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Discussion Starter #1 (Edited)
O.K. guys (and gals) I got a 1.4 lateral G-force reading on crappy Pzero street tires in the CGTS at Lightning (a small race track in New Jersey). I was running good lap times but this reading seems very high given the Pzero tire capability and magazine instrument testing that has the Cayman S at 1.0 max lateral G. Any ideas on the accuracy of the Porsche sport chrono G-force meter? Is it for entertainment purposes only?

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If one of your track buddies has something like an AiM Solo, maybe you can borrow it to compare.

That said, magazine testing is on a level surface. Tracks often have banking which can allow you to take the corner faster than you could if it was flat.
 

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Discussion Starter #3
If one of your track buddies has something like an AiM Solo, maybe you can borrow it to compare.

That said, magazine testing is on a level surface. Tracks often have banking which can allow you to take the corner faster than you could if it was flat.
Great point vantagesc! Banking is significant in the bowl at Lightning and at Turn 1 you are basically turning into a hill giving higher laterally G's.
 

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I've been wondering the same.

I got a 1.13G reading just taking bend to enter the highway.
 

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I would assume it is as accurate as base and S versions with the Sportschrono. :)

There was a thread a few months ago where someone compared it with his Aim Solo and they were very close indeed.
 
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I think the Cayman's G-meter is like a country club scale in the locker room. It always reads light to make members feel good. In the caymans case it makes owners feel good that their cars are pulling big G's. carl
 

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Recall that peak G's (which the car is showing I believe) is different than sustained G's (which is what magazines test on a skid pad).

You could probably get even greater G's showing on the car during break-away on a BIG, high-speed slide (might end ugly tho)! ;)
 

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If one of your track buddies has something like an AiM Solo, maybe you can borrow it to compare.

That said, magazine testing is on a level surface. Tracks often have banking which can allow you to take the corner faster than you could if it was flat.
Not sure I understand the physics. The G meter doesn't know which way is down, only which way the car's floor is. But come to think of it, a banked curve gives you more downforce. Ah, now I get it. Never mind.
 

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The G-Force display is just an afterthought to the real function of the sensors which is input into the PSM system.
In my experience there is a definite difference that PSM will allow between SPORT and SPORT PLUS.
I have yet to turn PSM OFF to determine max G-Force and doubt I ever will.-Richard
 

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I've run Lightning several times. Here's some data from my AiM Solo: Lightbulb 1.51, turn 2-3 combo 1.35, turn 4 (over the hill) 1.26. Track prepped 2007 Cayman S with R comps and suspension.
 

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Just wanted to add in some info from my suspension sponsor in autocross some years ago. He instrumented an Impreza STi with a race suspension and Hoosier autocross tires, and was measuring lateral G spikes as high as 1.6 G.

However, those numbers are seen in transition and not sustainable. I think the best sustained numbers he saw on those tires were 1.2 - 1.25 Gs.

So I totally believe the concept that a stock Cayman GTS on stock tires could hit a G spike as high as 1.4 G. But it won't hold that. The car may only hold that until the springs settle into their loaded position, then you're going to back to around 1.0 G.
 

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I'd agree with the commenter saying it was high peak G-s that you achieved on a banking.
 

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Mine was reading 1.05G on the skid pad but I am lowered on H&R springs with pasm also on more than half gone P Zeros.


The some of 911's in our group had readings as high 1.14G on the skid pad.


Sent from my iPhone using Tapatalk
 

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I got this on a sharp canyon road turn..
2016 Cayman GTS... Factory 20" rims and tires...PDK......PASM sport .....NO PTV. PSM off.....

I am having my car's suspention retrofited with x73 ... Wonder if it will improve cornering g-force ?

I never use the instrument cluster g-force display... I find it to be very distracting.. At least so far....
 

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I got this on a sharp canyon road turn..
2016 Cayman GTS... Factory 20" rims and tires...PDK......PASM sport .....NO PTV. PSM off.....

I am having my car's suspention retrofited with x73 ... Wonder if it will improve cornering g-force ?

I never use the instrument cluster g-force display... I find it to be very distracting.. At least so far....
The highest I've seen on my car is 1.32. Your gage must be faulty. It would be inconceivable (and impolite) for you to have generated higher values than I have.
 

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The X73 will decrease body roll. Whether that improves max lateral acceleration depends mostly on your camber settings. However, chasing peak lateral acceleration isn't really what it's about. It's nice for bench racing and discussion, but the fact is that if you really set the car up to maximize lateral Gs, you're probably suffering in some other areas like transitional behavior and straight line braking.

Here's my contribution to the G-force meter pictures...

11539746_10205808880335713_7994234857752793318_n.jpg

That was at an autocross last year on brand new Bridgestone RE-71R tires. Nearly took top time of the day at that event.
 

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The highest I've seen on my car is 1.32. Your gage must be faulty. It would be inconceivable (and impolite) for you to have generated higher values than I have.
LOL JQ...
My Appologies ...I have to work on my manners !
That said..
I have only had that result twice ...
1.4 is relatively easier to get.
1.3 is mostly the norm when i'm driving aggressively.
I think the 1.5 happened after the rear traction broke loose for a split second and locked back in.. Resulting in a strong lateral jolt.
Just guessing...

Cheers :)
 

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The X73 will decrease body roll. Whether that improves max lateral acceleration depends mostly on your camber settings. However, chasing peak lateral acceleration isn't really what it's about. It's nice for bench racing and discussion, but the fact is that if you really set the car up to maximize lateral Gs, you're probably suffering in some other areas like transitional behavior and straight line braking.

Here's my contribution to the G-force meter pictures...

View attachment 96369

That was at an autocross last year on brand new Bridgestone RE-71R tires. Nearly took top time of the day at that event.
Wow..JB... 1.6 ... Awesome!!! Was that on x73s? What size tire? 265/30/20? Do you have PTV?

I dont tune my car for g force at all.. Actually my car was/is on stock settings... I just enjoy pushing that envelope once in a while.:)
As we speak my car is being retrofitted with x73 by Porsche of Passadina CA and should be done by Thursday.... Its going to be alligned according to porsche standard x73 settings... No extra camber/toe or anything.

Now you have given me a new target .. LoL ...

Where do u go for Autocross?
 

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