cant spin them up as quick.
As above, what are the major effects of having heavy big offset rims on your car,,,,,
I have my thoughts but want to hear from others.
Its not for a performance car,, street
heavy and big offset dont really go hand in hand though?
obviously a wider rim, in the same diameter from the same manufacturer, will be heavier.
i think the worst thing about deep rims, is just using them on the front. i think its wise to keep your front offset no deeper than single digits negative. ive gone beyond before, and the steering has a strange dead feeling. it is hard to describe. bump steer is said to be/theoretically is increased by a deeper offset too. obviously it is, but i didnt find it to be excessive when running 15x9 -13. the steering feel though is not so good.
also, on the front, it loads the already undersized wheel bearings excessively. i do hear of people front wheel bearings failing semi frequently.
wide rims do also limit the amount of lock you can get. there are other factors that effect/can counter act this, but still obviously, you need more room for bigger wheels.
still, apart from the aesthetics, i also do prefer the feel of a low profile tire stretched over a wide rim. i am quite aware it is not the ultimate solution for the fastest lap times/most grip. but thats not what i want out of my car. im simply want it to "feel" the way i want it to. sharp response, direct, twitchy.
there are other issues like un spring weight. but most decent quality deep rims arent actually all that heavy. at most around 7/8 kg. not super light, but not "heavy" either.
i used to have random mesh type wheels in 15" and then swapped all 4 for light weight 14" and the change in car handling was incredibly noticeable, and since experiencing that i have tried to keep light weight rims on most of the time, but tyres are another huge factor in car handling aswell
In my old 180 I was given some China 19's to slide on which were so heavy and first
run out with them I fried my clutch, the extra load was a killer,,,,
the other thing about wider rims is that it greatly effects your scrub radius.
which im led to belive when you hit bumps with the wheel it tends to "yank" the steering wheel as the wheel tends to pull around the strut rather than pulling through the castor arms. i think some ppl think this is bump steer, but its not as bump steer doesnt effect the steering wheel, bump steer is more the wheels changing angle on their own as they travel up and down.
hard to explain but its essentially creating a bigger "lever" for the bump to pull the wheel around on.
think of it as.....say you are holding a broomstick at about half way along...and your holding it horizontally and you get your mate to try and push the broom stick around you. then you hold it at the end and you get your mate to try again. youll notice its alot harder for you to hold the broom stick still.
in technical terms it creats a bigger moment about the king pin and thus has effects on your steering system. (moment = force by distance)
as can be seen in this pic it shows the scrub radius, and as the centre of your wheels move out (wider wheels crazy offset) the srub radius (the distance in the moment equation) becomes larger.
On a turbo car I work on, we notice the difference in acceleration (at traffic speeds) between having the 18" rims and the 15" rims. The 15" wheels give better acceleration at low and medium speeds (assuming there is grip). This is for two reasons. One is weight. The other is because the tyre diameter of the 18s is bigger.
all unsprung weight affects the performance of the vehicle.
it is not only more weight to accelerate and decelerate, but rotational forces are higher, and so harder to steer too.
light = free horsepower
my mk3 knock offs (b-bombs) are 15X7.5 and weigh in at 7.1kg a rim
my ssr mk3 15X8.5 weigh in at 6.8 kg.
just thought i'd start adding some wheel weights and hopefully others will put up other wheel weights (wata's, longchamps, and cheap knock off equivelents, rewinds etc)
so yeh the scrub radius will be increased by running the genuine mk3's but the extra track and lighter weight i think will be worth running the ssr's.
SLYDAR- did u lose any lock running 9's on the front? as its my understanding that anything bigger than an 8-8.5 will start to rub on full lock
stroked 2L ca18-ae86 in the build...eta xmas 2012?
Depends on their offset dude, fair few in Japan run 15x8.5 -6 on the front w 195/50, inner clearance is the same as an 8 +-0 which clear fine with p/s arms.
Ill weigh my 14x8 MK III's next time im changing tyres and see what they weigh.
RT142 Estate.
AJPS.