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I think I’m going mad but I can’t find r spec tyres in 245x40x17 size anywhere in Aus.(can’t afford AO50’s)

I’ve sold my 16x6.5 rims and want a wheel/tyre set up that can optimise the power increase from my upcoming 2.5 swap.

Below is some of my thinking:
I’ve been looking for a lightweight 17x9 rim and can’t seem to get past the RPF1 for weight/value. So if that’s my rim then I’m looking at a 245 width. The original size is 205x45x17 and having just put in a 4.1 diff I don’t want to go for a larger diameter combo and give up acceleration. So 245x40x17 is almost the same.
Nankang AR1 ‘s come in the right size but I can’t find anywhere that sells them!

So, what do the collective use on their NC’s for track work?

Ill ask Ken what these cost, 8 showed up at my shop a few days ago.



255/40/r17 AD08r. It's a lot of rubber, it's a big tyre. The lad holding it is 6'1 and 110kg.

Dann

You won’t need 9” runs for the 2.5’s power. 8” will be plenty, also there is a lot more R Spec tyre choice

I went with the RX7 Wheel which is 16x8 and fitted 225/45/16. This is basically the same diameter as the factory size.
I won't mention what rubber I chose but my pockets were much lighter for my choice.

I am also looking into this soon. 17x9 Enkies seem the go. Tyre choices are limited in 16' or 17's in the correct size I would imagine. 16x9's are probably hard to get too?

$3045 delivered for 8 tyres from Gordon Leven Motorsport. 255/40r17 ad08r x8.

Dann

NitroDann wrote:$3045 delivered for 8 tyres from Gordon Leven Motorsport. 255/40r17 ad08r x8.

Dann

Thanks. They seem value.

Regie wrote:You won’t need 9” runs for the 2.5’s power. 8” will be plenty, also there is a lot more R Spec tyre choice

I know this is ridiculously shallow but the 8” RPF1’s just aren’t as cool as the 9” plus I’m planning a wee bit of Forced Induction

If anyone is interested, I have a pair of RPF1 in black, 17x9 +45 I’m looking to offload.

The inner lip of the rim has a scratch around it as it made contact with something at full lock. Currently has 245/45 17 A050 on them with only 1 track day (as do the rims).

I bought them for my DC2R and realise I should have gotten 22 offset.

Quick update, thanks for everyone’s input.
I’ve pulled the trigger on the 17x9 RPF1’s and gone with a set of 235 40 17 NT01’s. Looking at the tyre size they will be a good fit on the RPF1 9” rim.

Yoko A008’s were $150 a tyre more and I believe are a fair bit slower.
Khumo V70a were $200 a tyre more but slightly faster?
Toyo R888R was also $150 more which is wierd as usually they are v. similar and I believe they own Nitto.
Nankang AR1 was the same price, I could’ve gone with this option and been pretty happy.

I guess you have confirmed that the NT01s are legal under your tech regs? They have been ruled out of Supersprints in NSW so it would be worth checking if you need a tyre that is in Schedule E (CAMS list of 'road tyres'). Earlier discussion here.

I have just tried to link the CAMS Schedule E but that page seems to be down.

I’m just doing club sprints and localish hillclimbs so should be good. Hoping to have the wheels/tyres in time for the next club sprint at QR in September.

For those that haven’t seen them, here’s the wheel/tyre combo. I can confirm they are way too much tyre for standard power.

NitroDann wrote:$3045 delivered for 8 tyres from Gordon Leven Motorsport. 255/40r17 ad08r x8.

Dann

Sorry to bump this thread with no real input, but I was just shocked that those tyres were $380 each! Been a long time since I've bought 17" track tyres, but it makes my 205/50/15 AD08Rs at $189 each seem cheap.

Just seen this reply:

Custardtart wrote:I’m just doing club sprints and localish hillclimbs so should be good. Hoping to have the wheels/tyres in time for the next club sprint at QR in September.

I know people in the 'deep north' like to do things their way, but just about ANY event (as opposed to open track days, test days and the like) will have some form of tech regs/sup regs.

You have bought the tyres, and apparently run with them, but for the benefit of others reading this and asking the same question, "should be good" doesn't cut it at scrutineering. Read the regs, talk to people who run where you want to run, before you spend the money.

Don't be that person who doesn't read the regs, and turns up with car that doesn't comply, or doesn't comply for the class they want to run in.

/sermon.