbon ceramic brakes.

9:55 They've used carbon fiber for the torque

9:57 tube going through the transmission tunnel.

9:59 And leading into Toyota's third key element,

10:02 there are no active aerodynamic elements.

10:04 Everything is passive which helps with weight and removes complexity.

10:08 Now speaking of aerodynamics,

10:10 Toyota says that it took an aerodynamics first approach with this vehicle

10:14 and aerodynamic performance is the third key element for this car.

10:18 Though it seems this is likely referring to aerodynamic efficiency

10:22 as it certainly doesn't look at least like a high downforce car.

10:26 But they are targeting low drag so it can reach

10:28 speeds in excess of 320 kmh or about 200 mph.

10:33 The aerodynamic elements do all appear to be

10:36 functional with outlets for the turbulent tire air, various cooling ducts,

10:39 and a hood scoop for cooling the top-mounted hot V turbochargers.

10:43 Now, speaking of turbos, let's chat about this engine.

10:46 So, we've got a 4 L twinturbo 90° V8.

10:50 Toyota says it's going to make 641 horsepower

10:53 or greater with 627 pound- feet of torque or greater.

10:57 It's going to have port and direct injection.

11:00 This is great.

11:00 I love this.

11:01 There's a lot of benefits to doing this.

11:03 I have a whole video explaining what they all are,

11:06 but another cool benefit is that it keeps your intake valves clean.

11:09 You don't have to worry so much about carbon deposits building up on them.

11:12 This engine also has a short stroke and a wide bore.

11:15 So, let's kind of look through some

11:16 other Toyota engines out there and compare it.

11:18 Starting with the Lexus LFA, 88mm bore with a 79 short stroke,

11:24 which allowed it to rev up to that 9,000 RPM.

11:28 Now looking at the GR Corolla, very similar in bore, but a longer stroke,

11:33 significantly longer stroke here, doesn't rev quite as high, 7200 RPM.

11:37 The GRGT matches the bore of the GR Corolla,

11:42 but uses a significantly shorter stroke.

11:45 So looking at that, you could kind of say, hey, look,

11:47 it looks a little bit like it's a bit of an 8 cylinder GR Corolla engine.

11:51 It does not appear to be related to their new 2 L turbo 4,

11:56 which could possibly be making up to 400 horsepower out of a little 2 L,

12:00 their G20E engine, which appears to have

12:02 a much longer stroke and a narrower bore.

12:06 So, looking at the GRGT,

12:08 one of the things I thought might be interesting is if we look

12:10 at their piston speeds and the RPM that their other engines are able to reach,

12:14 could we calculate perhaps where the red line is going to be for this GRGT?

12:19 So, if you were to assume it has

12:21 a similar average piston speed as the GR Corolla engine,

12:25 you could expect to see a red line of about 7,800 RPM,

12:29 which because it's turbocharged, I think it's probably going to be

12:31 closer to this than the naturally aspirated LFA.

12:34 But if it were to have piston speeds similar to the Lexus LFA,

12:37 well, then that would put it somewhere at about 8500 RPM.

12:41 Now, I think realistically somewhere around 8,000 would be feasible.

12:46 Now, that said, if it actually is revving

12:48 to 8,000 RPM and it's only making 641 horsepower,

12:51 well, then it's not going to be using that much boost.

12:54 So, I do think it is possible that this engine

12:56 could rev fairly high and I do think we're going

12:59 to see higher performance variants where we actually crank up

13:01 this horsepower number because it's going to have the capability.

13:04 Another cool thing looking at the transaxle

13:07 is how it enables a shorter wheelbase.

13:09 So, of course, the power comes from the engine

13:12 and travels to the back of the car,

13:14 connected by a wet clutch passing through the electric motor,

13:17 which can also supplement power and help reduce any perceived turbo lag,

13:21 as well as maintain positive torque during

13:23 shifts from Toyota's newly developed 8-speed automatic transmission.

13:28 And then the power reaches the back of the transaxle

13:31 and a pair of gears reverses the power

13:33 direction sending that power back towards the mechanical

13:36 limited slip differential which splits power between both wheels.

13:40 These conicle gears reversing the direction of the power

13:43 and sending it towards the front is

13:45 essentially what you'd see used in an all-wheel

13:47 drive vehicle to send power to the front axle.

13:50 Here it enables pushing the transaxxle towards the back of the car,

13:55 keeping weight on the rear axle,

13:57 improving power delivery while pushing the rear wheels forward,

14:01 enabling a shorter wheelbase and keeping

14:03 the overall length of the vehicle shorter.

14:05 So, a cool packaging solution.

14:07 And just a final comment,

14:08 Toyota really does seem to have done a good job keeping

14:11 this car simple in a world where cars are becoming increasingly complex.

14:15 It's using your typical coil springs for the suspension.

14:18 There aren't any active aerodynamic elements.

14:21 Straightforward overhead cam setup for the valveetrain using chain drives.

14:26 Nothing crazy going on with the turbos.

14:28 And sure, you have the hybrid system,

14:30 but Toyota has been cranking out dependable hybrid powertrains for decades.

14:34 So overall, it looks like this should have classic Toyota reliability,

14:38 which isn't always the case in the world of supercars.

14:41 Hopefully sometime I can get behind the wheel and tell

14:43 you if it drives as good as it looks.

14:45 If you have any questions or comments, feel free to leave them below.

14:48 Thanks for watching.

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