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Discussion Starter · #1 ·
I wanted to put together a setup with R compounds for the track using 18" wheels. Reason for 18" wheels was the wide choice of R compounds and much lower cost of the 18" R compounds vs the 19" or even 20" ones.

Here are the things I was considering for my R-compound setup:

1. Not necessarily the fastest track setup, but the most cost effective and still fast setup
2. Reduction of understeer with wider front tires than OEM 255's
3. Identical front and rear tires and wheels to allow swapping them around to optimize wear.
4. Lowered car
5. Identical front and rear diameters to keep diffs happy
6. Quality wheels designed to take the load
7. Good looks

A while back, Sharif tried out the Enkei NT03's and found they didn't come close to fitting in 18". I knew of Volk TE-37's and CCW's C-10's in 18" that fit, but I wanted something less expensive. Since Enkei makes wheels for the McLaren Formula 1 team, I figured they were worth investigating a little more. So I got in touch with King at the US Enkei distributor. He didn't know what fit from their line, so he inquired from the factory in Japan. He forwarded their reply to me in Japanese and translated it to confirm that both the 18" and 19" models of the GTC-01's in 10" width would fit over the brakes front and rear, clear the suspension, and only negative is that wheels stick out further than OEM in front. No one else I talked to seemed to know if they would work out, but I found them on a fire sale so I decided to take the plunge and ordered four.

For tires, I have run a bunch of different ones, and I like Hoosiers and Michelin Pilot sport Cups the best. I have never been a fan of Toyo RA-1's because they are too easy to overheat if they aren't shaved, and if shaved you have wasted money to shave them and taken off a bunch of rubber that reduces their life and makes the other tires I like a better and faster choice. But the Toyo R-888's are out, and an equivalent tire made by their subsidiary in Japan, Nitto NT01 is said to be good with heavy cars. They have wide tread blocks unlike the RA-1's, so much less likely to overheat if not shaved. They happened to make a size that worked out perfectly for my 18x10" wheels, a 275/40/18. This tire is rated for the load of the GT-R, and is quite tall for an 18" at 275/40/18. Outside diameter is specified at 26.65", which is about 1.5" less O.D. than the OEM tires which are around 28". So car is lowered by half that at 0.75" drop, more or less. And they are low cost compared to Hoosiers and Sport Cups, so I fugued I had the tires and the wheels that met all my requirements. I ordered them all together, mounted and balanced, and it has all worked out perfectly. everything clears, and fits, and I think it looks good.

Wheels front and rear are Enkei GTC-01 in 18x10 with 22 offset all around.
Tires front and rear are Nitto NT01 275/40/18

Specified weight of wheel is 24.5 lbs, so not as light as Volk TE-37's, but a ton cheaper. I measured front OEM wheel and tire (255/40/20 on 20x9.5 wheels) at 62.8 lbs, and rear OEM wheel and tire (285/35/20 on 20x10.5 wheels) at 65.6 lbs. My Enkei's with NT01's mounted weigh 52.2 lbs. So total for 4 OEM wheels and tires is 256.8 lbs vs. 208.8 lbs for my track setup. That is a saving of 48 lbs of unsprung and rotational weight, which is a bunch.

Rear tire and wheel combo fits just about the same as OEM, and the fronts stick out a bit past the OEM's. I figure that might be a bonus in reducing understeer as front track is increased which reduces total weight transfer for the car and in particular reduces front weight transfer, thus increasing front grip and reducing understeer. Negative will be increased scrub radius and increased steering effort with less optimal feedback through the steering wheel. I asked King at Enkei if they had 10" wheels with more offset than 22, and he said they did not. It turns out that a 10" wheel with much more offset than 22 would not likely fit due to the clearance with the upper part of the front knuckle. The knuckle starts close to the wheel at the center and curves away from the wheel as it goes up-wards toward the upper A-arm. This means that lower diameter wheels have less clearance than larger diameter wheels. So a 19" in the same width could have more offset than an 18", but less than a 20". The OEM 9.5" wheels have an offset of 45 mm, but that offset would never fit with an 18" wheels in 10" width.

So here are some pictures















I'm anxious for the snow to melt so I can burn them up!
 

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this looks like a great budget setup, good find.

I wonder if the Enkei RPF wheels would be roughtly the same clearance?

 

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Those look nice but I can't wait to see some rpf01's. Problems I see tho is the lower tire size without aftermarket suspension could cause some bumping or scraping maybe. So 28" is idea unless suspension is tweaked to remedy that (if that's the case anyway). The 26.65" might not have any worries tho.
 

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Discussion Starter · #5 ·
Those look nice but I can't wait to see some rpf01's. Problems I see tho is the lower tire size without aftermarket suspension could cause some bumping or scraping maybe. So 28" is idea unless suspension is tweaked to remedy that (if that's the case anyway). The 26.65" might not have any worries tho.
Enkei RFP-1's will not fit in 18". That was the first thing I checked with Enkei USA. There is no suspension issue with running smaller diameter tires, Suspension issues are far more likely with lowered suspension which places suspension away from its design mid-position. This affects camber and toe curves. There is no way an aftermarket suspension is going to improve things unless they start to move the suspension attachment points. Aftermarket suspensions can benefit the car by lowering center of gravity, increasing roll stiffness and improving damping and static camber. But they do this at the expense of wheel travel in bump and less than optimal motion. Gains are usually more than losses due to better control of camber with stiffer springs.

There will likely be many more 20" wheels and R-compounds in the future for the GT-R, but the price is going to be very, very much higher than the setup I have come up with. Tires I am using are in the $250 each range and wheels are in the $400-$450 each range, so about $2600 total. Plus if I want to run Hoosiers or any other tire, I can find many that will fit my wheels, and not have to worry about different diameters. And I consider the possibility of swapping the wheels to any corner a major bonus for evening out tire wear on the track.
 

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Thanks for taking the plunge and trying these out for everyone.

You are probably going to find, you will have too much oversteer with the current stagger...LOL...I know...hard to believe.
A 15-20mm rear spacer will solve that issue are return you to a more neutral balance. I found that a 20mm spacer on my rear really settled the rear end down.

Keep us posted on how they handle. What is the first track you are going to tackle with them?
 

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In terms of 19" fitment of the GTC01's, here is the info I got from Enkei Japan via King Brandt of Enkei USA.

Below chart is for GTR matching information of GTC01.
Caliper X is not applicable (not OK).Outer X is tire is out of fender.
Outer triangle is applicable (OK) but tire outer surface is inside of OE size



So 19x10 22mm would fit identically to the 18x10 22mm I got. However as the front tire sticks out further than OEM, you would have to confirm that tire doesn't rub fender if it has a large diameter than the ones I am running which have a 26.5" measured O.D. 19x9.5 42mm would not stick out, but that defeats my choice of using the same wheels all around.

Interesting info about the spacers for the rear. I may have to invest in some longer studs and add spacers. What wheel nuts do you use to be able to fit OEM wheels back on with the longer studs and no spacers?
 

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In terms of 19" fitment of the GTC01's, here is the info I got from Enkei Japan via King Brandt of Enkei USA.

Below chart is for GTR matching information of GTC01.
Caliper X is not applicable (not OK).Outer X is tire is out of fender.
Outer triangle is applicable (OK) but tire outer surface is inside of OE size



So 19x10 22mm would fit identically to the 18x10 22mm I got. However as the front tire sticks out further than OEM, you would have to confirm that tire doesn't rub fender if it has a large diameter than the ones I am running which have a 26.5" measured O.D. 19x9.5 42mm would not stick out, but that defeats my choice of using the same wheels all around.

Interesting info about the spacers for the rear. I may have to invest in some longer studs and add spacers. What wheel nuts do you use to be able to fit OEM wheels back on with the longer studs and no spacers?
We use extended ARP studs. For lugs, I am using a standard chromoloy steel tuner lugnut open-ended. It has a neochrome finish, but it's essentially a basic extended open-ended racing lugnut. I don't have OEM wheels anymore, so without examining the seat, I can't tell you if the lugs will work for certain. Nissan uses a style of lugnut that I am unfamiliar with. I have used aftermarket lugs on other Nissan wheels without issues, but it would be something I'd like to investigate further.

I do carry the ARP extended studs in stock, if anyone needs them. I change them out once a year on all the cars I track. Havent had a stripped, damaged, or otherwise messed up lugnut or stud yet.
 

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when its time i think ill do the 19" GTC's , wish they came darker though.... wrapped in R888's....
 

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Massive thanks to the OP for trying out these rims,

i managed to get a set this week and paired them up with 295/35 Bridgestone RE55's

Can't wait to try these out next week at the track!

 

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those are pretty and i like that they have the antislip lip like the stockers.... how much would 19" weigh ...? vs stock..?
 

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Discussion Starter · #16 ·

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^ I just got mine off the ups truck and notice the same thing. Two valves!!! Anyway, thank to OP for taking the time to do some leg works for the rest of us enthusiast. I will tried them out next session. Also, I notice the nitto tire come with a warning not to be use on highway? I though they are ZR rated with treadwear 100. Anybody have and opinion about that?
 

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wheel_stud2.jpg wheel_stud.jpg Hi, I ran into a dilema. I got the wheels and tires set up like the OP and I tried to test them on the car. There is an extra protrustion beside the 5 studs. How in the world will the wheel clear this?? This is the front passenger side. Is it the same on all wheel? Can it be trim down? I have add a couple of images for clarification.
 

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