Wheels - How wide can you go?

[jet111]

Car AE86

Motor 20V 4AGE

Use Street & Track

Personal situation OK so I am at the stage in my build where I need to start looking for wheels... My question is how wide can you go on an AE86 without sacrificing the handling.

The biggest sizes I am considering are, Back: 15x9 -18 Front: 15x8.5 -12

This will increase by track by roughly 43mm back & 31mm front. I am currently running 7" -0

I am a bit worried that 8.5's on the front will ruin my handling a bit.. However I will be running pretty stretched tyres.

What is your experience running wide wheels? How wide can I go without wrecking my handling. I don't want to destroy the cars nimble cornering ability..

*edit* If I were to run wider wheels on the back than the front would this cause understeer?

[shift_rook]

increasing track will make the car twitchier, the question is pretty vague though, probably why no one else has answered it, as wide as you want to go, stretching tyres reduces gripby a bit so if you're looking at setting times i'd like at getting appropriately fitting tyres

[jet111]

That is fair enough.. I suppose I don't really know how to phrase my question. I don't know too much about wheels and how they change a cars characteristics.. so any help would be useful.

I wanted to make sure that 8.5's would not be too wide for the front of the car..

[blair]

Unfortunately its a "how long is a piece of string" question man, all your going to find is peoples opinions.

How serious are you going to get with your car? are you going to be trying to shave milliseconds off laptimes? or just go for a brap on the track for fun?

plenty of people run 8's/8.5's up front (me included) and it's definitely managable. Cars that actually drive hard aswel by the way.

[slydar]

the offset is more of an issue. the 86 suspension design already has a lot of scrub radius built into the design. -12 in my opinion is the absolute max neg offset you want on the front. less would be better. any less offset on the front though with an 8.5 in a 15 and you may be reducing the amount of lock you can get. make sure youre not using offset rcas with those big rims either. those things suck.

[jet111]

OK, thanks guys. That helps a lot. I will try and keep offset to a min.. It will either be -12 equip 03's or -7 SSR MK2's 15x8.5 on the front.

I will be using Greddy coilovers on their set height (I don't know how much lower that is than factory).... apparently this gives you 100mm *edit* of ground clearance... just. Other front mods include ALL new bushes (SuperPro), 25mm swaybar, Greddy Coilovers & T3 big lock steering arms with new tie rods & ends (factory replacements).

I am planning to use 40mm RCA's. Excuse my ignorance but what is an offset RCA?

I'm not going to try & set serious times with my car. I just want to have a bit of fun on the track but I do want it to handle really well. It will be mainly street driven. It will be a pretty hardcore street car, but that is the way I want it (it will not be my daily).. I don't want to destroy it by putting wheels on that are too big and will effect the car in a negative way.. Since I don't know much about suspension/wheels/steering I thought a couple of people might be able to point me in the right direction.. Is this making a bit more sense now?

Cheers,

Mark

[KurtHS]

10mm of ground clearance? 100mm?

You worried about making your car look badass or drive well and be comfortable and be legal?

[jet111]

ha... yeah, I meant 100mm. I'm trying to achieve the best of both worlds. It will NOT be comfortable... It will be legal, everything will be engineered. I'm trying not to go overboard with it, it will be very clean and built to a high standard, the wheels will be housed by steel flares. The looks will be a big part of it but I want it to drive well too, that is why I was concerned about wheel size & offset... Hence the reason for this thread

[LittleRedSpirit]

Slydar makes a good point about scrub radius. Most modern suspension systems, s13 for example, have the balljoint a bit further inside the tyre. The wheel pivots on a point more, whereas the older macpherson strut cars like ours kind of pivot like a compass. Sadly ugly high positive rims are better in this regard, but of course do not fit on an ae86 the way it is designed. I think the main limiting factor of ae86 struts, once you accept the design of the suspension, is the size of the stub axle and bearing. Wide wheels and big brakes on a car with ae86 struts means that in genearal your front wheel bearings will have a short life expectancy. Id be looking to go to a strut with a bigger stub axle such as xt130 which is more or less the best match for the car (dont use celica or st corona struts! Bad angles!) If it were to be a street car Id leave the greddy gear in Japan and just buy some excellent dampers and make coilovers out of some xt130 struts. The steel standard style system will be less interesting to the police and you could expect very strong as intended for road use.

The best you can do rims wise is to make sure whatever you buy is a safe but as close as possible distance from the strut on the inside. This way you counteract as much of the scrub radius as you can and it will steer as good as possible.

[jet111]

Perfect answer, thanks LittleRedSpirit