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FD3S 50/50 distribution + larger rear tires?

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Old 12-11-07, 02:56 PM
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FD3S 50/50 distribution + larger rear tires?

Hey guys,




I have being offered a free set of 17x8.5/17x9.5 A-tech Final speed forged dark bronze wheels for my FD... They are really nice, are concaved and only 16lbs aparently.



My question is what will 255 rears/ 235 fronts do to the perfect balancing of the FD? Should i run 245/245?



I just want to make sure that im not going to mess with my awesome handling with these wheels.




Thanks,


=Ben
Old 12-11-07, 03:11 PM
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50/50 doesn't equal great handling. The Lotus Elise is about 30/70 yet you don't see those guys (and gals) complaining about handling.

The more you increase tire sizes in the rear verses the front, the more understeer you will create. Now for some, this is desirable as the FD is naturally a little oversteery.

Unless you are really pushing the car hard on a road course, I doubt you will notice much difference. Even then, it can be handled with some adjustability in the suspension components.
Old 12-11-07, 03:43 PM
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Hmm, this is what i experianced with my s5 turbo.. 235 rear and 215 front. In the wet it would understeer a lot.


personally i would rather have a little bit more oversteer than understeer. So if i run 245 all the way around would this be achived?


Thanks Mahjik,



=Ben
Old 12-11-07, 04:30 PM
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Originally Posted by Mahjik
50/50 doesn't equal great handling. The Lotus Elise is about 30/70 yet you don't see those guys (and gals) complaining about handling.

The more you increase tire sizes in the rear verses the front, the more understeer you will create. Now for some, this is desirable as the FD is naturally a little oversteery.

Unless you are really pushing the car hard on a road course, I doubt you will notice much difference. Even then, it can be handled with some adjustability in the suspension components.

Well....I feel very confident in stating a 50/50 weight distribution is a GREAT platform to build a high performance sports/race car. Tuning the suspension is specific to power, track configuration(s), conditions and driver style. I personally run 255 40 17's at all four corners and find the 7 very well balanced.
Old 12-11-07, 04:37 PM
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Originally Posted by Jack
Well....I feel very confident in stating a 50/50 weight distribution is a GREAT platform to build a high performance sports/race car.
If that were for building true mid-engine car, then I'd agree with you.

However cars not being 50/50 have never stopped them from being incredible cars. Most of the cars seen today as 'best handling' are far from 50/50. IMO, there is more to a car's handling than just where it's weight is or isn't.
Old 12-11-07, 04:37 PM
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Originally Posted by apexFD
So if i run 245 all the way around would this be achived?
That would be a more neutral setup.
Old 12-11-07, 06:46 PM
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Originally Posted by Mahjik
If that were for building true mid-engine car, then I'd agree with you.

However cars not being 50/50 have never stopped them from being incredible cars. Most of the cars seen today as 'best handling' are far from 50/50. IMO, there is more to a car's handling than just where it's weight is or isn't.

Thats true, however the suspension, has to be designed to offset the imbalanced platform. The older 911's were the best example, if you went into a corner to hot and lifted, you were in a heap of trouble. With a 7, that situation is much easier to negoiate due to the front mid engine design and 50/50 weight distribution.
Old 12-12-07, 02:29 AM
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An old 911 is about the most extreme case you could pick to try and make your case. Not to start an arguement, but as said before, there is a hell of a lot more to a cars handling characteristics than just weight distribution. Is 50/50 bad.. no. Is it the "best", not necessarily.

But to answer the OPs question, it depends on your driving style and suspension setup, but you shouldnt see any ill issues when running a slight stagger with rear bias. Most guys run this setup on the street, as wider fronts tend to follow road imperfections more, making the car feel "darty", and extra rear traction helps keep the car managable from not so easily overpowering.
Old 12-12-07, 03:10 AM
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What's the offsets on the wheels?

ditto what's said above:

DRiving style, experience

Power of vehicle.... Type of turbo?

Rishie
Old 12-12-07, 09:14 AM
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if the offsets are good you can run a 255 all around with an effectively wider footprint out back because of the wider wheel.

245 or 255 all around, whatever works out best for tire diameter too, that plays a role in gearing and such...
Old 12-12-07, 11:29 AM
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Well i am not 100% sure on offset.

But the rims are more or less flush with the fenders.


My car will be 280-300rwhp when im done my build (stock twins), and my drive train and gearing is also stock.


I just want the handling to remain neutral.


However i am having a hard time to decide on what kind of suspension setup i want to have... I was planning on keeping stock until i figured it out. I dont want anything rediculously stiff, however i dont want mad body roll.


What about camber on the wheeels? How should this be adjusted?





=Ben
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