Nankang 245's fitted
???
Who knows what's going on. DSC doesn't know what brand of tyre you are using though, so why should it matter?
Maybe you do get what you pay for and Hymee and I are just lucky....
Or perhaps DSC cuts in more for some people than others because of different driving technique.
Who knows what's going on. DSC doesn't know what brand of tyre you are using though, so why should it matter?
Maybe you do get what you pay for and Hymee and I are just lucky....
Or perhaps DSC cuts in more for some people than others because of different driving technique.
If your fronts are 3 months from being replaced then they are anywhere from 4-6mm lower than the nankangs you put on the back. Also, did you mention if they were the same profile and width? becacuse as has been mentioned in this thread, staggered doesnt work well.
You could try something.....Put the rears at the front and fronts at the rear. See if it kicks in still.
Andrew
You could try something.....Put the rears at the front and fronts at the rear. See if it kicks in still.
Andrew
with two tyres with different grip potentials you can change the handling significantly.
I'd guess the re40's on the front have more grip, making it more likely to oversteer and hence make the DSC kick in.
have a look at this link to diagnose under-oversteer characteristics.
http://rogerkrausracing.com/overundr.html
I'd guess the re40's on the front have more grip, making it more likely to oversteer and hence make the DSC kick in.
have a look at this link to diagnose under-oversteer characteristics.
http://rogerkrausracing.com/overundr.html
Everything else being equal, a staggered set-up on a car as neutral as the 8 would tend to accentuate any understeering handling tendencies, ie, approximately neutral grip on all four tyres altered by a larger rear tread area, shifting grip rearwards. Of course, if you increase power output (ie, through FI), then you might want to increase rear grip to compensate for the easier loss of traction at the rear due to higher output. It's always an interesting game 
As to DSC curring in, reading back, I think auzoom has hit it above. It seems to me that in all cases where DCS is causing problems, it is because of a staggered set-up created by fitting new oversize rears with worn OEM fronts, eg, new Nankang (or other) 245/40 rear with worn B/S 225/45 040's on the front. As Andrew points out, the additional wear on the OEMs probably reduces their rolling circumference well out of the DSC's calibration, hence the problem.
Solution? Well, unless you have or are getting a major power upgrade, stick to the same sized tyre all round for best handling results and no DSC crazies. If you are going to do a staggered set-up, then you need to give close attention to a set-up where there is minimal difference in the rolling circumference between the front and rear tyres. But don't be surprised if the car doesn't handle as well

As to DSC curring in, reading back, I think auzoom has hit it above. It seems to me that in all cases where DCS is causing problems, it is because of a staggered set-up created by fitting new oversize rears with worn OEM fronts, eg, new Nankang (or other) 245/40 rear with worn B/S 225/45 040's on the front. As Andrew points out, the additional wear on the OEMs probably reduces their rolling circumference well out of the DSC's calibration, hence the problem.
Solution? Well, unless you have or are getting a major power upgrade, stick to the same sized tyre all round for best handling results and no DSC crazies. If you are going to do a staggered set-up, then you need to give close attention to a set-up where there is minimal difference in the rolling circumference between the front and rear tyres. But don't be surprised if the car doesn't handle as well
Originally Posted by rotarenvy
the staggered theory assumes the nankangs have grip :P
but to be fair, I haven't heard anyone with a full, new set of Nankangs complain about grip issues
that's because when the front is the same as the rear you don't notice, since girp is the same front and rear. If the staggered setup had more grip because of the width (and the nankings) the car would push in the turns and DSC wouldn't be noticed as much.
Hymee, from what I can tell its the DSC kicking in, ie the ECU is applying braking to a particular wheel which it thinks is spinning/has to much power going to it.
Only the people with the Nankangs can say if there is grip or not, but in this day and age, I cant imagine a tyre available that wouldn't be safe for daily driving. Tracking is another issue.
Only the people with the Nankangs can say if there is grip or not, but in this day and age, I cant imagine a tyre available that wouldn't be safe for daily driving. Tracking is another issue.
Thanks. Different to what I experienced when the ABS/DSC system was fed a real wheel signal to the front sensors. Different number of teeth - so I was thinking donw the different diameter path. Obviously thinking out too loudly. 
Cheers,
Hymee.

Cheers,
Hymee.
Originally Posted by Hymee
Obviously thinking out too loudly. 

Seriously, I am lost on what you are saying because I would have thought it was the same results. As the front wheels are now (in rolling diameter terms) a reasonable amount smaller than the new rear wheel, the front sensor is turning faster than the rear one...in this instance, faster than normal.
Originally Posted by auzoom
You know you have a very loud brain!
Seriously, I am lost on what you are saying because I would have thought it was the same results. As the front wheels are now (in rolling diameter terms) a reasonable amount smaller than the new rear wheel, the front sensor is turning faster than the rear one...in this instance, faster than normal.
Seriously, I am lost on what you are saying because I would have thought it was the same results. As the front wheels are now (in rolling diameter terms) a reasonable amount smaller than the new rear wheel, the front sensor is turning faster than the rear one...in this instance, faster than normal.
One of the things involved disconnecting the sensors. This threw an error condition with DSC/TC lights displayed. The car drove OK, just no ABS or TC/DSC happening.
Another experiment was to feed the signal from the rear wheels to the front, in attempt to fool the ABS system to think the front and rear wheels were going at the same speeds. This did not cause the DSC to "kick-in" but still caused the same error condition. From memory, all was OK until you drove around a corner. But the car was still perfectly driveable, and we even tried it out on the dyno.
So that is why I asked the questions. My experiences have not been "DSC kicking in", but rather the DSC lights coming on to indicate an error condition.
Does that help to explain? Yes - One would think the results would be the same, but like I said, I had no DSC interfering with my driving like the others report.
Cheers,
Hymee.
Last edited by Hymee; Apr 30, 2006 at 03:59 PM.
Originally Posted by rotarenvy
the staggered theory assumes the nankangs have grip :P
I don't know. I was reaching 160km/h by the end of the straight. From what I heard guys like Choppy were getting the same speed NA. The SC was far from its final tune.
I'm not trying to defend the Nankangs and say that they are the best tyres on the market. After all, you have to get what you pay for to some extent. But just because they are cheap does not automatically make them ****. If it weren't for this thread I would not have a bad thing to say about them. I'm happy with 90% of the performance for 50% of the price.
I'm not trying to defend the Nankangs and say that they are the best tyres on the market. After all, you have to get what you pay for to some extent. But just because they are cheap does not automatically make them ****. If it weren't for this thread I would not have a bad thing to say about them. I'm happy with 90% of the performance for 50% of the price.
Originally Posted by Hymee
As for grip, I just checked wifies Nankangs, and the traction rating was "A" whereas the Yoko's are "AA". But on the flip side, the Nankangs are a "240" wear rating, and the Yoko's are "180".
FYI, there's not much difference between "A" and "AA"
From the Uniform Tire Quality Grade (UTQG) labeling system:
Straight-a-head wet braking traction has been represented by a grade of A, B, or C with A being the highest. In 1997 a new top rating of "AA" has been introduced to indicate even greater wet braking traction. However, due to its newness, this grade will probably be applied initially to new tire lines as they are introduced and later to existing lines which excel in wet braking, but had been limited to the previous top grade of "A". Traction grades do not indicate wet cornering ability.


