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-   997 (https://www.6speedonline.com/forums/997-31/)
-   -   I finally did it, yeah i'm an heretic... (https://www.6speedonline.com/forums/997/211788-i-finally-did-yeah-im-heretic.html)

utkinpol May 26, 2010 07:57 AM


Originally Posted by jon8 (Post 2852629)
I agree with you. And i'll be very gentle on the first wet road i'll get. I'm undecided yet about trying 325-25-20 Pirelli on rear wheels because i'm a bit worried to lose the great balance (w/just a bit of oversteer) i have right now.

What i should do, also, is trying a set of 18's (all corners) with R compound tires to have a real "racetrack" reference.

some people run A6 hoosiers in front with R6 in rear on a track but those people usually are quite knowledgeble about what is it they do and what for and how all that works in combination with other suspension adjustments.

none ever uses different rims diameter. again, for street car it all does not matter much but I would think you deteriorated rear axle quite much with those 20" rims, if you have stock shocks in rear and stock sways. with stiffer shocks it probably would give less problems but still, it is just a silly bling.

tr_dlite May 29, 2010 02:18 PM

Sorry to burst your bubble but I don;t like the color combo. I guess it is in the eye of the beholder... Enjoy!

wolfnards Jun 2, 2010 06:41 AM


Originally Posted by cbzzoom (Post 2848239)
I've been thinking of trying 18 front and 19 rear for a while.

I always thought the wives tales about matching front & rear tire brands was a lot of hooey. The fact is the traction characteristics of the front & rear on the 911 are so vastly different that adding another difference is not a big deal. On a balanced car like a Cayman I think you would notice it a lot more.




Interesting. I thought the mismatching tires/wheels would be an issue, but found that the Lotus Evora comes stock with different wheel sizes:


From http://www.topspeed.com/cars/lotus/2010-lotus-evora-ar61199.html
Keeping a grip – 18 inch at the front, 19 inch at the rear.

Tyre choice is a vital component in the handling performance of every Lotus and for the Evora, Yokohama was chosen as development partner.

Lotus’s long-term relationship with Yokohama was swiftly rewarded during development when initially the front tyre size did not generate the Lotus required lateral grip, the Japanese grip gurus went away and developed bespoke tyres especially for the Evora – a 225/40 ZR18 at the front and larger diameter; 255/35 ZR19 at the rear. Both have carcass construction and a rubber compound unique to Lotus and are identified by the letters ‘LTS’ on the sidewalls.

P997S Jun 2, 2010 06:57 AM

many cars run staggered wheels

utkinpol Jun 2, 2010 08:15 AM


Originally Posted by P997S (Post 2860867)
many cars run staggered wheels

with all due respect 997 cars are not lotus evoras and 997 suspension was not designed to be used with rims of different sizes.

RF5BPilot Jun 2, 2010 08:24 AM

Consider taking your car to a DE day and have one (or more) of the senior instructors drive it and give you some feedback about the handling.

I'm not saying you can't do it yourself. But you have a degree of emotional involvement. An instructor with a lot of seat time would have a perspective that could help prepare you for handling characteristics at the extremes (which is where you will be in an unexpected corner someday or in accident avoidance). Better to get some information now than try to create that knowledge in the middle of a stressful situation. If you change tires later, have someone drive it again.

machina Jun 2, 2010 08:55 AM

i think it looks awesome, well done.

What suspension is on the car?

montreal997 Jun 2, 2010 10:18 AM

i think it looks trick. cheers!

ryem3 Jun 2, 2010 12:24 PM

With all due respect to some of the comments, the OP will love this info. TechArt's modded 2010 TT puts out like 600 hp or something, has PDK, and is riding on the same 19/20 front/rear wheel combination. They used a 235/315 combination though. For those that think this would generate too much understeer, the track time at Hockenheim was screaming and the 0-100kph time was 2.9 sec. Indeed 19/20 can work and work really well.

Sleepy996 Jun 2, 2010 12:40 PM

The wheels look awesome !

jon8 Jun 2, 2010 12:44 PM


Originally Posted by machina (Post 2860966)
i think it looks awesome, well done.

What suspension is on the car?

Bilstein damptronics.

i'm planning to change the rear end height though (a bit lower to reduce the gap)

i'm taking the car to a track this week-end, will keep you informed about the results.

1BlinkGone Jun 2, 2010 12:54 PM


Originally Posted by ryem3 (Post 2861236)
With all due respect to some of the comments, the OP will love this info. TechArt's modded 2010 TT puts out like 600 hp or something, has PDK, and is riding on the same 19/20 front/rear wheel combination. They used a 235/315 combination though. For those that think this would generate too much understeer, the track time at Hockenheim was screaming and the 0-100kph time was 2.9 sec. Indeed 19/20 can work and work really well.

+1. Staggered wheel sizes have been safely and successfully utilized for years.

jon8 Jun 2, 2010 01:33 PM


Originally Posted by wolfnards (Post 2860862)

Interesting. I thought the mismatching tires/wheels would be an issue, but found that the Lotus Evora comes stock with different wheel sizes:


From http://www.topspeed.com/cars/lotus/2010-lotus-evora-ar61199.html
Keeping a grip – 18 inch at the front, 19 inch at the rear.

Tyre choice is a vital component in the handling performance of every Lotus and for the Evora, Yokohama was chosen as development partner.

Lotus’s long-term relationship with Yokohama was swiftly rewarded during development when initially the front tyre size did not generate the Lotus required lateral grip, the Japanese grip gurus went away and developed bespoke tyres especially for the Evora – a 225/40 ZR18 at the front and larger diameter; 255/35 ZR19 at the rear. Both have carcass construction and a rubber compound unique to Lotus and are identified by the letters ‘LTS’ on the sidewalls.


No need to go as far as Lotus to see different wheels sizes on a same car.

Porsche Carrera GT:

265/35 ZR19 on 9,5J×19
335/30 ZR20 on 12,5J×20


What is really important is:

The overall wheel diameter (usually must be kept within 3%)

and

The weight of the wheel/tire combo

I see nothing else that could have an impact on how the car reacts (besides the tire's performance/properties of course)

jon8 Jun 4, 2010 04:48 PM

Hey guys, finally did my Jim Russel's driving course today :)

First of all: i can't recommend you enough to take that kind of lessons from qualified instructors; it's priceless what you'll learn in there (actually it's 400 bucks) but seriously just the toe n' heel thing is really somethin'. I have a f125 karting background so there is a lot of things that i knew already but i learned a lot of stuff that makes me a better driver now and also it makes the whole thing more fun and secure.

We were lucky enough (or badlucky depends of the point of view) to have a ''student'' that brought a brand new 2010 GT3 RS on the Mont-Tremblant (Canada) track today. Wow that's a car my friends.. At the end of the day when i was more comfortable with mine i tried to follow the GT3RS the best i could but, hey.. It's another league. The driver was good either.

My wheels/tires ? No problem whatsoever. Worked like a charm, with just the oversteer i wanted (was running all day with PSM ON just to be sure the Pirelli's won't explode if they knew it was Yoko's on front! haha just kidding) Seriously i pushed the car very hard today and the problem i encountered was really not the wheels or tires it was about the brakes. It's kind of hard on the brakes and i discovered that my brake fluid needs to be changed! The sudden spongy break pedal feel is not THAT funny when you go at 130mph... Anyway, that was a really nice day and i can't wait for the next track session.

Matt in Houston Jun 4, 2010 06:19 PM

So how did you like the turn in and steering feel with those front AD08's on the track?? Also, did you get your car aligned yet?


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