[Stocktastic]

It's almost like your MRC was still in Tour.

[JeffFox]

Thank you Travis and forum members for the good information

[cdb95z28]

The first laps of the day or of a session after tire temps/pressures have dropped are important. Putting the hammer down before the pressures are very near optimum will abuse the outer shoulder. I’ve felt the sidewalls lay over, more often in Pitt Race’s turn 4. What are you cold pressures?
Be aware that going nuts on the static camber will be abusive to the inner shoulders. This is where finding optimum caster helps. Caster helps the dynamic camber on both fronts in a corner. It will help the more loaded outer tire in a turn by adding dynamic negative camber and conversely, it will help the inner less loaded front tire by subtracting the dynamic negative camber. But, since there is no free lunch, addition caster beyond OE may create bumpsteer. Been there, done that.
The comment about more grip=more chassis roll is spot on. An easy change would be to swap in stiffer anti roll bars, if anyone makes them. But without any hard data on actual stiffness differences, it would just be a guessing game. Any change to the roll stiffness may also negatively change how the MRC performs.

[travislambert]

I ordered the DSSV kit and ZL1 1LE rear sway bar Friday. Hopefully I'll get a couple track days with them before the end of the season.

[mlee]

Tire Rack really provided an awesome response. Totally surprised by that.

One reason I'm switching to 1LE is the suspension. Will be interested to hear your review on the DSSV. As for tires I'll probably use the Goodyears for the track and I have a second set of OE wheels on order for tires TBD.

I wonder if 20" tires with the smaller sidewalls has anything to do with this.

[travislambert]

Originally Posted by mlee

Tire Rack really provided an awesome response. Totally surprised by that.

One reason I'm switching to 1LE is the suspension. Will be interested to hear your review on the DSSV. As for tires I'll probably use the Goodyears for the track and I have a second set of OE wheels on order for tires TBD.

I wonder if 20" tires with the smaller sidewalls has anything to do with this.

Their response was good. Unfortunately, their response is just a roundabout way of saying I need to change my suspension to match the tires.

I'm really looking forward to the DSSVs. It should put me in a unique position to evaluate MRC vs DSSV without other variables like aero, wheel size, tires, 1LE secret sauce software, etc.. we'll see how it goes.

I'm sure the sidewalls make a difference, but I could see a stiffer sidewall perhaps being a benefit...who knows though. PittRace is just really hard on tires, and I'm bad about sliding the front around every turn anyway. I have a new set of R7s. I plan to watch the pressures a little more closely and try not to run them too hard for the first couple laps of each session.

[Mountain]

Originally Posted by travislambert

Their response was good. Unfortunately, their response is just a roundabout way of saying I need to change my suspension to match the tires.

I'm really looking forward to the DSSVs. It should put me in a unique position to evaluate MRC vs DSSV without other variables like aero, wheel size, tires, 1LE secret sauce software, etc.. we'll see how it goes.

I'm sure the sidewalls make a difference, but I could see a stiffer sidewall perhaps being a benefit...who knows though. PittRace is just really hard on tires, and I'm bad about sliding the front around every turn anyway. I have a new set of R7s. I plan to watch the pressures a little more closely and try not to run them too hard for the first couple laps of each session.

On one hand, the shorter sidewall effectively gives a stiffer package to resist the slip/distortion of the tire to roll under.

On the other hand, a taller sidewall effectively gives a more compliant package, possibly lowering the spring rate of the tire, lessening the work of the springs/dampers.

Haven't people run PWC Pirelli slicks? Those are a fairly durable, sticky and soft-sidewall-ed tire... The Mustang guys use them a lot on medium static camber (-2.5 to -3.0) cars.

[Mountain]

Found this when looking for DH slicks for sale. Something I've not seen stated by PWC before, but I guess that was the case until the 2017 season:

[travislambert]

Originally Posted by Mountain

On one hand, the shorter sidewall effectively gives a stiffer package to resist the slip/distortion of the tire to roll under.

On the other hand, a taller sidewall effectively gives a more compliant package, possibly lowering the spring rate of the tire, lessening the work of the springs/dampers.

Haven't people run PWC Pirelli slicks? Those are a fairly durable, sticky and soft-sidewall-ed tire... The Mustang guys use them a lot on medium static camber (-2.5 to -3.0) cars.

With a 20" wheel, options are pretty limited. At some point, I may drop to a 19" wheel to expand my options.

[neenja_jenkins]

Originally Posted by mlee

Tire Rack really provided an awesome response. Totally surprised by that.

I was thinking the exact same thing.

[Chris V]

Originally Posted by neenja_jenkins

I was thinking the exact same thing.

Don’t be surprised, Tire Rack is the real deal. Those guys know their stuff, and race too.

[travislambert]

Originally Posted by Chris V

Don’t be surprised, Tire Rack is the real deal. Those guys know their stuff, and race too.

I'm putting their response to the test this weekend. I have solid cradle mounts, an FEA suspension, and fresh Hoosiers I'll be maxing the camber out tomorrow hopefully getting close to -4 in the front.

[Chris V]

How did it go today?

[R3ctivision]

It sounds like their advice was spot on. I do agree that stickier tires needs a stiffer suspension to utilize the grip. Fast cars are engineered with a specific tire compound in mind nowadays.

Consider ZL1/SS 1LE with GY S3 vs ZLE with GY S3R. Hard mounted suspension, DSSV, higher spring and sway rates, all to handle the higher grip from the R tires. And those aren't even slicks!

For this reason I hate to play the devil's advocate, but you may enjoy your car more on stock tires or ones with similarly matched grip. Otherwise, might as well trade for a ZLE and get the complete package at once.