[khcoaching]

#12 Ridge Motorsport Park September 30, 2022

Without Chicane 1:45.07 -


I wasn't sure if I was going to be bring the car out for this one. The original plan was to drive the day with my son in his GTI and not drive mine, but since the car just came out of a full service and updated alignment, I had to try it. We signed up for an On Grid day, where there were run group and the Time Attack. Going in, I knew the 19" 3Rs were smoked and my front pads were going to be good for maybe 3 sessions. The day started out misty and a slightly damp track and the sun came out about 2pm. Both my sessions I had to use the wipers a couple of times a lap to clear the mist.

Changes -

Alignment:

- At the last day with with Randy, we did a mix of bikes and cars and I coached a rider who is the lead data tech for a pretty major race team. It was great to speak data with him and he had some insight for some new alignment specs, based on my feedback with the car. We went with -

Front -3.6 and .08 toe OUT
Rear - 2.7 and .04 toe IN

Service:

Nothing major here except the rear diff fluid was super dirty even though it was only 1500 miles since the last oil change.

Results:

Right out of the gate, the car was better on entry. The track needed to dry all the way out, but even with the low grip on shagged tires, I did a 46.3, with a passenger. In the 2nd session, I was able to push and easily dropped into the 45s, beating my PB by a tenth. 45.07 vs 45.18 even though I only did a few laps. The car was much much better on straight up and down braking and after turn in to brake release. In fact, I was having to change the way I used the brakes with the additional grip and confidence. Rear grip was also better once the tires built heat. The only negative was I was focused on feeling the new settings and got greedy on direction, not doing a good job of respecting being precise in the longer radius corners, making it push. The nice thing was the car continued to tun somewhat when it did push.

Here is a data graph with the previous alignment and the new alignment. (Red previous PB - Blue new alignment) There are some differences for sure on driver input, but the differences can been seen more on the brake pressure side, achieving a faster entry due to having to use less brake pressure. The fact this was done on smoked tires, is very encouraging.



Unfortunately, I felt a vibration halfway through the 2nd session and pulled in. The L/F tire had corded pretty good and I had to call the day. Bummed, but a great problem to have...

I'm not sure when I'll drive it next, but hopefully I can get out for a day with some freshie's before the end of the year.

[Zl1+911]

Ken is that the L/F inside corded or outside? Thx

[khcoaching]

Originally Posted by Zl1+911

Ken is that the L/F inside corded or outside? Thx

It was on the the L/F inside....BUT, I have never had an issue with the fronts cording, only the inside rears on 3Rs. The corded tire was previously on the L/R before this day and I knew it would be thin...

Ken

[cdb95z28]

Originally Posted by khcoaching

#10 Ridge Motorsport Park July 22nd 2022

Without Chicane 1:45.13 -


OK, NOW we are getting somewhere. My complaint last time out the car losing grip mid corner and me thinking the 3Rs were at the limit. Since the current set of 3Rs still had another half a day left in them, I wanted to make a change, while using the same set of tires....I felt the next step was swaybars, the question was softer or stiffer? I ended up going stiffer, installing the Hotchkis front and BMR rear bar as suggested many times here on the forum.

Installation wasn't horrible. The front was actually pretty easy and the hardest part was snaking the rear bar out because of changing them on the ground....no lift sucks. I ended up installing both in the #2 hole.

My plan was to try them at a track day where my son was going to do his first day, but I had a last min notice for a day where the weather was cool and hopefully minimum signups. The day was lightly attended, but the speed disparity was pretty high and I only drove 3 sessions, as I met my goal and the chance of getting a clean lap was low because the A/B run groups were combined. First lap I immediately noticed a difference with the car sharper mid corner. As the tires warmed up, the second thing I noticed was a big increase in rear side grip, especially when driving off a corner. Awesome so far! First session I matched my PB and I needed to think about how to drive the car a bit differently to take advantage of new setup.

The new setup offered much more mid corner and exit grip, so I needed to be very deliberate with my braking, as not to carry too much brake pressure, too deeply. Once I figured that out, times dropped and I was able to consistently run under my PB and then hit a 45.13, getting slightly held up. (I saw multiple 44.8s and 44.9s, but never got a clean lap.)
I ended after 2 30 minute sessions (3 runs) as I was cording one tire, brakes were getting low and I wanted to save them for tomorrow.

Overall, This was the change I have been looking for and no doubt with fresh tires we are in the mid 44s. (For reference, at the Global Time Attack last weekend, the Street class was won with a 44.69 in a very prepped Supra with a great driver)

Last time difference. (Blue is swaybars) Note - I changed may line in T3-T5 as what I was doing was adding risk)




Lateral G difference - (Blue is swaybars)



Edit -

I think the biggest difference is being able to run at near PB pace on worn tires, on demand, instead of having my hair on fire the entire time.

Originally Posted by khcoaching

#11 Ridge Motorsport Park July 23rd 2022

With Chicane 1:52.01 -

So......I wasn't planning on any hard lapping today, as this day was about taking my son to his first ever trackday and he was going to driving the Camaro. He did great and and he now needs to work a lot of overtime to be able to afford a track car!

When I was driving home from the track on the 22nd, I though the car lagged a little bit of crispness on turn-in, like there was a delay. When I got home, I added 2 turns of front swaybar preload and left the car as is. The tires were pretty worn, but with my son driving most of the day, I didn't worry about it. We also were running the chicane, so I wan't too jacked up about running any laps.

I did a few laps at pace, and the difference in the swaybar preload was spot on, eliminating the dead spot as I turned in and also helped the car steer down to the slow point. Feel wise, this was a major improvement. I booted my son and did 2 short sessions at pace and the data is pretty clear on how much the sway bars have helped, I was .7 faster on smoked tires compared to new tires, tire wear looks better and the car is a joy to drive.

Here is a data graph from my last Chicane session on new 3Rs....The ability to run T1 flat was gobsmacking, I'm on the rev limiter in 3rd and the car just flat hooks. (Blue is today's run)



When looking for my last chicane session, I ran across a graph with the car all stock using the chicane.....holy crap, what a difference. (Blue is today's run)

[

I'm not sure when I'll be driving next, as I'm on the east coast for a couple of months and the car needs a full service...

Ken

Going back to these two posts....
I'm surprised that going to the stiffer Hotchkis/BMR bars over OE SS 1LE bars yielded better 3R grip. Between the stiff DSSV springs rates combined with your previously used setup of the OE SS 1LE bars (which are stiffer than the ZLE bars) just adds to that surprise.

Bar stiffness:
Hotchkis/BMR>SS 1LE>ZLE

Do you think that maybe the increase in grip is a result of better camber control of a flatter platform? Or just the F/R delta of the Hotchkis/BMR settings brought the balance in mid corner?

Also on the front bar preload, did you shorten both front endlinks or just one?

Thank You

[khcoaching]

Originally Posted by cdb95z28

Going back to these two posts....
I'm surprised that going to the stiffer Hotchkis/BMR bars over OE SS 1LE bars yielded better 3R grip. Between the stiff DSSV springs rates combined with your previously used setup of the OE SS 1LE bars (which are stiffer than the ZLE bars) just adds to that surprise.

Bar stiffness:
Hotchkis/BMR>SS 1LE>ZLE

Do you think that maybe the increase in grip is a result of better camber control of a flatter platform? Or just the F/R delta of the Hotchkis/BMR settings brought the balance in mid corner?

Trust me, I went back and forth whether to try the softer ZLE bar set up or these. It wasn't until I consulted with my chassis contact that had me try the stiffer setup and I am glad I did. I think it is camber control as tire wear improved significantly with the setup. I think it is very well balanced and Randy's comments echoed this.


Also on the front bar preload, did you shorten both front endlinks or just one?

I added 2 turn of preload to each end link to stiffen the front bar....

Thank You

See above!

[cdb95z28]

Very interesting on the bars, Ken, thank you.

Looking at your latest alignment specs, I see you spec'd .04* toe in at the rear, which is about .018". That is less toe in than the GM specs (.10*). What was the thought on going with less toe in vs what you had prior? I would think going less toe in would be detrimental to getting the power down on exit, but I wonder with the eLSD programming that might not be the case.

EDIT. Ken said the specs were in inches.

[khcoaching]

Originally Posted by cdb95z28

Very interesting on the bars, Ken, thank you.

Looking at your latest alignment specs, I see you spec'd .04* toe in at the rear, which is about .018". That is less toe in than the GM specs (.01*). What was the thought on going with less toe in vs what you had prior? I would think going less toe in would be detrimental to getting the power down on exit, but I wonder with the eLSD programming that might not be the case.

I was at a private event where we did a bike/car day and I was working with a student (on motorcycles) who jut happened to be the data engineer for a well known private BMW/Mercedes team. He also has done chassis engineering and I was talking to him about the car. He looked at my last alignment, asked about what I needed the car to do better and gave me this specs to try. The idea was to lessen the tendency for push as the tires wear and still keep the ability for the car to rotate.

It certainly is much much better on straight up and down braking, as well as turn in. Exit grip was also better, no clue why. Unfortunately I did test this on very worn tires and not doubt it will be better with freshies.

Ken

[cdb95z28]

Originally Posted by khcoaching

See above!

What are your Hotchkis/BMR bars set at? Full soft?

Since the typical aftermarket bar is attached to the chassis with a poly mounting bushing that does not grip the bar as tight as the OE super tight mounting bushing I wonder if the bar dynamics are playing a part in the results of the Hotchkis/BMR setup.

Happy Thanksgiving!

[khcoaching]

Originally Posted by cdb95z28

What are your Hotchkis/BMR bars set at? Full soft?

Since the typical aftermarket bar is attached to the chassis with a poly mounting bushing that does not grip the bar as tight as the OE super tight mounting bushing I wonder if the bar dynamics are playing a part in the results of the Hotchkis/BMR setup.

Happy Thanksgiving!

I went with the #2 position on both front and rear and am pretty darn happy with where they are at.

Ken

[khcoaching]

Not really an update, but a fun comparison I was able to do -

https://www.camaro6.com/forums/showthread.php?t=614504

[MightyBobo]

Originally Posted by khcoaching

Not really an update, but a fun comparison I was able to do -

https://www.camaro6.com/forums/showthread.php?t=614504

I think that's truly a testament to just how good an SS 1LE is. Nice comparison!

[khcoaching]

^^

It's pretty staggering what our cars are capable of.

On another note, I have 3 days scheduled with my car in the next 2 weeks. Looking forward to some proper updates!

Ken

[Mavrick81]

What days are you going to be at the track? I live about 10 minutes away from the Ridge, and would enjoy watching you lap your Camaro on the track. I have a Zl1 on order that I am hoping to bring to the track this summer and I will be looking for other Camaro owners to meet up with.



Eric

[khcoaching]

Originally Posted by Mavrick81

What days are you going to be at the track? I live about 10 minutes away from the Ridge, and would enjoy watching you lap your Camaro on the track. I have a Zl1 on order that I am hoping to bring to the track this summer and I will be looking for other Camaro owners to meet up with.



Eric

Right now, March 31 and April 7/8th.

Ken