MC 968CS

Hi. I have an event coming up where I am considering running slicks not the usual r specs, and need some help please. Event has 8x20 min sessions.

I have a set of 18" (9" 11") and 19" (9" 12") track rims. I just want to turn up and know it will work. I run approx -4 front - 3 rear Camber, pretty much cup suspension. All Porsche factory Motorsport parts and custom made shocks.

1. What size slicks work on the car in 18" ? In Pirelli (thinking medium) and in Michelin. Both accessible here. Pirelli may be better buying.
2. Any insights on 19'' slicks and size, brand ?

(I have read older forum answers...they seem to divert to stuffing much much wider sizes in with more mods, often on wide body cars including gt2 996 which seems irrelevant. I don't think I need to go that path ? and my cars not wide body.)

Thanks in advance for any guidance to any question. Happy driving.

pbu

Thinking of doing the same myself.

Ran with a guy with an identical setup to you and me with R7s. In the morning we were about even. (low 1:50s pace at orp) Mid day he switched to sticker Pirelli DS front DM rear. He pulled every corner and probably made up 1 second per min on me. From my perspective, not crazy grip where spring rate changes are needed and your alignment is in the ballpark to slap on and go fast out of the box. Might be worth a shot - its probably my next tire as I should probably match or one up thia guy for our next meeting.

Good luck.

MC 968CS

Cool. Now we just need some input to help!

grrrmonster

Love running slicks. The proper sizes for GT3 on 18 inch wheels (at least for a 997.1) are
25/64-18 for front and 30/68-18 for rear in Michelin sizing. Other brands the size is 245/645-18 front and 305/645-18. Some debate with the techs I use on that rear sizing- one guy argues the proper rake of car is maintained by using 305/680-18 rear. I've run both with no real issues. But then again, I'm out of the points for this season DE championship contention 😋

I've run scrub tires a lot- sometimes 3-4 weekends out of a set, sometimes barely made it thru one weekend. Ran a new set of Michelins- got 55 heat cycles out of them- nearly a full season for me. Even cycled out they're better than Nittos

They do prefer a lot of negative camber and ideally they work well at 30psi hot

They are dangerous when cold- especially a new set- like hockey skates until you get about three laps and some heat in them. You have to be very disciplined and careful about getting heat in them before you start pushing.

You WILL have more suspension wear if you run these. Higher g loads will wear on control arms, ball joints, mounts etc. especially if you're still running a street suspension. My car had been upgraded to solid motor mounts, Gard diff, spherical bearings everywhere etc before started running stickers

They are addictive however. Consider yourself warned

MC 968CS

Thanks. That's great feedback. Really appreciate the clarity.

Anyone got any further insight into the sizing for other brands rears or 19'' slick feedback?

RobT 394

On a 997.1 RS I ran the 325/660-18 Pirelli DH on rear with 245/645-18 as suggested by GRRRMONSTER. Enjoy, they do last a long time and are addictive. Nothing like that one magical session when new.

F1CrazyDriver

If you want a sniff of the crack, i have 18's foregelines mounted / balanced, tpms, with Pirelli DH's that i'll be selling shortly as i'm moving out of the country. I'll be back in the States next week. Ping me !