Manifold

I tend to agree. The 991 GT3 is fast, but 6 cup on slicks has much more grip than the GT3 on OEM R-comp tires. At Summit Point, very well driven 6 cups are doing 16s, while a 991 GT3 driver will really need to be on it to do 19s.

Macca

My experience on a shorter track over here supports this. 2.8km track 6 Cup on a used Michi Blue is around 2.5s quicker than 991 GT3 in stock trim driven well (thats 1.10 v 1.128).

The only thing holidng back the GT3 is the tyres. My 993 track car n Hankook Z221 Dot rated pulls same G as my GT3 in tight corners. The rubber is just that much stickier. If those tyres were on my GT3 it would be 1.5s+ per lap quicker on same track. With some improved Geo and better pads probably the difference would be zero same driver.

Keith Verges - Dallas

The GT3 is entirely tire-challenged and Porsche was very clever. Give it blingy 20" wheels that look cool but make it impossible to install really sticky rubber. That is the biggest complaint I have about the GT3. The wheels are big, heavy and expensive and make the consumables expensive and of limited availability. If I could install cup tires, I'd have a great supply of take-offs at reasonable prices.

Macca

Agree with you 100%. mPSC2 last me 4 track days and some road work. Sending me broke!

R.Deacon

Ditto on the broke
you must be doing some special road work to only get 4 t days

I figure 6+ T days, maybe I not driving fast enough yet .

Manifold

The tire cost probably hurts more than any other consumable. I'm used to getting maybe 10 to 15 days out of the NT01, running them almost until they cord without too much loss of grip, whereas I seem to get less than 30 decent heat cycles out of the Cup 2, which is about half the life of the NT01 from a tire that's also much more expensive.

Macca

Yeah. Ok. 5 days at a pinch (30-35 cycles) but they drop off 1-1.5s a lap somewhere in the 5th day and although they would have a few thousand more road km in them seems silly to track them further. Otherwise I might as well use my 993 as its only 3.5s a lap slower than the GT3 on new tyres and costs under half the cost to run! Seems a bit pointless running the latest 150k GT3 at the track to be 1.5s slower because of the heat cycled tyres. Personal thing of course but in for a penny in for s pound as the British would say...,,

Alot of the roadwork I do is fast back road rural stuff.


Bring on the Nt01 I say :-). They would be quicker and the shoulders

Keith Verges - Dallas

With stock alignment and being too lazy to rotate I destroyed my Dunlops in 6 30 min sessions.

R.Deacon

Macca

I bet our usage life is much closer , as the heat cycle count would be more accurate ruler than T-days ; I bet your getting more seat time per day than I usual get , typically 4 x 30 min sessions
and sometimes only 3 sessions , so for 4 cycles over 6 days 24 heat cycles , I still think the cup2
has a little longer life than the cup1 had. for round numbers average speed north of 90 mph or
45 miles per session , so if I can get 30 cycles (7.5 days) @ 45 miles per session = approx. 1,350
track miles per set if I rotate as needed. and typically can get one more days out of rears,
if push for max use , but I have been going fresh all around when the fronts are done.
That's not counting road work for me is very easy flat smooth Florida surface

R.Deacon

wow Keith that translates to some expensive laps thanks for sharing that
as I will totally avoid those sneakers, I have yet to try the trofeos .

as Macca saying we need a Nitto streetable R compound

Macca

We are on the same page. I run 6-7 sessions a day at 15 min a session. So Im getting around 105 mins a day. On a heat cycle basis your 7.5 days is my 4. Im running only 600 miles in 4 days. For the style of events Im running Im getting much less value than yu per mile from my tyres. Unfortunately 15 min sessions is the standard unless we open pitlane with a half day exclusive track hire - which we d 3-4 times a year - I now know to remember to stay out there for a good 30 mins to get the value from each heat cycle!

I used t think your 30 min sessions were too long (tyres gone ff a bit by then) but I now see they are mre cst effective. I think 6 x 20 min sessions a day would be a good balance for me..

Macca

Keith, Ive reverted t stock settings and dont rotate. I think you need t get off that Dunlop heroin and onto the Michelin smack real fast :-)

rosenbergendo

Pretty sure 991 GT3 on Trofeo R or upcoming R7's will be same or faster than 996 Cup.

Manifold

Trofeo R may provide a little more grip than Cup 2, but R7 provides way more grip, and should get us close to 6 cup on slicks. But there's still the warranty issue, with an engine that hasn't proven to be entirely bulletproof ...

MileHigh911

I think Porsche would have trouble denying warranty with this engine's history. Also, what exactly does the warranty say? Just "No slicks". The R7 is a DOT radial tire. They are not a true racing slick.