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Collected my 997.1 GT3 today!

After almost 6 years, I finally got new wheels. Part of the reason took so long is I couldn't find a wheel design I actually liked the look of (... and weren't crazy expensive...). Enter ... OZ Leggera which came out last year i think, or at least that's when I found out about them...

My weight savings for anyone interested in that sort of thing (courtesy of the bathroom scales):

F - 18.5 kg - Leggera + 245/35/19 Cup 2
R - 22 kg - Leggera + 305/30/19 Cup 2

F - 20.5 kg OEM + 245/35/19 Super Sport
R - 25.5 kg OEM + 305/30/19 Super Sport

So looks like 7 kg and 4 kg per axle saving, 11kg altogether. Does anyone know what the rotational mass weight saving multiplier is, seems lots of contradictory views on the Internet ...

I'll take more pics when the weather improves, not the best weather today to go for a drive on un-bedded Cups
 

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Cheers Stu, looking forward to going for a drive, maybe tomorrow hopefully. Sundeep reckons unsprung multiplier thingy is 6, so 11kg x 6 = 66kg weight saving over the other set of wheels. I'm intrigued to know how different the car feels compared to the old wheels 8)
 
Nice - they work well. With that much weight out of the corners you should easily feel it, especially in the corners on turn in. :thumb:
 
Great combo. Just needs the JPS logo now. :thumb:
 
The wheels are lovely Roro, really suit the car :thumb:

It is quite tricky to work out the static to rotating mass effect from a simple 11kg less = 'x' difference. Where the mass has been removed from i.e the further the distance from the centre where is the force is applied is where it really matters. You could have fitted heavier wheels but all the weight is around the wheel bolts and lost say 5kg from the outer part of the rim and this would massively reduce the gyro effect and feel much sharper even though the overall weight of the wheel is heavier. It would be great if you could report back and let us know what difference you feel with these lighter wheels.
As a simple calculation I would be looking more towards a factor of 2-3 rather than 6 with respect to the effect on acceleration (and braking). The improvements in handling from carrying less unsprung weight is dramatic; your suspension becomes more responsive and the the bumps become less traumatic.

The next time I drive my 996 I would have removed 36.2kg of unsprung mass (4.4kg Ohlins, 1.2kg Coffin arms, 2kg Ti bolts, 5kg Brakes, 23.2kg Wheels/tyres, 0.4kg brake shields) since I last drove it. So hearing how you get on will give me some indication as to what to expect :thumbs:

Agree with Senoj:
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Car looks really good !....dem' wheels look the business. 8)
 
:thumbs:

Here's a few more pics

Was out and about today, and I am pleasantly surprised by the improvements in acceleration, braking and going round corners as Disco pointed out. Can't wait to try this setup out on track!

Even based just on road driving, car definitely feels much lighter, it's definitely a difference you can feel through the drivers seat. Felt easier to move off the line, easier on the clutch for instance, but that could just be the placebo effect

I'll investigate titanium bolts as I've had to reuse my old bolts and they look... bad. They've corroded horribly over the 10 years since the car was made so time for a refresh

JPS... it did cross my mind but I'll give the decals a miss, been there done that :grin: ... also if I went and put the old wheels back the car might look a little odd!

I'm liking the Cup 2's as well, they're quieter than I remember my old Cup tyres being years ago, and they feel more direct than the Super Sports (maybe that's because they're harder plus it was only around 2/3C today). They seemed a bit quieter than the Super Sports too come to think of it which surprises me

I'll report back again after I do a trackday or 2, hopefully won't be too long after the weather improves
 

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Looks great Ro' :thumbs:
 
Regarding the Supersports, having come from the PS2's i used to run them at 36psi cold as found it was more road friendly/compliant - they then heated up. I then tried the same method with the SS's as they quickly got upto 39 PSI (according to my aftermarket tyre sensor thing).

However i found the rears still quite 'squishy' and the tail abit more happier shall we say - not a comforting thought for me, on the road with curbs and probably lack of skill to catch it.

Now run the tyres at the recommended warm pressures when cold and has stiffened the sidewall up/prefer it for my driving style. I believe the SS get replaced this year
 
Cheers Terry :thumb:

Kingston, yep PS4 replaces PS3 and SS. Not sure about availability though, but I'll be sticking with the Cup 2's and SS sets I have for the time being
 

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