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I went to Titan Motorsports in Orlando last week to get some servicing done to my Lexus since I'm getting the car prepped for a track day in December. They had their infamous drag Supra in the showroom as well as a R8 V10 with a supercharger for sale. I also saw a very clean Supra in the parking lot that made me want to jump back to getting another MKIV Supra.
I'm scheduled to have my rear fenders pulled next week by a local shop so I can look into bumping up my tire widths from 245F/265R to 255F/275R. One thing that's been bugging me is that I'll be gaining an additional 2 pounds of unsprung weight per wheel for an additional 10mm of tread per tire. I'm not yet convinced that the additional tread is worth the weight penalty.
On the plus side, my overall diameter with the new 255F/275R set-up would be much closer to OEM as my current tire set-up (245F/265R) has the OD 1.35% smaller in the fronts and 2.88% smaller in the rears which is good for acceleration but not good for my odometer as I'm probably gaining an extra 30 miles per 1,000 miles driven.
I think if you could do a square setup with 255/35s all-around, that would be the sweet spot. Plus having the added bonus of being able to rotate all tires would be awesome! As long as you're sticking with MAX summer tires, I think at the power levels we put out, anything larger is unnecessary. What new tires are you considering? I think you'd agree the key for the best handling with our cars is getting the biggest contact patch up front that we can...and you're well on your way there.
Have you thought of installing ARP wheel studs and installing some hubcentric spacers to help "push" out the wheels as far as possible?
Rotating tires would be a big plus but unfortunately my front and rear wheels have different specs (F=18x8.5+35; R=18x9+35). I haven't thought about utilizing aftermarket studs or spacers but I know that for the front, I'll be pushing the tires to the very edge of the fender lip with 255 tires. The rear tires won't be as close to the edge of the fender but with a 275 tire, it will very likely require a fender roll (which I'm scheduled to have next Friday).
I think the 275s on the rear would be very beneficial to my car's set-up since I use the OS Giken TCD to throttle-steer out of corners and the additional contact patch in the rear would help keep the tires from being overloaded too soon. You can kinda see in some of these pics where the load is on the outer rear tire and the OS Giken differential can greatly help apply the power to that tire and get me to the next part of the track sooner:
Meh, I'd still run the 255s despite the SLIGHT wheel width difference.
You're probably right about the fronts (with a 255 tire) would not even be able to fit a spacer AND still fit in the fender wells, even with a roll. And your probably in that same boat with that 275s out back.
Let us know how the "roll" goes and what tire setup you end up going with!
You're probably right about the fronts (with a 255 tire) would not even be able to fit a spacer AND still fit in the fender wells, even with a roll. And your probably in that same boat with that 275s out back.
My front spec is 18x9 +45 PF01's with a 255/35/18 tire and a +5 mm spacer. It's fairly flush and doesn't rub under heavy cornering and braking. Front fenders are rolled.
Over the weekend, I took my IS350 to Stance Garage in Central Florida to get my rear fenders rolled. I'm now ready to switch to a 255F/275R set-up once my existing tires are worn out.
I also picked up a new SA2015 helmet to replace my old helmet so I can be compliant with safety regulations at future track events. This helmet should be good for another decade!
Nice! Let us know what tires you end up going with.
True CF helmet or hydro-dipped or CF vinyl-wrapped? So the newest helmets are good at least for the next 10yrs? I've been holding back getting one thinking the regulations are updated much sooner than every 10 yrs.
The new helmet has a clear-coated carbon fiber graphic. A true CF helmet would easily be double the price!
Yeah, typically Snell ratings are updated every five years (SA2005/SA2010/SA2015) and from what I understand, many tracks won't permit the use of helmets that have a Snell rating that's over 10 years old (e.g. SA2005).
^Thanks Red! That makes sense. The last time I wanted to visit and race on Road Atlanta, they mentioned having to have a certain helmet. The helmet was as much as the track day. LOL! I of course waited.
^Thanks Red! That makes sense. The last time I wanted to visit and race on Road Atlanta, they mentioned having to have a certain helmet. The helmet was as much as the track day. LOL! I of course waited.
If you don't have any plans the weekend of December 10th, feel free to join me and a bunch of IS-F owners in northern Florida for an open track day at The FIRM. Entry fee is only $106 if it's your first time at this track. Just get yourself a new helmet (or rent one at the facility) and make the six hour drive from your location for some fun on the road course.
I just came back from a day of racing at "The FIRM" and I can safely say that the 2GR-FSE and the transmission can safely handle multiple 20 minute sessions on the track at a rev limit of 7200rpm. Powerband was linear and strong at all rpms.
After letting my buddy pass in his 505 HP 2015 Z28 (midway in the video), I tried keeping up with him but even with a tune, his car left me on the straightaways.
I never changed the transmission fluid but I do continously monitor those threads to see if it's truly necessary or not. I think I read that you plan on doing it yourself soon?
I was still running my worn 245F/265R PSS tires but surprisingly, after a total of 40 minutes of track abuse, I only burned off 1/32 of tire tread and that was only on the front tire inner treads. I guess my plans for swapping to a 255F/275R setup will continue to wait...
Yes, that Z28 is driving by one of my track buddies and he's very fast around a track, even without something like a Z28. We both did learn that while the z28 is mostly a track-prepped street car, it has one surprising omission from the factory. While lots of street driven track cars like to use DOT 4 higher boiling point brake fluid, the z28 comes with the same DOT 3 brake fluid found on the base camaros! My friend in the z28 quickly boiled his brake fluids on the track and was forced to call it quits early.
I never changed the transmission fluid but I do continously monitor those threads to see if it's truly necessary or not. I think I read that you plan on doing it yourself soon?
I was still running my worn 245F/265R PSS tires but surprisingly, after a total of 40 minutes of track abuse, I only burned off 1/32 of tire tread and that was only on the front tire inner treads. I guess my plans for swapping to a 255F/275R setup will continue to wait...
Yes, that Z28 is driving by one of my track buddies and he's very fast around a track, even without something like a Z28. We both did learn that while the z28 is mostly a track-prepped street car, it has one surprising omission from the factory. While lots of street driven track cars like to use DOT 4 higher boiling point brake fluid, the z28 comes with the same DOT 3 brake fluid found on the base camaros! My friend in the z28 quickly boiled his brake fluids on the track and was forced to call it quits early.
Put it this way, I have a 70k mile 06' IS350, the previous owner was a older lady, I decided to do a drain and refill (ATS WS 2.5 ish) quarts. The fluid that came out was disgusting, I'm doing a drain and refill with every oil change from now on. I also noticed our transmissions have a filter as well, I'm ordering one soon and plan on dropping the pan to replace.
10-20-16, 11:06 AM
