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So I took the Cayman S out for a spirited Sunday drive. I wasn't trying to push too hard (only got 500 miles on her), but after a rather delightful road, I was surprised to see the G-meter recording at 1.06 right and 1.02 left.

Never heard the tires squeal, nor did the PSM activate. (I was in Sport Plus, shifting manually so as to keep RPMs 4000 or below, sometimes 4500.) Nor did I feel the slightest instability.

What sort of Gs do you all regularly see on the road? On the track? Just curious as I've never owned a car with a G meter before.
 

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I have a 718 Base Boxster without PASM and without PTV. Tyres: have used Goodyear Eagle F1s, currently using Michelin PS4S. I love checking and resetting my max G force /forum/images/718forum/smilies/tango_face_smile.png

Under the assumption that the road is dry, and the tyres have been warmed up:
0.9G = zero slipping of rear end. "On rails"
1G = on a flat road (no camber) - very minor and completely controllable slip. I basically aim for this - fun minor controlled oversteer but very safe, lots of room for errors to be corrected. If corner has a positive camber = still "on rails"
1.1G = moderate slip on flat road, but still controllable.
1.2G = I'm no longer comfortable aiming for this (unless positive camber). Definitely not maintainable for an extended period.
1.3-1.4G = can't do this on a flat road at all. Only do this on my favourite roads / corners that I know well that have a positive camber.

I found the Goodyears (early in their life) and the Michelins had a similar maximum attainable lateral G force. As the Goodyears wore down they begun slipping more and more easily. However the Michelins give me a lot more confidence, I find the oversteer and correction of the oversteer is a lot more gradual, whereas there was a bit of snapping back into place with the Goodyears.

As you can probably tell... I sometimes greatly regret not optioning PASM and PTV on my car /forum/images/718forum/smilies/tango_face_smile.png As I could be pulling more Gs, and having more fun! Next car I definitely won't make the same mistake.

However whenever I drive my favourite corners, my car puts such a stupid grin on my face... I sometimes can't imagine being any happier. So then I regret nothing /forum/images/718forum/smilies/tango_face_smile.png
 

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After my first-ever autocross:



The left hand turn was new (it had been 1.22); the 0.96 braking used to be 0.77. Those previous highs were set at the Gap, I believe.

Car has PASM (autocross and Gap were hard, I remember) and PTV. PSM was full on. Tires are 20" Goodyears.

Edit: I remember a couple of 1.0X values on my first couple rides. I don't reset the G meter typically or intentionally, so I would guess those values occur regularly.
 

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i'm heading to mid-oio in a couple days and if the weather cooperates i'll see what i can pull. friday (open lapping day) looks like rain all day, saturday should be ok but more rain on sunday.
 

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Interesting data. Does the G meter automatically record for each trip or do you have to start it?

I went for a spirited drive last Sunday and really felt on the edge on a couple of corners. Would be interesting to know the Gs.
The G meter automatically records, but it only updates the maximum value if you exceed it. Thus the max value becomes pretty useless when it is reading 1.3x or greater. I reset the max values at minimum every trip, and usually after every 'fun' section of road. I like looking at the G meter for as many corners as I can, so I can configure my own internal G meter to be more and more accurate (ie I guess the Gs in my head, then look at the real value).

Your GTS (with its default Sports Chrono) should have the actual G meter (duegatti's picture) which you can display in the right side multifunction display. That has the real time G force data as well... but no way am I looking at that thing during a 1+G corner.

I don't have SC, so I use the central console screen (goldtrom's picture) where I have set the custom parameters as Max lateral acceleration and Max longitudinal acceleration. I have no real time G force display, but I just keep resetting the max values before every section of road that I am interested in.

For local corners and comparison - the max lateral Gs I get on McCarr's Creek Road around the tight hairpin sections in the eastern part of the road is around 1.2g (this assumes warm tyres, and optimum driving conditions). There is significant slipping of the rear end when doing so, particularly as I accelerate out of the apex and wish I had an LSD. Also I am in 2nd gear and not adhering to break in RPMs. I actually would like to see what your GTS with SPASM and PTV does when it is past break in... but in a way I don't... because then I might have this huge desire to get a car with PTV :)

I try to keep it to <= 1g for daily driving. Gives some room to adjust in case of obstacles.
View attachment 21600
Yeah I agree. I aim for =<1g for the daily commute for the exact same reason, correctability if anything unexpected occurs. And if it rains then I aim for nothing.
 

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For those without Sport Chrono, you can have live view on the PCM.
But it is kind of useless, to have the max setting is by far the best.
Even with live you on the MFD you dont have the time to look at it.


But SH with connect+ and you can record your drive and open it in Race Render and get all the info you need :)
 

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I just went out and checked my G meter, see photo below. I did notice it before but I agree there is no way I am going to be looking at that whilst cornering!

I assume 1.24 is G force on right hand corner and 1.3 is left hand corner. 0.79 I assume is acceleration which makes sense as I am still running in so relatively light throttle inputs.

Not sure what corner these were as it was a 480 km round trip on Putty Rd which is a well known drivers road in NSW Australia with some very long winding sections.

After the drive I did notice the outside edges of the Michelin PS4 tires were quite a bit scuffed so I was giving it a fair go on some corners but still getting the hang of the car. I assume at 1.3 G it was a reasonable effort.

One thing I notice about these cars is they feel so capable it is relatively easy to drive close to the limit where ever that is. Although if I could choose my tire sizes I would go slightly wider front and rear and maybe get Cup 2s. I did have the car step out on one corner and have under-steered a few times on tight downhill corners.

Incidentally there were quite a few RS3s on this drive. We were over-taking at times and the GTS was slightly faster than the RS3 despite my limiting to max 4000 RPM. :)
 

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Yes, 1.3 is turning to the left and 1.24 is to the right.

Im very impressed with the GTS pulling those numbers with you still in the break in period. The last time I was on putty rd i think i maxxed out at 1.2g. So SPASM and PTV is at the very least adding 0.1g, and then add a bit more for when you are allowed to push past 4k rpm. Although you are also probably a much better driver than me given your car history. So this isn't the most accurate of comparisons given driver skill is quite a large differentiating factor ?

0.79 longitudinal is definitely you being very disciplined with your break in!

I was having very similar thoughts about going cup2 next time - and being forced to go slightly wider since they dont have 235 widths for the front for 20".
So for 20" wheels they have 245 265 285 295 305 widths in 30 or 35 aspect ratios... what were you thinking for front and rear?
 

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All very interesting. But I don't think my car has any limits. At least, I haven't been able to find them. But then, I'm not usually looking very hard.


That real-time g display, is that in the normal gauge display? I don't think I've seen that option.
 

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All very interesting. But I don't think my car has any limits. At least, I haven't been able to find them. But then, I'm not usually looking very hard.

That real-time g display, is that in the normal gauge display? I don't think I've seen that option.
There is an option for that display the normal way of getting options, and you have a choice of seeing the current high count or clearing it. Hope that makes sense.
 

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Havn't uploaded a photo before so not sure if this will work. Wasn't sure how the numbers compared until seeing this thread - pleased, but also suprised to see I have the highest peak G so far.

It was only about 15 degrees, so there's certainly more to be found with heat in the asphault.

Vehicle is a '19 CGTS (Manual) and was first time on track with 'The Bullet'. :)
 

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saturday was the best day this weekend.


-edit-


for those worried the 2 notifications were for low fuel and no tpms in my track wheels :)
 

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