JGTC_350z

Hi guys ,

was over a discussion with a friend that he was saying that the front wheels of any car should always be wider than the rear to make it turn easier . is this right?

So what if the rear track is wider than the front..... assuming non-staggered setup ( 255/40/r18 +30 , wheel is 18x9.5 all around)

how will this affect the handling of the 350z , cause my front wheels sits flush but my rear is tucked in around 30mm , i thought of putting the H&R 25mm track spacers at the rear.

car is for autocross use.

thanks a lot

Motormouth

iTrader: (44)

that is not true for one, and second offsets are not the only thing that determine the track width. you would need to see what the car started out with f/r track width. the spindles could be spaced farther out further in the front, making even the same offset on the front and rear not make the track width even. and also, width of the rim and tire size affects this as well.

a wider front track makes the car (all things being equal) want to oversteer and a wider rear makes it want to understeer. so you can modify the track width to effect a change in the handling based on what you notice.

JGTC_350z

Motormouth: thanks a lot , so at least now i know my friend is BS'ing me =) .

would you guys run the H&R 25mm trak spacers for track usage?

z-u-later

iTrader: (43)

Your friend is an idiot . . . he probably has a FWD and does not realize the Z is a RWD.

z-u-later

iTrader: (43)

I use 25mm in front & 30mm in rear. I regularly autocross my Z, and occassionally have driven it on road courses with no spacer issues whatsoever.

scotts300

iTrader: (46)

A correct set-up will not need any spacers. You can run 17x10s at all 4-corners with 295FR and 315RR, 275FR and 275/295RR, etc., etc.

Motormouth

iTrader: (44)

well, he isn't B.S.ing you... it does matter, but no two cars are designed the same. if the platform has an inherent understeer problem, running a wider front track can help. so he is 'right' in some aspects.

again, widening a track is almost always a good thing, gives the car stability and increased lateral grip. it looks really cool too. but at the same time, it CAN mess up your balance. I don't know how much of a change it would take to actually notice a problem though. there are some real experienced guys here who might be able to point to some reference material for you though.

I can imagine if you kept the front at a 8.5 +30 and went to a 10.5 +20 rear you could have some issues with push and you can probably fix it in other ways (camber, tire sizes), but the cause for the change could have been the change in track width.

it is a very interesting question that you are posing and I bet some race alignment shops could help you out. maybe talk to whoever you are going to have do your alignments and tuning.

Motormouth

iTrader: (44)

I don't think he mentioned what offsets his rims are. he might not need to mess around with the offsets at all.

scotts300

iTrader: (46)

Very true. OP - offset is the #1 important factor in determining if wheels will fit and with what size tire. People overlook this fact all-too-often.