[glamcem]

I had a chance to attend a private event this past Saturday at the ORP with a special permission we were able to rent the track (limited to 6 attendees, extra measures taken due to virus etc).

It was rather a hot day and I missed the opportunity to run it at the best time which is early in the morning (once again!). I noticed that I forgot my Hans device at home so without the paddings harnesses hurt so bad so I had to go back to paddock and figure out what to do.

Luckily I had some extra trailer tie down paddings to be used for wheels and I cut it in half and wrap around the harnesses to give some extra cushion. It was a ghetto solution but it worked so I am not complaining







Also, titanium shims and/or brake deflectors definitely work. Even after many sessions on a hot day with aggressive tires, I couldn't see any discoloration on the calipers like may previous car. Temp sticker shows the temps dropped more than 100F degrees. Brake fade was almost non existent so I am very happy with how it turned out.



Now let's talk about the RR vs SC3R tire comparison. Since it was a hot day (worse than the last time) and I missed the opportunity of driving in early sessions, I can say there's some room for improvement. Bumping up the tire size on the RR set (from 295/30/18 on 18x10" wheels to 315/30/18" on 18x10.5") really helped to defeat the corner entry understeer and turn in.

Since last time, I tried the SC3R tires in the afternoon session, I wanted to try them first to see if I could best my previous PB. However, by the time I fixed the quirks and started running the car it was around 10:30 and the ambient temps were about 70s. (I typically see my PBs at this track when it's around 50s in the early morning)

I couldn't see an improvement since the before noon conditions this time were similar the afternoon conditions last time One thing is clear though, SC3R tires were more consistent than RR tires regardless of the condition while it lasted I ended up cording the LF tire (driver front) after about 5 sessions on them on the outer edge. Since the track configuration is CW and ORP with extended sessions, elevation changes, off camber turns and extra heat is a torture test on the tires, I didn't expect them to last too long but still.. I am very surprised. The other three tires looked just fine both inner and outer wear seemed normal. I will start rotating them after 2-3 sessions side by side for equal wear from now on.

Front driver side


Front passenger side


I also noticed that Apex now has 19x12" wheels for Camaro in stock so I ordered a couple wheels from them. I also ordered 325/30/19 SC3R tires so that I will have my guy move the rear tires (305s) to front and have a staggered setup once again. I feel like I am losing some time at corner exit and couldn't be on the gas as quick as I wanted to. Added rear grip should take care of that. Also bumping up the size will extend the life of the tires too.


My best time with the SC3Rs was 1:52.9 almost identical to the last time (1:52.8) I believe I still can shave another second and take it to 1:51s on a better day and/or with more grip in the rear. I'll see about that.

Best time with the RRs (315 SQ) was 1:55.7 but on much warmer conditions. So SC3Rs was about 2.8 seconds faster than the RRs but when track temps were much better (69-70 F). Since it's typical to see 1.5-2 seconds difference between morning and afternoon sessions, when it's taken to an account I'd say the actual difference between the RR and SC3R tires should be about ~1 second.

For instance, right before the lunch break when the track temps reached 75, my best lap with the SC3Rs was 1:53.9 (or only 1.8 seconds faster than the RRs) so that alone should give an idea about the effect of only 5 degree change.

One important thing to mention, heat affects the RRs more than the SC3Rs so on equal conditions and colder day. Also, even though the RRs are 315s, when they put on 11" wide wheels, 305 SC3Rs were still wider .. they run wider for sure. My starting/cold pressures were 27 PSI all around on both sets and they were stable at around 32-33psi as hot pressures.

When it comes to cold/hot pressures for Toyo RR there are two schools of thought:
On a colder/warm day , for the best lap time it's better to start at around 27 PSI and keep it around 32-33 PSI when they're hot. However, Toyo recommends 33-34 PSI starting pressures and 36-42 psi operating temps. Anything between 34-36 PSI hot pressure is the weak zone. My friend mentioned that he had good results when he increased the pressures on hot day, his lap times were slightly behind than running them first method but they were more stable. I have never tried those higher pressures on the RRs but since the track temps passed 80F degrees I noticed that I couldn't even do below 1:56. Then I returned to paddock and added 5 psi all around to keep it above 36 psi and boom I immediately dropped another second and did 1:55.7

When all things considered, and within the ideal conditions I am almost sure RRs would be about 1 second slower than the SC3Rs IMO but they are not like heat resistant like R7s or SC3Rs but they are still much better than tires like NT01, RE71Rs or R888Rs for consistency especially when followed the Toyo's recommendation. They are also cost effective tires with very communicative manners.

Video from the event:

[TRZ06]

I think the conclusion that is coming about over the last couple years is that Goodyear really nailed it with the SC3 & SC3R tires.

We all know they were made specifically for the 1LE's , but they really are a win all around.

The standard SC3 tires grip just a hair under the Sport Cup 2 tires , but with far better consistency and heat resistant. While the SC3R's are damn near as good as a true slick.

I hope that GM reverts back to GY as OEM on the Corvette for the C8 Z06.

[Redlinez]

Never thought I would say I "love" Goodyear tires.

[TRZ06]

Originally Posted by Redlinez

Never thought I would say I "love" Goodyear tires.

Iv'e always been a fan since the C5 Z06 days.

They are not the greatest in standing water, but they have always had stiff sidewalls, which give them a nice crisp initial turn-in feel.

Michelin's use much softer sidewalls, which are fine for a 3100lb GT3, but not so much for heavier cars. They also use the bi-tread compound, which tends to wear the outer edge of the tires way before the middle and inner parts of the tire.

[seanblurr]

I ended up ordering a set of the 18" RR's to compare. I spoke to a tire guru who recommended HIGH pressures on the RR's, especially for a heavy car. ~39-42 psi hot.

[Redlinez]

The Goodyear runflats that came on my 17 SS were the absolute worst tires ever in rain. I've been driving since 1987 and nothing has come close to scaring me like those tires did. While the 1LE spec Goodyears are much better, they still are dicey in the rain. I replaced my Goodyear runflats with the Michelin 4S's, I noticed the softer sidewall immediately, which I don't care for. They did perform well for me at HPDE twice and lasted 28,000 miles. They were also fantastic in the rain. Just don't know if I'm gonna pony up $1500-1600 for them when I can get the OEM GY's for under $1k.

Glacem- Also, titanium shims and/or brake deflectors definitely work. Even after many sessions on a hot day with aggressive tires, I couldn't see any discoloration on the calipers like may previous car. Temp sticker shows the temps dropped more than 100F degrees. Brake fade was almost non existent so I am very happy with how it turned out.
Are you talking about between the pad and caliper? Where did you find these?

[TheRealJA105]

Originally Posted by TRZ06

The standard SC3 tires grip just a hair under the Sport Cup 2 tires , but with far better consistency and heat resistant. While the SC3R's are damn near as good as a true slick.

Nailed it

[TrackClub]

Originally Posted by TheRealJA105

Nailed it

+1

[cirpower]

Looking really good there! How much weight do you gain by removing the passenger seat and back seats? Is the passenger seat difficult to remove?

[TrackClub]

Originally Posted by seanblurr

I ended up ordering a set of the 18" RR's to compare. I spoke to a tire guru who recommended HIGH pressures on the RR's, especially for a heavy car. ~39-42 psi hot.

Looking fwd to your comparison. Btw do you swap G3R fronts every couple of sessions to get about 3 days out of them? Do they end up cording on the inside, or outside? Thanks!

[glamcem]

Originally Posted by Redlinez

Are you talking about between the pad and caliper? Where did you find these?

Yes, Between pistons and pad. I found them at KNS brakes this should be for SS 1LE front

https://knsbrakes.com/c/car-item/496...+Shims+-+Front

and this should be for the ZLE front
https://knsbrakes.com/c/car-item/535...+Shims+-+Front

[glamcem]

Originally Posted by TrackClub

Looking fwd to your comparison. Btw do you swap G3R fronts every couple of sessions to get about 3 days out of them? Do they end up cording on the inside, or outside? Thanks!

They cord on the inside on ZLEs . There was a discussion on 1LE R (facebook page). Some believe it's because of the ZLEs LCA bushing design that changes the dynamic toe during turns.

[glamcem]

Originally Posted by seanblurr

I ended up ordering a set of the 18" RR's to compare. I spoke to a tire guru who recommended HIGH pressures on the RR's, especially for a heavy car. ~39-42 psi hot.

Sean if it's early in the morning or track temps are not that hot (below 70F degrees), I would also try starting at 26-27PSI and use the 32-33 PSI as target pressures. You will notice it will be faster than the Toyo's recommended pressures 36-42PSI (hot) . The problem with starting lower, they warm up very quickly (much faster than SC3Rs for sure) so after the very first lap 2-4 laps are the fastest.

My friend who has C7 Z06 (3550 lbs car) is only 1 second behind the R7s (both fresh tires and similar conditions and same size 315/345). I wish I could use slightly wider tires at the rear (like 345s maybe) I am almost sure I could do better as car felt like it could use a bit more rear grip since now I have tons of grip and roll resistance up front.

[seanblurr]

I'm torn on the setup, as I've heard different things from knowledgable people on camber and tire pressures.

I'm thinking I will continue to run about -2.9 and just go from there.

I talked to Phill from Philstires about pressures of the RR's on heavier cars. Luckily NASA Spec Mustang (05~ GT's) use the RR as their spec tire, so there is some knowledge on heavier cars. Phill was saying there was a split on lower (34psi) and higher (41psi) between different drivers. He eered on the side of the higher PSI set up driver, as he was a national level winner. The guy who preferred the lower pressures was a mid-pack guy. He mentioned the lower pressures are perceived as fast, but don't last as long.