Optimal wheel and tire size?
 

I plan on taking this car to the track soon, I have stock wheels on atm, plan on buying a new set with rubber!

I read that the PSS would be great tires,

as for wheel, and tire size what's optimal for track on na power?
my friend has 305,17,45 (if I remember correctly.) on his Z, felt a bit heavy,
would the amount of rubber justify the wider wheels (heavier) and the grip?

Pilot Super Sport is a great tire, for street use, but not so much for track duty. If you had to stick with Michelin, try the Pilot Sport Cup for road course instead (assuming that when you mentioned "track", you meant asphalt road course and not autox and not drag racing).

What optimal is difficult to say. Optimal in what sense? Cost, grip, longevity, availability?

First starting out. The PSS's will work for you, BUT once you start getting some track time. The PSS's will get greasy at around the 20 minute if you are really pushing hard. The RE11's will let you go longer and they have a bit more grip. The Mich Cup tires are great, but are $$$. As for tire sizes. A lot of guys run a 18" square set-up.

Read this.

http://www.the370z.com/track-autocro...must-read.html

Thanks for the tire suggestions guys, I'm now wondering what's the optimal wheel and tire size for track? I want grip but I don't want too big of tires to make the car feel heavy

The best streetable options for track use today are the Bridgestone RE-71R and the Nitto NT01. Andrie Hartanto conducted a review and found them to be largely equivalent on the track:

Bridgestone

Both options should last you about 6 standard HPDE days, maybe more if you aren't pushing them. The NT01's aren't so streetable due to issues with heat cycling, so I don't recommend them if you only have one set of wheels. On the other hand, you can typically get a set of four 18" NT01s for ~$900 versus $1100-1200 for the RE-71R.

No one here will be able to tell you what will feel heavy to you. That is extremely personal. You will have to spend money or bum rides from people to find the optimal size for your car and driving style.

Most people start by going square 275. I have never seen 17's fitted to a 370 so 18 would be the next best bet. If you go 18, the two realistic size options you will have are:
275/40/18 & 275/35/18

The 40 aspect ratio will allow you to maintain factory gearing, however tire options may be limited. It will also be heavier and have a bit more sidewall compliance which is not necessarily a bad thing when you are learning how to drive your car.

The 35 aspect ratio has many more choices for tires. Virtually all the hot extreme summer tires (which are the only group of street worth talking about as far as track driving goes) are available as well as a healthy selection of r compounds. You should only look into a set of r-comps once you have a decent amount of experience driving your car in track conditions.

What are the risks / issues with running a 275/35 which is 1" shorter than stock diameter on track days? To the OP point...limited variety in the 275/40 size...and may be forced to 275/35.

shorter gearing meaning you may have to shift a bit sooner and the car will sit a half an inch lower.

Brining back the question....any advantages or disadvantages with running a 275/35/18 which is 1" shorter than stock diameter on track days? Not many options with 275/40/18 that more closely match the stock diameter.

Narrowing in on a dedicated track tire that I can drive to the track 90 - 120 Miles one way
....RE-71. Thoughts?

Ideally as wide as you can, many people prefer a square setup, all 4 the same dimensions. I love the RE-71Rs very grippy but they wear fast, at least that's what people say, I never used another so I can't compare directly.

If I was not competing, I would prioritize longevity and consistency. The re71 are a great tire, but I would go with another 200tw option that would last longer.

I run a set of Hankook Ventus RS4s, in 275/40R18. These seem to prioritize longevity and heat tolerance more than pure grip.

You could also look at the Nexen SUR4G, which seems to an affordable 200TW alternative ($180/tire on Tire Rack). Even if they don't last long, they're still about half the price of an RE71R.

Currently I have Nexen SUR4G 275/40/18, I will get my first real track test for them on Friday. I used RE71R and R888R before and Stones were fantastic, didn't like Toyos.

AIWakRa...thoughts/impressions of the Nexen SUR4G? I am strongly considering this same size over the RE71.

They were fantastic, great grip for the price, and very consistent, they don't lose grip after 2-3 hotlaps like the re71r. Also, they are predictable and easy to control, I like them a lot, as I went for them mainly for the size and stock availability (didn't find rs4 in stock) not price or performance, as any lower sidewall will mean more gear shifts :driving:

You can check this post for videos

http://www.the370z.com/3825587-post165.html