GT4 video of 7:42 Nordschleife - Supertest sport auto

GT4 video of 7:42 Nordschleife - Supertest sport auto

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Goofnik

216 posts

141 months

Sunday 19th April 2015
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Phooey said:
Nearly as quick as a 991 C2s
No, quicker. Here are the same driver’s times in other cars. The GT4 2 seconds ahead of a 991 C2S.

EricE said:
Even more understeer!? Correct me if I'm wrong but the car in the video seemed to have massive amounts of understeer for a mid engined platform.
In stock config, it does have a bit of safety understeer with the default anti-rollbar positions. Set the front anti-roll bar in the soft position and the rear one in the stiff position and it'll be a lot more oversteer. The Cup2s, significantly increased section width, and different suspension (compared to the “Sport Chassis”/X73 Sport Suspension) keeps the GT4s a LOT more hooked up than an S/GTS. "Sport Chassis"-equipped cars are deliberately set up to be very slidey (ask me how I know! biggrin )

JeffC said:
but its not just time changing gear, ratios on the PDK are a lump lower than the manual or they are on the two cars I currently own, think 2nd gear is something like 20mph shorter on the PDK to the manual .
Have a GTS which is geared identically to a GT4. Nowhere near that huge a difference. 82-83mph is top of 2nd in a manual, 78mph in PDK. Third is more pronounced, where top of 3rd in the manual is around 112mph whereas it's around 103mph with PDK. Supposedly the reason for 2nd's gearing being kept the same in the GT4 is Andreas Preuninger likes passing slower traffic on normal roads at full chat, which that gearing always allows him to do.

Moreover, watch the comparison between a GT4 and a PDK-equipped 991 Carrera4 GTS. Unsurprisingly the Carrera4 GTS takes it to 60mph (AWD, PDK, greater rear weight bias, more top end, more torque), but the GT4's 60mph-150mph is quicker -- by the time the Carrera4 GTS PDK hits 240kph, the Cayman GT4 has nearly caught up at 238kph: https://www.youtube.com/watch?v=Do0JR__ZA84

Edited by Goofnik on Sunday 19th April 00:25

fioran0

2,410 posts

173 months

Sunday 19th April 2015
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rosino said:
How difficult is it to modify/shorten the final drive? I thought as opposed to single gears ratios it was relatively simple to achieve ?

Also the last 997.2 GT3 suffered from same issue which was solved in the the RS by lower final drive and longer 6th to compensate. I think I had heard of GT3 owners fitting the RS final drive and leaving the 6th alone as 300kmh+ opportunities don't abound in real life.

Or is it an impossible mod to achieve economically ?
The 997.2 RS only had a lower final drive (3.89 v 3.44). The 6 gear ratios themselves were the same in the GT3 and the RS.
As for the difficulty in shortening the final drive for the Cayman. Someone needs to make one first. AFAIK there is no one with a reliable R&P for that gearbox and I haven't heard of anyone looking into doing one.
You could re-gear the box to get round the ratios to some extent. I know GT gears made a set of gears for BGB in their rolex Cayman that had good longevity.

I am totally off reservation here as Caymans aren't my thing, but as I understand it, this gearbox has the same issue that all the street gearboxes have; namely that 2nd gear is fixed to the main shaft along with 1st. The race gearboxes have them removable. This means that you cannot change out 2nd gear in a simple fashion but instead are required to work around this fixed point. How big an issue this is will depend on what you want to run on the rest of the gears and what you want from the car but it's worth a mention.
That being said, the other gears already exist as does an LSD that does something rather than the "do nothing, let the brakes act as the diff LSD" fitted if one actually wanted to look at sorting things out.

On the flip side of all of this is the hard reality that that guy managed a 7.42 in the stock car with the stock ratios. If a new owner can't put that in then they probably don't need to be worrying too much about the long gear ratios holding them back just yet.

Edited by fioran0 on Sunday 19th April 01:28

bcr5784

7,115 posts

146 months

Sunday 19th April 2015
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fioran0 said:
The 997.2 RS only had a lower final drive (3.89 v 3.44). The 6 gear ratios themselves were the same in the GT3 and the RS.
As for the difficulty in shortening the final drive for the Cayman. Someone needs to make one first. AFAIK there is no one with a reliable R&P for that gearbox and I haven't heard of anyone looking into doing one.
You could re-gear the box to get round the ratios to some extent. I know GT gears made a set of gears for BGB in their rolex Cayman that had good longevity.



Edited by fioran0 on Sunday 19th April 01:28
987 Caymans in the Pirelli World Challenge series are allowed a 4.222 diff - so presumably one exists, though whether it is suitable for a 981 road car I've no idea.

HokumPokum

2,051 posts

206 months

Sunday 19th April 2015
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juansolo said:
So... How a car, not built to be optimal around a pointless ribbon of tarmac in Germany, goes around said pointless ribbon of tarmac really does define what people want these days. Thank you for contributing to the problem.

Porsche can't win. PDK gives 15 secs WE WANT PDK. But PDK is less involving WE WANT MANUAL. I know the solution is to offer both. But still, I find it amusing.

Also, let's get back to the Nurburgring. Those who find 15 seconds, so a little over 1 second a mile, reasons to go on about PDK or the super long gearing (that no-one noticed on the first two generations of the car) seem to be missing the point that it's a circuit that probably 1% of track drivers can actually set consistent fast times on. Mainly because it's so fking dangerous, it requires you to either be massively talented with big balls, or just a psycho with no fear of death.

Alternatively we can all just get our knobs out and slap them on the table and see who's got the biggest cock once and for all, because that's ALL that this is. It's utterly fking irrelevant unless you're planning on racing it, and if you were, one of the first things to go would be the gearbox anyhow, along with all the options people fret over, and the resale value. Basically this is a car that's designed for lucky, wealthy peeps to driver over to Spa, do a few laps with some chums and drive back again. How fast it goes round is irrelevant isn't it as long as it's a blast? Because there's always going to be some bd in a Radical or slicked up Caterham that's gonna be way quicker anyhow. So what's the actual point in arguing over a little over 1 sec a lap when they'll be 10sec up a lap around Spa, never mind the Ring.

I really do wonder what people want from cars these days and what pleasure they derive from increasingly lardy, grippy, powerful machines that we, as consumers, keep demanding. When will it end? We're already at 200mph & 600+ hp on estate cars for fks sake.
I think it is simple we want a new category for manuel cars with 3 pedals.

I hear about the HP, but fast cars can still be involving much as slick on race cars can be fun. To those that want the ultimate, isn't it great? To those that don't need it or predominantly use them on the road, there's a whole variety of cooking versions that will do nicely w/o the manhood display.

HokumPokum

2,051 posts

206 months

Sunday 19th April 2015
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juansolo said:
isaldiri said:
juansolo said:
So... How a car, not built to be optimal around a pointless ribbon of tarmac in Germany, goes around said pointless ribbon of tarmac really does define what people want these days. Thank you for contributing to the problem.

Porsche can't win. PDK gives 15 secs WE WANT PDK. But PDK is less involving WE WANT MANUAL. I know the solution is to offer both. But still, I find it amusing.
.
Bad excuse to go on an anti ring time rant surely. So far, the main issue noted seemed to be that the gearing looks overly long and then it got into a discussion into how much pdk would change the ringtime rather than lamenting lack of pdk makes it slow (7:42 hardly is slow either....) Most people don't seem to be clamouring for pdk to make the car quicker, merely shorter ratios to make the car a better one to drive....you can't possibly not be surprised by the amount of the lap done in 2nd gear and think the car might be better with shorter ratios, not just faster but better full stop.
I find people complaining about the ratios comical when they're the same ratios we've always had, just with a more powerful and slightly higher revving engine. Be happy it's got a manual.

There's just no pleasing people. Which I expect is exactly what Porsche's motorsport division would feel reading this thread.
long ratios not bad on track, less shifting.

juansolo

3,012 posts

279 months

Sunday 19th April 2015
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isaldiri said:
juansolo said:
I find people complaining about the ratios comical when they're the same ratios we've always had, just with a more powerful and slightly higher revving engine. Be happy it's got a manual.

There's just no pleasing people. Which I expect is exactly what Porsche's motorsport division would feel reading this thread.
Simple question - do you think the gt4 could be a better car with shorter ratios? I am glad the car is manual only, however i don't see any contradiction hoping it could be the best it could be.
You've got to accept that it's never going to be everything it could be due to it's position in the product range. So in a way, it is the best it could be...

juansolo

3,012 posts

279 months

Sunday 19th April 2015
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Jim1556 said:
As for Mr 'pointless ribbon of tarmac', he's obviously not been! rolleyes
I have, twice (photographic evidence here from the first time: http://juansolo.co.uk/motas/bbt5.html). Still think it's pointless for many reasons. Firstly it's not representative of any road or other race track out there, in that respect it's unique and in the real world proves nothing. It's unique nature means building a car to go fast around there compromises it for everywhere else. Which is why when people put so much emphasis on lap times there, it makes me wince. The only point of the Nurburg ring is willy measuring. Even Derek Bell reckoned Stefan Bellof disconnected his brain to set that lap around it.

It's an experience, don't get me wrong, and I suspect if you lived near there, it'd be a lot of fun. But from the point of view of actual track driving, Spa or Mugello makes it look st.

Edited by juansolo on Sunday 19th April 09:00

fioran0

2,410 posts

173 months

Sunday 19th April 2015
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bcr5784 said:
987 Caymans in the Pirelli World Challenge series are allowed a 4.222 diff - so presumably one exists, though whether it is suitable for a 981 road car I've no idea.
Note that I said "reliable" in my post. I know of one car that ran a shorter R&P in World Challenge last season though there could have been more. They were only managing to get a single race out of the R&P.

bcr5784

7,115 posts

146 months

Sunday 19th April 2015
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fioran0 said:
Note that I said "reliable" in my post. I know of one car that ran a shorter R&P in World Challenge last season though there could have been more. They were only managing to get a single race out of the R&P.
Odd that a team has just requested and been granted permission to run that diff in the GTS class http://www.world-challenge.com/index.php?option=co... so it will be informative to see how they get on.

Jim1556

1,771 posts

157 months

Sunday 19th April 2015
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juansolo said:
I have, twice (photographic evidence here from the first time: http://juansolo.co.uk/motas/bbt5.html). Still think it's pointless for many reasons. Firstly it's not representative of any road or other race track out there, in that respect it's unique and in the real world proves nothing. It's unique nature means building a car to go fast around there compromises it for everywhere else. Which is why when people put so much emphasis on lap times there, it makes me wince. The only point of the Nurburg ring is willy measuring. Even Derek Bell reckoned Stefan Bellof disconnected his brain to set that lap around it.

It's an experience, don't get me wrong, and I suspect if you lived near there, it'd be a lot of fun. But from the point of view of actual track driving, Spa or Mugello makes it look st.

Edited by juansolo on Sunday 19th April 09:00
Fair enough, it's not for everyone. But it is a Damn good comparison for highlighting a car's weaknesses though.

Plus, the atmosphere, people you meet and cars you see there - no other place like it...

fioran0

2,410 posts

173 months

Sunday 19th April 2015
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bcr5784 said:
Odd that a team has just requested and been granted permission to run that diff in the GTS class http://www.world-challenge.com/index.php?option=co... so it will be informative to see how they get on.
Jack Baldwin ran a shorter R&P last year in his car in WC. It was made by EMCO and they were getting a race out of one. It doesn't seem to be any secret as far as I can tell. I'm sure if you ask around you can find out more.
As I previously said, Caymans aren't my thing so I'm off reservation with them to some extent. This was just something I knew from wider discussions.
Given the WC races are capped at 50 mins. An R&P that knocks itself to death over a race weekend give or take is not something I would consider reliable in a wider context. Should make a great mod for a GT4 or other road going Cayman!!

Regarding your link, an optional final drive has always been allowed as per the rules in WC afaik. All that VTS change request seems to be doing is fixing the optional final drive allowed as per rules section 2.5.2 to a ratio of 4.22. The Cayman VTS sheet for 2015 now lists 3.875 and 4.22 as being the approved options for those cars.
Note it was PMNA that requested this, not a team. Odd in what way?


Edited by fioran0 on Sunday 19th April 12:51

bcr5784

7,115 posts

146 months

Sunday 19th April 2015
quotequote all
fioran0 said:
Jack Baldwin ran a shorter R&P last year in his car in WC. It was made by EMCO and they were getting a race out of one. It doesn't seem to be any secret as far as I can tell. I'm sure if you ask around you can find out more.
As I previously said, Caymans aren't my thing so I'm off reservation with them to some extent. This was just something I knew from wider discussions.
Given the WC races are capped at 50 mins. An R&P that knocks itself to death over a race weekend give or take is not something I would consider reliable in a wider context. Should make a great mod for a GT4 or other road going Cayman!!

Regarding your link, an optional final drive has always been allowed as per the rules in WC afaik. All that VTS change request seems to be doing is fixing the optional final drive allowed as per rules section 2.5.2 to a ratio of 4.22. The Cayman VTS sheet for 2015 now lists 3.875 and 4.22 as being the approved options for those cars.
Note it was PMNA that requested this, not a team. Odd in what way?


Edited by fioran0 on Sunday 19th April 12:51
Thanks for that. Interesting and informative stuff. As you say an optional diff ratio is allowed in the regs - I only thought it odd that there was a request to use this particular ratio if the diff in question was known to be unreliable.