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Wider Rear Tyres?

Xizor
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Xizor Mentor

Xizor

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Hi guys,

As you may know from other threads i am looking to get some 18" starcorp Impuls rims with falken 451/2 tyres. Two people recently have brought up the fact i will have wider rear tyres and say this is not a good idea and will create alot of understeer.... where as i thought it would give me better grip? Especially with decent tyres...?

I know the rims arent the best quality, but its just a street car, not for racing. I dont see why they wouldnt be adequat as others on here have them and say they are ok.

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https://www.sau.com.au/forums/topic/123752-wider-rear-tyres/
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No Crust Racing Grand Master

No Crust Racing

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Posted

I have those wheels and wider rubber at the back (235 vs 265's). Understeer is only a problem if you have stock suspension and take a poor line into a corner. Skylines are a heavy car and don't like to dive into corners in the same fashion as a lighter car would, a smoother trajectory (more like slow in fast out) and better suspension will help. I have the height adjustable bilstiens from the group buy, they did wonders, now for some sway bars :rofl:.

scathing Grand Master

scathing

Posted
Posted
Well im not going to be a hero racing it on a track, so i think grip is more important than a little bit of understeer which shouldnt be too relevent for normal driving. Not like im gonna go thrashing around corners.

If you're not planning on being a hero on the track, understeer is a good thing. Understeer is safer than oversteer for a novice to middling driver, which is why practically every OEM tunes their cars to understeer when approaching the limit.

I noticed from your other threads that you're going for looks after some kind of major performance benefit, and cars with massive rear tyres always look hot. So don't worry about it. As long as your fronts aren't too narrow, in your case its not a major problem to have a wider rear.

I've gone from a staggered tyre size to the same all-round, but then I do like thrashing it around corners. :(

(and, as an aside, when my current street tyres wear out I'll be returning to a staggered size for the phat looks, yo)

NickR33 Grand Master

NickR33

Posted
Posted

I had noticed more understeer when I went to a staggered set of rims (8inch front 9inch rear) but this was only when pushing it very hard on motokhana style events with really tight corners (R33 GTSt's do understeer horrribly in these kind of events)... for everyday driving you won't notice it

BTW adjustable swaybars helped me tune out the understeer simply by tightening the rear a couple of notches... so I have the added grip in a straight line that wider tires will give plus its not pushing like a smack dealer anymore!

No Crust Racing Grand Master

No Crust Racing

Posted
Posted

I'm with Nick, R33's in general dislike tight corners where sudden changes of direction induces nose diving. This can be tuned out but it is far easier to deal with understeer as opposed to massive oversteer, which while fun, easily gets out of hand much faster. You can get super duper suspension setup and sway bars etc to deal with it, but you've said on numerous occassions that you want a compliant ride which means that your suspension mods will be a bit tamer and as such you'll get a little understeer. I came from a FWD car so it's natural for me to deal with, go have a trash late at night on a deserted section of road to get a feel for it if you're uncertain.

Also, in the time you've spent posting here and PM'ing me, you could've tested all this for yourself :( Just buy the damn wheels and post pics!

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