sign up here:

http://www.6speedonline.com/forums/n...mber-24-a.html


i'm all signed up and ready to go, stoptechs came in today

 

Nice! Yeah i got the link in email today, gotta check the schedule so I dont end up like I did last time. Pay then not go

 

its 3 weeks out man, make this your schedule, clients be damned...

 

Signed-up. I'll be there.

 

goddamnitsonofabitch!!! i won't have my gti rebuilt by then. will there be another one a couple weeks after this one? please say yes...

 

prolly not due to unpredictable weather.

just take your g35

 

Anyone planning to run R-Comps on their Z/G that day?

 

rotors are warped slightly and my tires are all-seasons. i don't wanna end up like that m3 did last time. the brake systems are definitely a weak link on these cars.

 

I went to the PGP lapping day today. It was pretty revealing as to the performance of the 350Z at that venue. Hopefully this post will be helpful to the guys that run or plan to run at PGP.

I’m pretty much close to stock, just a couple of mods; Nismo exhaust, Nismo S-Tune springs and dampers, Stillen Sways, K&N filters, and Project Mu brake pads. The main difference between today’s outing and the last one I did back in July was the wheel and tire combo I used. Back in July I ran on Falken Azenis RT-615’s (275/40-17, square), this time I was on Falken FK-452 (275/35-18 and 275/40-18, staggered). Both times were run in the preferred counter-clockwise direction.

Back in July my best lap time was a 1:17.3X. The FK452 is no were nearly as grippy a compound as a RT-615 nor is the sidewall construction as stiff. It’s pretty much regarded as an All-Season performance tire where the 615 is a top choice of street tire for track and autocross. Knowing this I would’ve been happy if I would have ended up w/ one lap in the 1:18.XX range. My fastest lap today was a transponder confirmed time of 1:16.61. That was completely unexpected. As of my 3rd session nearly all my times for the rest of the day were consistently in the 1:17.XX and 1:16.XX range. The only time I got a lap in the 1:18.XX range was when I dipped both wheels off the track coming out of Turn 11. After the first PGP outing I felt that the 350Z (and quite possibly the 370Z) does very well at PGP. After today I am confident of that assessment.

Initially I thought that square set of 17” Rt-615’s would do better than the 18” FK452’s. If it was the same size tire vs. the same size tire the 615’s would probably be nearly a second faster but I believe that the entire difference in performance was in the size, more specifically the staggered set-up. I believe the following reasons contributed to the better performance of the FK452 set-up:

- By running in the properly staggered ratio I was able to get optimal braking. W/ the square set-up I was getting Ice mode braking at the end of 3 high speed areas. I noticed that this time my front brakes were REALLY getting a workout. Brake fade was a lot more apparent this time. At the end of one session I used a IR thermometer and measured the hottest part of the front rotor at 640F! And this was after a cool down lap. Smoke coming out of my front wheel wells after I parked in the pits was not uncommon sight today. The non-Brembo front brakes on a ’07 even w/ track pads on are insufficient for more than maybe 4 laps (still haven’t completely changed over to RBF600). I’ll definitely need cooling ducts or something else if I plan to make use of the OEM brakes.

- The shorter side wall of the 18” wheels seem to allow for better handling. Yeah, fairly obvious, but even compared to the super stiff 615’s side wall the aspect ratio seemed to make more of a difference than the construction of the tire.

- By having a rear wheel diameter 1” larger than what I was running would allow for about 4% greater top speed in the front and back straights. Infact this time around I was unable to bounce off the rev limiter on the back straight and spent less time at the rev limit on the front straight. I thought that corner exit might be compromised but the corners leading into the straights pose no problem for the Z to spool up the 18” wheel & tire just as fast as the 17” wheel & tire.

- When the rear was 0.5” lower it seemed that the balance was slightly less optimal than when it was running at the proper height. Weight transfer seemed to be marginally better. There seemed to be more oversteer in the staggered set-up but it never felt like it couldn’t be managed.

There are also some differences that probably contributed to my better lap times today; better familiarity w/ the track, running a lighter fuel load, slightly cooler weather, the quality of the wheels used, but I don’t think either of them or all of them together would have attributed to this much of a difference. So in short; run staggered, not square, at PGP. I know… I know… that should’ve been self evident to me from the beginning. The 17” square set-up has the very distinct advantage in price and selection (about 30% cheaper) and there’s lots threads on the topic as well as guys that’ll swear that the performance difference to price is not worth it. This may hold more true for autoX, but not for PGP and I’m pretty certain not for most tracks.

Talking to one of the guys that has been doing all the PGP events from the beginning who started out on street tires and then moved to R-comps (5 year old V710’s), he found that he was able to gain 3 seconds from his S2K. My thought is the same should hold true for the Z. This is probably the last event I will attend this year but the next one I attend I’ll definitely be running 18” R-comps.

Some of the times by comparison today:
Fasters Production Car (S2k) - 1:13.XX
’09 GT-R (nearly stock) – 1:14.XX
UW Formula SAE – 1:04.XX (possibly a track record)

 

Awesome times man! I love watching that UW Formula SAE rocket around the track I think my Audi is going to be my PGP weapon next year unless I still have the Z.