Gernby

iTrader: (1)

While searching around TIS, I found some suspension diagrams that show the .5" difference in ride height on the sport model is totally due to a different front knuckle, and the rear ride height is NOT lower. Does anyone know if this is the ONLY suspension difference? I read in another thread (that I can't find now) that said the springs have the same rate. If that is true, then I'm guessing the springs are totally identical, and the shocks probably are as well. Has anyone measured the thickness of the stock and / or sport sway bars?

al503

I could see the spring rates being the same but there is a noticeable difference in damping. I think the shocks are set stiffer in the sport models.

ff_

According to the IS brochure, the SP has a "sport-tuned suspension". Doesn't mean that it's any different than the base suspension though. Wouldn't be the first time that a carmaker puts together a sport package that didn't include anything that improves perfomance...

al503

From what I could tell with my test drives, there is a definite difference in ride. Something or some things is/are different.

Gernby

iTrader: (1)

Actually, after looking at the diagram again, it may be possible that the rear suspension height is different, but I don't think it is. The rear toe and camber specs are the same for both models.

ihkskim

when i initially went car shopping, they told me the shocks were bilsteins in the SP. unless he lied

sincityIS

Not to critisize, but isn't this an enthusiast forum? Shouldn't someone know the answer to this?

lobuxracer

iTrader: (2)

Gernby - where did you find info on the sport set up? New Car Features? There should be a complete table for the differences in that document, or at least, typically there is something in the NCF describing all the differences.

Gernby

iTrader: (1)

I haven't finished looking through TIS. Where I found the difference in the Knucks is in the Front Alignment document. It specifies 111 mm between the bottom of the knuckle and the center of the wheel (A-B) for the "normal" 2IS, and 121 mm for the same on the "Sport" 2IS.

Toyota_F1

iTrader: (1)

Still checking on ride height but the difference is

Front End Alignment - Camber, Caster, King Pin Inclination - All Different on sport package

Rear End Alignment - Same for all IS with 18" wheel setup

lobuxracer

iTrader: (2)

The knuckle is identical. The ride height is 10mm lower, that's why the difference. You could do that with just springs.

Also, there are no distinctions between sport and "normal" when measuring the upper and lower wishbones. I suspect the increase in camber is just ordinary camber gain from a 10mm drop. It's still nothing for camber, not even 0.5 degrees on either setup. I'll be surprised if I don't wear out the outer blocks on these tires first. I usually need at least -1.0 degree to keep from shredding the outer blocks even on the street.

Oh, now I see where you are not getting the whole picture. B is the height of the inboard pivot bolt for the control arm, not the height of the knuckle. Those relative heights will never change. The height of the inboard pivot bolt has always been the Toyco standard for measurement. In years gone by they'd specify ride height relative to the ground, but this doesn't work well since tire tread wear affects the absolute height of the pivot bolt too. So now they have you measure to ground from the center of the wheel and subtract the height of the inboard pivot bolt to account for tire wear and remove it as a variable.

Gernby

iTrader: (1)

Lance,

Did you look at the PDF I referenced? The measurement I am talking about has nothing to do with springs. Measurement A is the distance from the ground to the spindle's center, and measurement B is the distance from the ground to the bottom of the knuckle. Both of these are equally effected by the outer diameter of the tire. However, the height specification in the alignment document for the front is the DIFFERENCE between the two (A-B) which does not have anything to do with spring length or outer tire diameter. Unless the document is very poorly written, A-B is the distance from the bottom of the Knuckle to the center of the spindle, which is 10 mm more for the Sport edition. Basically, the Sport suspension places the center of the front wheel 10 mm higher above the lower control arm than the non-sport suspension.

lobuxracer

iTrader: (2)

Yes. I have the PDF. No, the measurement is not to the ball joint. Look on page 2, it gives a description of measurement B. A measurement from the center of the wheel to any point near the ball joint will never change unless there is severe damage to the suspension upright.

Look at page 5 of the 03600210.pdf. At the top of the page, you'll see the two bolts used for measuring the ride height in the first illustration C106396, step 7. The measurement is not from the ball joint (knuckle).

Gernby

iTrader: (1)

This is from the TIS front alignment document. It doesn't mention anything about ball joints, but I don't think I did either. What it does mention for both is that it is gound clearance (unsprung). Looking at the diagram (which I can't post without violating copyright laws), I don't see how the difference between A and B could be anything other than a dimension of the knuckle (10 mm from normal and sport).

I don't know what 03600210 or C106396 is since I saved the PDF files by their functional titles...

Gernby

iTrader: (1)

Wait a minute ... Are you saying that measurement B is from the ground to a bolt on the chassis? If that is the case, then the front alignment drawing is total crap!