Tyre dilemma - multiple changes
06-30-2011, 11:06 PM
#31
UK Moderator
Thread Starter
I always run on track with the rear one click stiffer than the front. My understanding is that tends towards entry oversteer, and exit understeer, which translates to better turn in, and better rear grip and traction whilst putting the power down on exit. Always works for me.
The problem I had with Church (which is a long fast right hander) was in the middle of the corner, not the entry or the exit. Several times I had to make a big correction whilst the rear tried to overtake the front at 80 mph in the middle of the corner, and again my understanding (which may well be wrong) is that mid corner is nothing to do with the dampers. I had the same damper setup last time I was at Angelsey, but with RE050s and more rear toe. So it's either tyres or geo, and I don't believe it's tyres.
OTOH I used to suffer understeer on the hairpins (going in too fast I'm sure), and had none at all this time.
I think I'll go for a compromise setup next time and try something like 15' of rear toe. Having less toe does make the rear very controllable.
The problem I had with Church (which is a long fast right hander) was in the middle of the corner, not the entry or the exit. Several times I had to make a big correction whilst the rear tried to overtake the front at 80 mph in the middle of the corner, and again my understanding (which may well be wrong) is that mid corner is nothing to do with the dampers. I had the same damper setup last time I was at Angelsey, but with RE050s and more rear toe. So it's either tyres or geo, and I don't believe it's tyres.
OTOH I used to suffer understeer on the hairpins (going in too fast I'm sure), and had none at all this time.
I think I'll go for a compromise setup next time and try something like 15' of rear toe. Having less toe does make the rear very controllable.
But for just track day, just try to find one or 2 corners you wanna focus on and set it up right. If you get those right, the others normally won't be too bad either.
Certainly for Spa, I want the car well balanced and stable round high speed corners. The hairpins will take care of themselves - a spin at a hairpin is a lot less frightening than sideways through Blanchimont at 100mph!!!
07-01-2011, 12:48 AM
#32
Member
I think A048 are worth the extra over the R888 if you can, Simon. I've not had R888 on the S2000 but i've heard they don't last as long.
I'd also recommend a spare set of wheels. I will be sending mine to BaT so I can drive to tracks with less noise and also less wear. Those nasty european roads really wear out semi slicks with cambers on them. So think of it as health (hearing) / cost saving benefit.
Will be interesting to see your time difference with sticky tyres, as it will probably be the only change from last time and therefore any difference directly attributed to tyres?
This year my car is quite different to the last S, so should be quicker still in theory, plus i'm used to Spa so quicker there than most tracks. I'd not been to Anglesey before.
You might keep up with my Dad at Spa though
I'd also recommend a spare set of wheels. I will be sending mine to BaT so I can drive to tracks with less noise and also less wear. Those nasty european roads really wear out semi slicks with cambers on them. So think of it as health (hearing) / cost saving benefit.
Will be interesting to see your time difference with sticky tyres, as it will probably be the only change from last time and therefore any difference directly attributed to tyres?
This year my car is quite different to the last S, so should be quicker still in theory, plus i'm used to Spa so quicker there than most tracks. I'd not been to Anglesey before.
You might keep up with my Dad at Spa though
07-01-2011, 01:34 AM
#33
UK Moderator
Thread Starter
I think A048 are worth the extra over the R888 if you can, Simon. I've not had R888 on the S2000 but i've heard they don't last as long.
I'd also recommend a spare set of wheels. I will be sending mine to BaT so I can drive to tracks with less noise and also less wear. Those nasty european roads really wear out semi slicks with cambers on them. So think of it as health (hearing) / cost saving benefit.
Will be interesting to see your time difference with sticky tyres, as it will probably be the only change from last time and therefore any difference directly attributed to tyres?
This year my car is quite different to the last S, so should be quicker still in theory, plus i'm used to Spa so quicker there than most tracks. I'd not been to Anglesey before.
You might keep up with my Dad at Spa though
I'd also recommend a spare set of wheels. I will be sending mine to BaT so I can drive to tracks with less noise and also less wear. Those nasty european roads really wear out semi slicks with cambers on them. So think of it as health (hearing) / cost saving benefit.
Will be interesting to see your time difference with sticky tyres, as it will probably be the only change from last time and therefore any difference directly attributed to tyres?
This year my car is quite different to the last S, so should be quicker still in theory, plus i'm used to Spa so quicker there than most tracks. I'd not been to Anglesey before.
You might keep up with my Dad at Spa though
for them). Fitting and geo booked for the 16th.I've gone for 245/45 and 205/55 so should be lovely and stable. A048s are an expense too far - in fact the R888s are too really, so I'll hopefully revert to RE050as if/when they become available. If not, I'll have to enter the dark side of the 17" owners club for road use, and would probably go AD08. My stereo will easily drown out the noisy tyres.
I had the Gaz shocks at Spa last year and the Billies are on for this year, as well as some bracing and weight adding sound deadening - If I take the spare out this year, that should even things out.
07-01-2011, 06:44 AM
#34
With R888 have you a baffled sump?
IIRC Raz posted something about the suspension mounts being a little weak and need reinforcement with prolonged use of stick tyres..
IIRC Raz posted something about the suspension mounts being a little weak and need reinforcement with prolonged use of stick tyres..
07-01-2011, 07:13 AM
#36
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I have found a very good post that is pretty good for you to read, pretty much same thing I learnt from my race engineering dip course -
http://forums.rennlist.com/rennforum...l-setup-2.html
This graph below will make you easier to understand what the suspension damping is doing, the graph is talking about tyres slip angle but can also use this to explain suspension damping - Just imagine the number on the top lines is the damper setting. Damping graph is very similar to this graph.
On the Yellow line = on the soft setting, green is the optimum setting and purple is the stiff setting. What I normally do is set it to below medium soft and push 2 click up until the car start under or over, then you wind back 2 click down. Thats how I find my optimum setup, under damping and over damping will both lose time and grip.
Try this out and you should able to get more from your suspension easier, if you have a 2 ways suspension and easy way to understand is Bounce is for initial turn in, Rebounce is for corner exit, theory behind the setup is the same.
http://forums.rennlist.com/rennforum...l-setup-2.html
This graph below will make you easier to understand what the suspension damping is doing, the graph is talking about tyres slip angle but can also use this to explain suspension damping - Just imagine the number on the top lines is the damper setting. Damping graph is very similar to this graph.
On the Yellow line = on the soft setting, green is the optimum setting and purple is the stiff setting. What I normally do is set it to below medium soft and push 2 click up until the car start under or over, then you wind back 2 click down. Thats how I find my optimum setup, under damping and over damping will both lose time and grip.
Try this out and you should able to get more from your suspension easier, if you have a 2 ways suspension and easy way to understand is Bounce is for initial turn in, Rebounce is for corner exit, theory behind the setup is the same.
07-01-2011, 07:32 AM
#37
UK Moderator
Thread Starter
Thanks Dixon - The Bilsteins only have 9 clicks, so maybe only 1 click adjustment, rather than two?
The car was great at Cadwell on 2 front and 2 rear, I struggled a bit at Anglesey, but that may have been down to tyres, or the different ircuit, or just me having a bit of an off-day.
I was able to do some experimenting at Rockingham last year (on the Gaz shocks, not the Bilsteins) which was quite interesting too.
https://www.s2ki.com/s2000/topic/798...t__p__19506431
The car was great at Cadwell on 2 front and 2 rear, I struggled a bit at Anglesey, but that may have been down to tyres, or the different ircuit, or just me having a bit of an off-day.
I was able to do some experimenting at Rockingham last year (on the Gaz shocks, not the Bilsteins) which was quite interesting too.
https://www.s2ki.com/s2000/topic/798...t__p__19506431
07-01-2011, 07:46 AM
#38
Member
Simon, i'd be a little wary of high g corners like Puhon without a baffled sump. I think the oil pickup might be on the right side for that corner, but the issue cn be oil returning back to the sump.
PS - might only be a few trackdays but it's not a long term degradation issue with oil starvation, it's pretty quick / instant. Not saying it will be an issue, but just to bear in mind.
PS - might only be a few trackdays but it's not a long term degradation issue with oil starvation, it's pretty quick / instant. Not saying it will be an issue, but just to bear in mind.
07-01-2011, 08:02 AM
#40
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Thanks Dixon - The Bilsteins only have 9 clicks, so maybe only 1 click adjustment, rather than two?
The car was great at Cadwell on 2 front and 2 rear, I struggled a bit at Anglesey, but that may have been down to tyres, or the different ircuit, or just me having a bit of an off-day.
I was able to do some experimenting at Rockingham last year (on the Gaz shocks, not the Bilsteins) which was quite interesting too.
https://www.s2ki.com/s2000/topic/798...t__p__19506431
The car was great at Cadwell on 2 front and 2 rear, I struggled a bit at Anglesey, but that may have been down to tyres, or the different ircuit, or just me having a bit of an off-day.
I was able to do some experimenting at Rockingham last year (on the Gaz shocks, not the Bilsteins) which was quite interesting too.
https://www.s2ki.com/s2000/topic/798...t__p__19506431
If your 2 ways or just 1 way for both bump and rebounce?
Tyre is one of the most important thing, as it is the only thing that contact the road. It doesn't matter what fancy bits you have on the car, if you have crap tyres you are not going anywhere.