Square Setup 18"
Not spacers. You're stuck with an extra 10mm in front and 20mm in back with those offsets. FYI, the OEM offsets are +45F and +55R for '08 - '11, and +45F and +51R for 2012 and later. All model years use the same hubs, and only the toe link in the rear was changed in 2011 (part numbers changed for most of the rear, but that was because the bushings are different, the toe link is actually not the same length). So, armed with this knowledge, it is very safe to infer a set of wheels with these offsets will work on any model year IS F, and not cause significant suspension issues.
When SCCAForums did this test with an 18" wheel, he said the wheels nearly scraped the Lexus off the calipers. AFAIK from this forum, no one has put on RPF1s and actually driven on them to determine if there is enough caliper clearance in service. Stuff moves and flexes in service, so you want to have at least 6mm clearance from the caliper face or you might very well have wheel to caliper contact under track loads. 4mm might be OK for street, but would be pretty hairball and not worth it if you have less than 4mm. Supras came with 6mm from the factory, and they're pretty tight (don't spin the wheel with your finger in there, it's going to get really hurt).
Driver
Joined: Mar 2016
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From: Ca
When SCCAForums did this test with an 18" wheel, he said the wheels nearly scraped the Lexus off the calipers. AFAIK from this forum, no one has put on RPF1s and actually driven on them to determine if there is enough caliper clearance in service. Stuff moves and flexes in service, so you want to have at least 6mm clearance from the caliper face or you might very well have wheel to caliper contact under track loads. 4mm might be OK for street, but would be pretty hairball and not worth it if you have less than 4mm. Supras came with 6mm from the factory, and they're pretty tight (don't spin the wheel with your finger in there, it's going to get really hurt).
I'll know soon enough what kind of clearance is available on the +38 and +45 versions in 9.5" width, of which I have a pair of each.
Edit: Update from said local friend... He states there is substantial clearance from wheel spokes to caliper, but it's tighter from caliper to the wheel's barrel. The balancing weights must be placed strategically away from the caliper's path to provide proper clearance.
Last edited by Leander311; Jan 9, 2018 at 10:18 AM. Reason: Update
Pit Crew
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From: KS
Looks like 18x10 +38 is the magic number for maximum tire? Would be nice to get back into square wheels and away from 18s.
Is your friend running 275/35/18 r-compounds? Please ask him what his alignment is, too. Pictures would be great.
Is your friend running 275/35/18 r-compounds? Please ask him what his alignment is, too. Pictures would be great.
Instructor
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From: MD
No it most definitely is not the magic number for maximum width (unless you plan to run camber, then IDK). If I had to take a guess for a squared setup, the magic number would likely be a 9.5" wheel with +48 offset all around...maybe even +50 offset. What will determine the maximum tire you can fit for a squared setup is at which point you have too conservative an offset and you start to rub on the inside of the wheel well while turning. With these cars, the farther in you can tuck your wheels/tires, the wider you can go.
See my sizes for 19's... my +40's seem to work really well w/275/30/19's all around. Gymkata notes higher offsets closer to stock, but I also noticed he stated in another thread there is some rear rubbing with them. To be fair, I get the slightest of rubbing on the right/front liner at full left lock, but it's obvious my fender liner is a bit distorted there from a previous accident. Otherwise, I'm completely rub-free, even with 3 passengers and luggage or when tracking hard. See explanation earlier, I also had rear lowered about 1.5" on "accident" during a full day at CoTA and had no rubbing with this combo. I'm at just under 2.5/2.0 degrees camber front/rear.
Also FWIW, here is RR Racing's track setup on TSW Nurburgring's: 18x10 +40 w295/30/18's square
(https://www.clublexus.com/forums/cl-...ml#post9953996)
FIGS' shop IS-F is very similar, and both cars are mildly lowered.
(https://www.clublexus.com/forums/cl-...ml#post9953996)
FIGS' shop IS-F is very similar, and both cars are mildly lowered.
Driver School Candidate
Joined: Apr 2017
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From: Ontario
Also FWIW, here is RR Racing's track setup on TSW Nurburgring's: 18x10 +40 w295/30/18's square
(https://www.clublexus.com/forums/cl-...ml#post9953996)
FIGS' shop IS-F is very similar, and both cars are mildly lowered.
(https://www.clublexus.com/forums/cl-...ml#post9953996)
FIGS' shop IS-F is very similar, and both cars are mildly lowered.
-Mike
There are a lot of wheel manufacturers out there, and it's been a while since I looked at wheels. Below are just a few possibilities you could look into.
WedsSport:
SA-10R 18x9.5 +45 - 20.39lb
SA-15R 18X9.5 +48 – approx 20lb
SA-20R 18x9.5 +45 – 19.89lb
SA-72R 18x9.5 +45 – 20.06lb
RN-55M 18x9 +45 - 20.24lb
RN-55M 18x9.5 +45 - 20.77lb
RN-05M 18x9 +43 – 20.31lb
TC-105N 18x9 +50 – 16.94lb
Enkei:
Enkei GTC01 RR 18x9 +40 (approx 19.5lb)
Enkei GTC01 RR 18x9.5 +45 (approx 20lb)
Enkei RS05RR 18x9 +45 (approx 19lb)
Enkei RSM9 18x9 +45 (approx 20lb)
Enkei RSM9 18x9.5 +45 (approx20lb)
Enkei PF07 18x9 +40 (wt unk)
Enkei PF07 18x9.5 +40 (wt unk)
Enkei PF01 18x9.5+45 (approx 20lb)
SSR:
SSR GTV02 18x9 +45 (wt unk)
SSR GTV02 18x9.5 +45 (wt unk)
SSR GTV03 18x9.5 +45 (wt unk)
SSR Executor series 2/3 pc wheels – can choose between a wide range of offsets and disks
WedsSport:
SA-10R 18x9.5 +45 - 20.39lb
SA-15R 18X9.5 +48 – approx 20lb
SA-20R 18x9.5 +45 – 19.89lb
SA-72R 18x9.5 +45 – 20.06lb
RN-55M 18x9 +45 - 20.24lb
RN-55M 18x9.5 +45 - 20.77lb
RN-05M 18x9 +43 – 20.31lb
TC-105N 18x9 +50 – 16.94lb
Enkei:
Enkei GTC01 RR 18x9 +40 (approx 19.5lb)
Enkei GTC01 RR 18x9.5 +45 (approx 20lb)
Enkei RS05RR 18x9 +45 (approx 19lb)
Enkei RSM9 18x9 +45 (approx 20lb)
Enkei RSM9 18x9.5 +45 (approx20lb)
Enkei PF07 18x9 +40 (wt unk)
Enkei PF07 18x9.5 +40 (wt unk)
Enkei PF01 18x9.5+45 (approx 20lb)
SSR:
SSR GTV02 18x9 +45 (wt unk)
SSR GTV02 18x9.5 +45 (wt unk)
SSR GTV03 18x9.5 +45 (wt unk)
SSR Executor series 2/3 pc wheels – can choose between a wide range of offsets and disks
Thanks for helping me out.. I got the SA-10R 18x9.5 +38 for my Lexus IS F.
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