yes to both blue widebody s (thats why i get to tell you about "extreme offsets" )

with the wider track/offsets i had to use more effort to keep the car rolling straight when there were grooves in the road.

fwiw, im on UK alignment specs

 

I think the track width in the front has a big input on steering feel/sensitivity

I drove a non-stagerred on the ap1 rears and a 30mm spacer on the rear vs front with no spacer definitely a lot twitchier than 17x9 +45 x 4

 

I am days away from finishing my build and will be running 17x9.5 +22 on all four corners with 10mm spacers in the rear.

will the increased leverage have a negative/detramental effect on my suspension components?

 

I would be concerned with abnormal wheel/hub-bearing wear. To an extent, the stock wheel's centerline was engineered to be pretty close to the hub-bearing's centerline.

So if you push the wheels that far out, you might start to experience abnormal wear or failure around the outter edges of the bearing. It has to do with leverage... And if you track the car, the extreme forces will exacerbate the situation.

I'd just keep an eye (and ear) on things.

 

so it sounds to me, in a nutshell of what was said previously, that decreasing offset (and increasing scrub radius) increases feel and allows for higher cornering speeds. is there a point where one could lower offset too much and lower cornering performance (wear & tear weaknesses aside)?

 

That's a darn good question...

...in my original post, I actually had the Viper ARC in mind; talk about extreme widths!

From a pure theoretical standpoint, I don't see a downfall or drawback to making something wider and wider. It essentially furthers the center of gravity, which helps pivot the central mass of the object.......BUT I'm sure there's something I’m missing here...

Oh also, I've always heard that the Vipers are notoriously unstable during high speed cornering because of their short length compared to width...Maybe being too wide is possible.

 

Like the others pointed out, scrub radius and track width are proportional when changing offsets. Adjusting track width with offsets is a poor way of tuning.
From what I remember, the greatest benefit of track width is the reduction in ultimate lateral load transfer (moment arm about "front" cg increases). Hence why most race cars run wider tracks up front, helps keep the front laden tire form "tripping" over itself during corner entry. Yes, the S2000 has a wider track in the rear but remember that this is a vehicle for the general public, they love understeer.

 

Worth pointing out that changing offset changes scrub radius WAY WAY WAY more than it changes track width. Scrub radius is going to be on the order of millimeters, so even a modest 10mm change in offset is HUGE, probably more than double the scrub radius. Hence detectable changes in the feel of the car (not the same as increased performance potential). Track width is on the order of 1500mm, so a change in offset of 10mm => 20mm change in track is an increase of 1.0133, +1.33%.

I.e., with lower offsets you're changing scrub radius a LOT more than you're changing track width.

 

Let me give you guys something else to ponder. It's not on the s2k, but pertinent for this discussion. We have an LS1 powered RX7 racecar that we widened the rear fenders on to run 12" wide rears (335/30/18) to get maximum traction. The front we left stock with 10" rims on 295 tires. We tried everything to get the car to stop pushing. Softened the front springs, set rear toe to 0, front to 3/16 toe out, soft front swaybar. Front track was 4" narrower than the rear.

Finally we put a wider front nose on the car and switched to 315 tires on the same 12" rims. We then had to raise the front springs 250lbs and put back in the stiffer front bar to get rid of oversteer. The track is now .3" difference.

Now the tires going from 295 to 315 made a difference, but not that much. The track made a huge difference.

Also note that Spec Miatas now are allowed a bit wider track and all the front runners either changed their wheels or added spacers to take "advantage" of the rule. So they felt it made a difference.

Now I know the match says the difference is small, but for balance and maximum grip it does make a significant difference.

 

[QUOTE=blackey,Aug 8 2010, 07:35 AM]We have an LS1 powered RX7 racecar that we widened the rear fenders on to run 12" wide rears (335/30/18) to get maximum traction.