End of the square vs staggered
10-15-2018, 04:24 AM
#111
I've been reading this thread with interest as I switched from 225/255 to 255 square last year and had the same experience as bgoetz. I'm faster than before (hard to quantify as I'm also improving as a driver) but the differences are much more in the qualitative department such as comfort approaching the limit, getting back when over the limit, braking at the limit, etc.
For many of us, the square vs. staggered phrase translates to upgrading the fronts from 225 to 255. And in that context, I agree with bgoetz that there is no more discussion needed - certainly not for me either. Square is the way to go. But if there are no limits on tire width, then I'm not sure this is a debate that can lead to an agreeable outcome. There are so many additional variables as ZDan pointed out..
For many of us, the square vs. staggered phrase translates to upgrading the fronts from 225 to 255. And in that context, I agree with bgoetz that there is no more discussion needed - certainly not for me either. Square is the way to go. But if there are no limits on tire width, then I'm not sure this is a debate that can lead to an agreeable outcome. There are so many additional variables as ZDan pointed out..
10-15-2018, 01:52 PM
#112
When you guys made the switch from 225/255 to 255 square, did you guys also make accommodations for roll center adjustent/offset upper arm joints, sway bars and/or springs? I find it hard to believe -from personal experience- that without these accompanying adjustments a square wheel/tire setup would be a) faster and b) easier to approach, come back from and dance on the limit.
10-15-2018, 02:51 PM
#113
It's kinda hard cause when most people go square, the tire width isn't the only thing they change. But I am a square believer. Wouldn't go back. car listens now.
All I did was max out camber in the front and added rear.
I'm just spitballing here but what about going square by taking tire away in the rear, same thing basically right? square doesn't require as much steering angle which Is the greatest help? 245/255 could be better since feedback, tire plants faster,
All I did was max out camber in the front and added rear.
I'm just spitballing here but what about going square by taking tire away in the rear, same thing basically right? square doesn't require as much steering angle which Is the greatest help? 245/255 could be better since feedback, tire plants faster,
Last edited by starchland; 10-15-2018 at 02:59 PM.
10-15-2018, 03:13 PM
#114
When you guys made the switch from 225/255 to 255 square, did you guys also make accommodations for roll center adjustent/offset upper arm joints, sway bars and/or springs? I find it hard to believe -from personal experience- that without these accompanying adjustments a square wheel/tire setup would be a) faster and b) easier to approach, come back from and dance on the limit.
As for changing springs and roll bars, in my case, I went to square in three steps:
- Added offset camber ball joints up front to get to 3+ deg camber. The kit came with roll center adjusters but I did not install them as i was not lowering the suspension. I ran that with stock MY00 suspension for almost 2 years with AP2V2 wheels and 225/255 tires.
- Installed SBG version of Ohlins with 10k/10k springs and left roll bars stock. I also added the roll center spacers up front. Ride heights are 339/339mm.
- Switched to 255 square on 17x9 wheels for track.
In my case, the improvements going to 255 square made the car more fun to drive at the limit, but the fundamental balance of the car under various conditions did not significantly change. Rather, when the car would have understeered in the past, now it did so less. When the car would have oversteered in the past, now it might do so a little sooner with square setup, but in both cases, the oversteer was expected and not surprising - hence manageable. There is a lot of misinformation that suggests the S2000 will be an uncontrollable oversteering disaster if you go square and don't stagger springs or add a larger front roll bar. My own experience says that's just not the case.
It is important for the driver to understand weight transfer and how that affects a rear wheel drive car. And it is important to spend time adjusting the shocks, camber, and ride height and get seat time to become comfortable with it. But you need to do those things regardless if you're running staggered or square. If you had set the car up to be generally loose with a staggered setup, then you might want to increase front spring rate or bar, or add some rear camber. But I don't think you'd find you would need to make significant changes going from staggered to square, at least when tires are limited to 255. I haven't gone wider so leave that to others to comment on.
EDIT: one more thing that I think might make a difference is how aggressive the setup is for the track. In my case the car is also street driven a lot so I didn't go that stiff with the springs and ride height. I could imagine that stiffer springs along with a lower ride height might A) be able to take more advantage of the wider front tires, and B) might require more adjustments to compensate for the wider front tires. But that's just a guess.
Last edited by DanielB; 10-15-2018 at 03:17 PM.
10-16-2018, 08:10 PM
#115
I think roll center spacers would only matter if you are changing the ride height - and I don't see why going square would require changes in ride height unless you choose wheels that don't fit under the fenders - and there are choices that do fit.
As for changing springs and roll bars, in my case, I went to square in three steps:
In my case, the improvements going to 255 square made the car more fun to drive at the limit, but the fundamental balance of the car under various conditions did not significantly change. Rather, when the car would have understeered in the past, now it did so less. When the car would have oversteered in the past, now it might do so a little sooner with square setup, but in both cases, the oversteer was expected and not surprising - hence manageable. There is a lot of misinformation that suggests the S2000 will be an uncontrollable oversteering disaster if you go square and don't stagger springs or add a larger front roll bar. My own experience says that's just not the case.
It is important for the driver to understand weight transfer and how that affects a rear wheel drive car. And it is important to spend time adjusting the shocks, camber, and ride height and get seat time to become comfortable with it. But you need to do those things regardless if you're running staggered or square. If you had set the car up to be generally loose with a staggered setup, then you might want to increase front spring rate or bar, or add some rear camber. But I don't think you'd find you would need to make significant changes going from staggered to square, at least when tires are limited to 255. I haven't gone wider so leave that to others to comment on.
EDIT: one more thing that I think might make a difference is how aggressive the setup is for the track. In my case the car is also street driven a lot so I didn't go that stiff with the springs and ride height. I could imagine that stiffer springs along with a lower ride height might A) be able to take more advantage of the wider front tires, and B) might require more adjustments to compensate for the wider front tires. But that's just a guess.
As for changing springs and roll bars, in my case, I went to square in three steps:
- Added offset camber ball joints up front to get to 3+ deg camber. The kit came with roll center adjusters but I did not install them as i was not lowering the suspension. I ran that with stock MY00 suspension for almost 2 years with AP2V2 wheels and 225/255 tires.
- Installed SBG version of Ohlins with 10k/10k springs and left roll bars stock. I also added the roll center spacers up front. Ride heights are 339/339mm.
- Switched to 255 square on 17x9 wheels for track.
In my case, the improvements going to 255 square made the car more fun to drive at the limit, but the fundamental balance of the car under various conditions did not significantly change. Rather, when the car would have understeered in the past, now it did so less. When the car would have oversteered in the past, now it might do so a little sooner with square setup, but in both cases, the oversteer was expected and not surprising - hence manageable. There is a lot of misinformation that suggests the S2000 will be an uncontrollable oversteering disaster if you go square and don't stagger springs or add a larger front roll bar. My own experience says that's just not the case.
It is important for the driver to understand weight transfer and how that affects a rear wheel drive car. And it is important to spend time adjusting the shocks, camber, and ride height and get seat time to become comfortable with it. But you need to do those things regardless if you're running staggered or square. If you had set the car up to be generally loose with a staggered setup, then you might want to increase front spring rate or bar, or add some rear camber. But I don't think you'd find you would need to make significant changes going from staggered to square, at least when tires are limited to 255. I haven't gone wider so leave that to others to comment on.
EDIT: one more thing that I think might make a difference is how aggressive the setup is for the track. In my case the car is also street driven a lot so I didn't go that stiff with the springs and ride height. I could imagine that stiffer springs along with a lower ride height might A) be able to take more advantage of the wider front tires, and B) might require more adjustments to compensate for the wider front tires. But that's just a guess.
Your initial experience and expectations were in line with my own. I expected over-steer and losing-the-rear on corner entry under hard braking, but as you mentioned, it seems to be that "the basic handling characteristics remained unchanged." I look forward to getting more seat time in so I can further confirm your assessment. So far it feels just like it did before, but now with more responsive steering and grip.
Can you elaborate on how stiffer springs would take advantage of grip? I'm considering moving to a 10/10k or 12/12k setup, if that will improve grip and overall balance/predictability. I have my car setup for the streets since I use it as a weekend canyon driver.
10-18-2018, 11:31 AM
#116
Reflecting on this thread, the answer seems clear: run the biggest tires you can given the limitations you may face:
- Class rules restricting tire selection (e.g. specified sizes, wear ratings, tread depth, specific models, etc.) For example Solo II STR has 255 max spec cross section, NASA TT5 has 266mm measured cross section, Solo II Street requires TW200 with that ship with 7/32nds tread)
- What fits under the fenders, or can be made to fit under the fenders. For example, 255 fronts in Solo II require lots of negative camber. 295+ fronts would require some significant fender replacement or modification.
- What the chassis can compensate for. A much taller tire may require lowering that significantly harms the suspension geometry.
- What will work with the chassis. Balancing a huge rear tire may cause the inside rear to lift, rendering the OEM Torsen diff inoperative.
- What is still within the range of available parts to balance the chassis.
- The tire is available in a make/model capable of meeting performance objectives: capable of winning, of driving to the track, etc.
10-31-2018, 11:42 AM
#117
Former Sponsor
You might need to do it a 3rd time, because apparently its not that clear. I think there probably are some diminishing returns on tire width, but 255 is not it with this car, and since that's all you can reasonably squeeze up front, logic says limiting yourself to a 255 in the rear of the car to run "square" isn't the all out best performing option. We are talking unlimited set up here. Serves no point in talking what's best within a certain sanctioned rule based class, which some people tend to forget. I don't care what works best within a class. I look at how to maximize the performance threshold of the car period.
In an autocross setting (ignoring that STR class limits you to a 255) where your runs are short, yes, perhaps 255 is where you want to be since you may not be able to bring such a wide tire up to temp quickly.
11-04-2018, 02:15 PM
#118
After finally squaring away my square wheel/tire issue I can now confirm the OP's sentiment: square is better in every possible way. The only thing I miss about a staggered wheel/tire setup is the on-center steering feel. Going square on this car should be considered a religion, or at the very least a cult 
11-05-2018, 06:23 PM
#120
Maybe we should hold our horses on that one. Has anyone made the rear tire smaller to go square? I've only heard of one case where that was done. It was a B/Street autocross car and the rear was reduced to 245 from 255. However, that class doesn't allow any ride height adjustment to compensate for the taller 255. And the size difference is minimal.
Would a car 255 front and 275 rear go faster as 255 square even with a free choice of springs, anti-roll bars, and ride height?
Would a car 255 front and 275 rear go faster as 255 square even with a free choice of springs, anti-roll bars, and ride height?