How much faster could GTE/GTLM go?

[Danathar]

I was wondering...

If there was the desire, how much faster could the current GT cars be designed to go (and survive endurance races). By faster I'm thinking of overall lap time?

I'm under the assumption that the current GTE/GTLM cars are specifically crippled as to not run into LMP2/LMP1 speeds. Is this true? If IMSA wanted to tweak the rules could the cars break the prototype track records on tracks in the U.S.?

[AoB Special Stage]

Without the air restrictors and with some fatter tyres, we should be able to run down P2 without too much difficulty, although the brakes would probably need an upgrade to boot.

[Artur]

Originally Posted by AoB Special Stage

Without the air restrictors and with some fatter tyres, we should be able to run down P2 without too much difficulty, although the brakes would probably need an upgrade to boot.

I highly doubt that!

GTs were 10s and 9s slower than P2s on Silv and Spa this year.

Fatter tyres would give what, 2s?

The biggest handicap of the GT cars is actually their weight. DTM probably have about the same power as GTs and they still are on par with LMP2s and the reason is obviously their 1030kg weight instead of 1250kg, or whatever, for the GTs(as DTM have spec Hankook tyres)

Originally Posted by DistortedSmile

IMO it would probably be very easy to get them to at least late 00's GT1 speed with more power and better tires.

better tires how, increasing width? Because, given their stint lengh, the current compounds are about as good as they currently can have

P2s will upgrade their power to 600HP next year, IIRC, so I guess GT500 won't be faster than them even on a place like Fuji(On Suzuka I doubt that would happen even as it is now)

[J Jay]

Apologies for the off-topic, but ...

Originally Posted by Artur

P2s will upgrade their power to 600HP next year, IIRC, so I guess GT500 won't be faster than them even on a place like Fuji(On Suzuka I doubt that would happen even as it is now)

Actually Fuji would be the first track - and not the only one, Buriram would be my other choice - where I would expect 2017 GT500 to be faster than 2017 LMP2. Don't forget GT500 run at/very close to 650hp with no plans to kerb that so far, and the target 25% downforce reduction will also come with a smaller but significant drop in drag.

And I would be confident that this year's GT500 (well, maybe not the NSX-GT...) would lap Suzuka faster than this year's LMP2.

[TRuss]

They can go as fast as the regulations allow.

[joeb]

That is a good question. In addition, I'd like to know what could be done to allow for faster times?

My take:

1)Carbon brakes
2)More aero freedom
3)Reduced minimum weight (not sure if ballast is currently being used)
4) and of course more power!

[Danathar]

Originally Posted by joeb

That is a good question. In addition, I'd like to know what could be done to allow for faster times?

My take:

1)Carbon brakes
2)More aero freedom
3)Reduced minimum weight (not sure if ballast is currently being used)
4) and of course more power!

Well, I'd imagine you would not want to go TOO far outside what is sold to consumers. I don't recall but isn't ABS and TC also banned in GTE/GTLM?

Upgrading to carbon brakes would be fine.

I think an article has been done before to compare the off the lot version of the Corvette vs the race version. But that was years ago. It would be REALLY interesting to see what the current crop of GTE/GTLM drivers could do lap time using an off the lot with all the options corvette compared to the IMSA spec version at one of the tracks they go to.

[joeb]

Originally Posted by Danathar

Well, I'd imagine you would not want to go TOO far outside what is sold to consumers. I don't recall but isn't ABS and TC also banned in GTE/GTLM?

Upgrading to carbon brakes would be fine.

I think an article has been done before to compare the off the lot version of the Corvette vs the race version. But that was years ago. It would be REALLY interesting to see what the current crop of GTE/GTLM drivers could do lap time using an off the lot with all the options corvette compared to the IMSA spec version at one of the tracks they go to.

In 2012 Road and Track did such a comparison.

http://www.roadandtrack.com/new-cars...e-gt-showdown/

Didn't compare tech too much, but did care laptimes

[Danathar]

Originally Posted by joeb

In 2012 Road and Track did such a comparison.

http://www.roadandtrack.com/new-cars...e-gt-showdown/

Didn't compare tech too much, but did care laptimes

Clicked on it again but the sections where the stories are a dead (links don't work). Content aint there no more

[JHamilton]

Originally Posted by Danathar

Well, I'd imagine you would not want to go TOO far outside what is sold to consumers. I don't recall but isn't ABS and TC also banned in GTE/GTLM?

Upgrading to carbon brakes would be fine.

I think an article has been done before to compare the off the lot version of the Corvette vs the race version. But that was years ago. It would be REALLY interesting to see what the current crop of GTE/GTLM drivers could do lap time using an off the lot with all the options corvette compared to the IMSA spec version at one of the tracks they go to.

I think they are hedging the GTLM cars back too far from their street counterparts, with respect to power anyway.

For whatever it is worth, Randy Pobst did a 1:33.005 in a Z06 and a 1:33.29 in a 991 GT3 at Laguna Seca last year. Qualifying times were 1:23.39 and 1:23.96 respectively for their GTLM versions this year.

[MaskedRacer]

Originally Posted by JHamilton

I think they are hedging the GTLM cars back too far from their street counterparts, with respect to power anyway.

For whatever it is worth, Randy Pobst did a 1:33.005 in a Z06 and a 1:33.29 in a 991 GT3 at Laguna Seca last year. Qualifying times were 1:23.39 and 1:23.96 respectively for their GTLM versions this year.

Daytona is a good example of a this. The GTLM cars have frequently gone through the infield section keeping a nearby DP/LMP2 car behind it. Then when they get on the oval/banking, that is where the prototype cars shoot off in the distance.

[DistortedSmile]

IMO it would probably be very easy to get them to at least late 00's GT1 speed with more power and better tires.

Originally Posted by Danathar

It would be REALLY interesting to see what the current crop of GTE/GTLM drivers could do lap time using an off the lot with all the options corvette compared to the IMSA spec version at one of the tracks they go to.

Any GTE car would absolutely demolish it's road car counterpart at any track, even the the track version of the Mclaren P1 hypercar is slower than the GT3 650S.

Some lap times from Spa for comparison:
GTE/GT3:
Ferrari 488 GTE - 2:17.632
Ford GT GTE (including sandbag ballast) - 2:18.163
Audi R8 LMS GT3 - 2:18.505


Roadcars:
Koenigsegg One:1 - 2:33.00
McLaren P1 - 2:38.00
Chevrolet Corvette ZR1 - 2:41.69

[FormulaFox]

There's a lot of untapped potential in these classes - GT3 in particular. The "Super GT3" idea briefly became a popular what if idea amongst engineers for exactly that reason - some looked at how much you could change before elevating things to an unsustainable level, some looked at how little you could get away with changing to achieve a particular performance gain.

Regardless, both classes could, without too much difficulty, be bumped up to current LMP2 speeds with a bit of work if someone wanted to go that far.

Can't recall where, but I did once(before talks of speeding up the classes began making serious rounds) read that with aerodynamic and suspension improvements(as in to the level of making the cars look VERY DTM-like) a 15% increase in GTE pace at Le Mans could be achieved on the same tires and brakes.

[Carbone]

Originally Posted by DistortedSmile

Some lap times from Spa for comparison:

GTE/GT3:

Ferrari 488 GTE - 2:17.632
Ford GT GTE (including sandbag ballast) - 2:18.163
Audi R8 LMS GT3 - 2:18.505

Spa Francorchamps 2016 :

GTE (WEC) = 2’17’’632 (with Michelin tires confidential)

GT3 (GT Open) : 2’15’’746 (with Michelin tires customers)

GT3 with Michelin tires confidential = 2’14’’ - 2’15’’

[Mitchi_S]

Originally Posted by Carbone

Spa Francorchamps 2016 :

GTE (WEC) = 2’17’’632 (with Michelin tires confidential)

GT3 (GT Open) : 2’15’’746 (with Michelin tires customers)

GT3 with Michelin tires confidential = 2’14’’ - 2’15’’

Which GT3 car did a 2.15 at Spa? That must be the fastest GT3 time I've ever seen in Spa. That's basically GT1 pace.

[rich07]

Would love to see what the new 488 could do with no restrictors and the boost wound up. Wouldn't sound as good as a Prodrive 550 though

[MagVanisher]

If the GTE/GTLM cars go faster in the next two or three years, will it be up to par or potentially take over against LMP2 in terms of speed?

[Coach Ep]

Originally Posted by MagVanisher

If the GTE/GTLM cars go faster in the next two or three years, will it be up to par or potentially take over against LMP2 in terms of speed?

P2 is supposed to make a significant step up in speed next year which might open the door for GTE/GTLM to go a bit faster as well.

[TF110]

The mid-late 00's gt1's were doing sub 3:50's at LM. The tires are better today. The cars are about 100kg heavier and -100hp. I think the modern cars have plenty of upside to them (maybe not the Porsche and Aston Martin).

[joeb]

Originally Posted by TF110

I think the modern cars have plenty of upside to them (maybe not the Porsche and Aston Martin).

Right, but you said modern cars!

[Artur]

Well, I know for sure that P2s are massively faster than GT500s on high speed corners like Coca-Cola and 100R and, as Suzuka has shorter straights and faster corners, that would favour P2s a lot.

I already posted this before, SGTs are much closer to SFs on Fuji than on Suzuka. Best time SGT ever did on Suzuka was 1.47.6 while SF's best was 1.36.9. On Fuji, SGT's best is 1.27.5 and SF's is 1.22.5.

5s gap on Fuji(6% more) and 10.5s on Suzuka(11% more)

Additionally, if we assume P1-Hs would lap around the same as SF on Suzuka, then, applying Silverstone percentage(from P1-Hs to P2s) we could predict a P2 laptime of ~1.45.3 on Suzuka.

This is just some very rough extrapolation, obviously, but I just did it to show that my claim is not far-fetched

[J Jay]

Originally Posted by Artur

Well, I know for sure that P2s are massively faster than GT500s on high speed corners like Coca-Cola and 100R and, as Suzuka has shorter straights and faster corners, that would favour P2s a lot.

I already posted this before, SGTs are much closer to SFs on Fuji than on Suzuka. Best time SGT ever did on Suzuka was 1.47.6 while SF's best was 1.36.9. On Fuji, SGT's best is 1.27.5 and SF's is 1.22.5.

5s gap on Fuji(6% more) and 10.5s on Suzuka(11% more)

Additionally, if we assume P1-Hs would lap around the same as SF on Suzuka, then, applying Silverstone percentage(from P1-Hs to P2s) we could predict a P2 laptime of ~1.45.3 on Suzuka.

This is just some very rough extrapolation, obviously, but I just did it to show that my claim is not far-fetched

This is all sensible (and I'm enjoying the extrapolation!) but I'd question the assumption here. As you say, Suzuka's layout significantly favours LMP2 over GT500. But I would add that it also significantly favours SF over LMP1-H for the same reasons - the much lighter car would get round the corners faster, given similar levels of downforce.

With that in mind I added 6% for an assumed LMP1-H Suzuka lap of 1:42.7, and then used the Silverstone times to get an assumed LMP2 lap of 1:51.5, right in the middle of the fastest race laps set in last year's Suzuka 1000km.

Huh. That'd be an interesting one-off showdown.

BTW, were you using fastest race laps throughout? My percentages were slightly different to yours so I was wondering whether it was due to this or if we were using different year's races.

[carbsmith]

Weather has a huge effect on lap times in Japanese series, since they will race at the same track in weather ranging from about +10C to +40C.

Super Formula races at Suzuka in early spring and late fall while the Suzuka 1000 is usually the hottest Super GT race of the year. The Fuji 500 and Fuji 6 Hours are quite cool races while the Super Formula race and Fuji 300 are during the hot season. As such the qualifying times for the Fuji 300 are always a second or two slower than the Fuji 500.

[Artur]

Originally Posted by J Jay

This is all sensible (and I'm enjoying the extrapolation!) but I'd question the assumption here. As you say, Suzuka's layout significantly favours LMP2 over GT500. But I would add that it also significantly favours SF over LMP1-H for the same reasons - the much lighter car would get round the corners faster, given similar levels of downforce.

With that in mind I added 6% for an assumed LMP1-H Suzuka lap of 1:42.7, and then used the Silverstone times to get an assumed LMP2 lap of 1:51.5, right in the middle of the fastest race laps set in last year's Suzuka 1000km.

Huh. That'd be an interesting one-off showdown.

BTW, were you using fastest race laps throughout? My percentages were slightly different to yours so I was wondering whether it was due to this or if we were using different year's races.

Oh yeah, the assumption I made is totally questionable. It was just to show a rough extrapolation. If I were to bet, I would expect the SFs to lap slightly faster than the P1-Hs. By slight I mean no more than a couple of seconds, though. The SFs are definitely a bit faster on the high speed corners and likely on the slow stuff too(I imagine they have softer compounds due to less weight and shorter stint) while the P1-Hs advantage lies on acceleration(hybrid) and low drag(covered wheels). I think the P1s would make up some of the time lost on corners but not all so a few seconds would be left between them and SF, imho.

In 2006, F1 was around 1.29.8 on Nurb's Q3 and around the same on Suzuka's Q3. The layouts are quite different and that will affect the relative performance of each car to some extent but I'll assume here that not by huge amounts.

Conditions this year were less than ideal during Nurb's QLF, so let's suppose the R18 could do at least 1.38.0 as DiGrassi did 1.38.7 on a damp/green track. Going by that, I would imagine a R18 laptime on Suzuka to be on the same ballpark and the best ever SF time was a Lotterer pole from a time ago(1.36.9). A lot of times, the SF pole was around 1.38 so that's why I think that the extrapolation I originally posted is not totally unreal.

Btw, it would be so great if Toyota owned Suzuka instead of Fuji

In my extrapolation, I used the P1-H's and P2's fastest race laps because QLF was on wet. For the SF and SGT, I picked only the fastest time ever(QLF) for each series which covers the concerns carbsmith had about different weather and etc(as I looked into several sessions held on different climates and etc)

I did the extrapolations again and the numbers match with yours'. I guess you saw some difference because I applied the Silverstone % over a laptime of 1.37(I rounded to 97s as for the SF/P1-H assumed equal time) instead of the actual 1.36.9 that Lotterer did(a Q2 time btw, his pole was 37.0). Maybe that's the difference?

[TF110]

P2 is slower than gt500 in nearly every aspect. Plus they're 100+kg lighter. If GTE were 1000-1100kg with more power, they'd be really close to current lmp2.