Periodoc

My 07 S2K has a little over 60K miles and I want to refresh the suspension, as well as do some occasional HPDE. I'm getting the brakes squared away and am thinking of a 245 square setup using bored out rear wheels, Club Racer dampers, Spec R springs and Club racer swaybars. What would the handling characteristics be? Push, Neutral, Oversteer? Thanks

gptoyz

CR suspension is great for a no fuss, idiot proof damper

As for the sway bars, leave the rear on the stock AP2, you want less bar to give the rear better traction since you are upping the size of the front tires. In fact, leave the front sway bar stock, too. While the front AP2, isn't as stiff as the CR bar, it's not such a drastic difference as to justify changing it. What you can do is switch to a poly sway bar bushing front and rear, this will allow the sway bars to respond quicker and behave like a stiffer bar as the poly won't deform like the rubber bushing.

If you haven't already changed out the engine mounts and diff mounts, I would go with the Megan Hard Race or Spoon solid rubber engine and diff mounts as this will also increase the response of your car.

Chuck S

Going from 215 to 245 front tires will induce oversteer. Requires buggering the car body work too. Where are you placing in the local AutoX events? Tires? Alignment? Note the CR suspension retained the front tire size and widened the rear to 255 for the opposite effect.

Taken a performance driving course? Self taught fast driving skills are often full of bad habits that just keep getting repeated. I'll not start second guessing the Honda engineers until I know I'm getting all the performance out of the car as designed and I know I ain't even close. (OK, OK, I have 255mm rears! )

-- Chuck

freq

Save all that money and run it stock for the first year or two.

Seat time, seat time, seat time. Unless of course you're a track veteran and didn't state that.

Car Analogy

As you already realize, you're switch to square shifts the bias rearward, and the cr components would shift it back forward. The question of course is by how much does each of these changes shift things, and where the final balance lies?

Lowering the car (swift springs will lower it) also affects rollcenter. It makes the car roll more in turns (though typically lowering springs are also stiffer, counter acting much of the change). But its not an even change. The rear will gain more of a change in roll leverage (distance between roll center and center of gravity), meaning the increase in roll will be more at the rear. Since you're also softening the rear compared to front bias (not stiffening the rear as much as the front), even as rear roll increases, there will be a shift in roll behavior as well. This will have an effect on the front to rear bias as well.

You can start to see how complex a question it is. You're changing several things at once (tire width, spring rates, arb rates and ride height), that exist in a complex, dynamic relationship, and asking what the end result will be.

Unless someone has experience with all the same changes, they are really jist guessing, and its a hard guess to make.

Periodoc

Sounds good to me: leave the sway bars in and use less compliant bushings. Once I see how it handles, I can go from there. I've read that 245 square often does not require rollling the front fenders, so I will try that. I've been open tracking an 86 Mustang with a Mass Air 351 and largely Griggs suspension off and on since 1994 and have my doors blown off by s2K's. So, I want to try some of that.

gptoyz

Actually it's possible to fit 255/40/17 all the way around without having to modify the fenders. There's a few ways to skin this cat. mostly it will come down to the combination of tire/wheel & camber joints.

Let's start with setups that definitely do not work:
255/40/17 Hankook RS3 or Dunlop Direzza Z2 star spec or greater width tire (assuming this includes Bridgestone RE71R) + Wedsport TC105N 17x9 +49; even if you use a camber joint that doesn't pull the upper A-arm in towards the chassis, the rear will require a roll & tab relocate. This means that any wheel with a lower offset will absolutely not fit and it's not even close. Granted I haven't tried a camber setting greater than -3.4, but at that point you aren't gaining any performance on track.

Next let's go with a setup that definitely DOES work:
255/40/17 Bridgestone RE71R + J's Racing Offset camber joint S2 + 17x9 + 60 Enkei PF01 with -2.8 camber all the way around. No problems at all with stock fenders. A word of warning, it can and probably will run the inner fender liners and fender liner buttons at the 12 o'clock position of the fender liner in the wheel well.

Obviously driving an s2000 around the track you'll want to increase the amount of front camber. The rear in stock form can achieve greater than -3 degrees of camber but the front is camber/caster limited. There's a couple of different methods to increase negative camber in the front including:
Offset Lower Camber Joints
Offset upper Camber Joints
Eccentric Control Arm Bushings

The easiest way to clear the front fender is to use the Upper Offset Camber joint that allows the tire to lean in from the top rather than being pushed outward from the bottom. The problem with the Upper Offset camber joint is that they tend to shift making alignment consistency a battle. This can be addressed by tack welding the ball joint in place.
The most convenient method to increase the negative camber and for a fairly robust installation, use an aftermarket ball joint that pushes the lower A arm outward. I would personally recommend the spoon as it is made out of steel.

Periodoc

Great information. Thanks.