Street vs R-spec tyres

[Reedy]

Well I got my first set of Semi Slicks and hit the track a week or so ago, unfortunately the weather sucked on the day but we did get SOME dry running in, even with the track conditions not being ideal I still beat my previous PB by about 1.2 seconds, and I was driving like an absolute mong that day as well, no rhythm at all. I know that I will go a lazy second or so quicker next time I have a run so that gives the Semi Slicks about a 2 second per lap improvement around Wakefield park.

Who else has some data to share from running different tyres? I am interested in gathering more info on the relative performance of running different tyres on the same car. Everyone seems to have an opinion on what is faster out of AD08's, RS-3's and RE-11's but there is very little hard evidence to back any of it I find.

For me it goes something like:
POS Dunlops the car came with: 1:15 (They died this day)
Yokohama AD08 = 1:13.3 (Epic tyres, cannot recommend these highly enough)
Yokohama A050 (Soft) = 1:12.1 (LOTS of room for improvement, I think I could do a low 11 with these)

Scooby (Lakeside):
Federal 595RSR: 59.89
Federal FZ201: 58.64

HRD:
Lakeside old surface JZA80 Supra Federal 595SS 1:03.58
Lakeside old surface JZA80 Supra Kumho KU36 1:01.39

[scooby36]

http://www.youtube.com/watch?v=tm5JmX7Gfrg my video, RSR vs fz201 (+20mm wider so not really a fair comparison) on the same day

[morerevsm3]

soft A050 should be at least 4 seconds a lap quicker than street tyres if suspension is set up to make them work properly

[Reedy]

4 Seconds? Over AD08's or regular street tyres? That's huge.

I know suspension is a real limiting factor on my car, this was clear to me on the day. It is still a street car tho and there is a limit to how far I want to compromise it, it is only a FWD hot hatch after all so i'm not going to pretend it is a full blown race car. I was satisfied enough with going a bit quicker in bad conditions but you've got me thinking I can probably go faster than I thought.

I still have a fairly long way to go as far as driving is concerned as well, only been doing this for the last 12 months.

[jezza323]

from memory i dropped 2 secs at QR first time out on semi slicks (was also only 2nd time out though). i then proceeded to drop another 3 secs off with more practice/tweaks over the following months

[morerevsm3]

4 seconds quicker than AD08s is conservative, your biggest problem will be front tyres will get destroyed very quickly due to lack of neg camber, the soft compound you should only be doing 2 laps at a time too, aim for ~ 28 psi hot

[Reedy]

Yea i've found due to that reason I have had better results running slightly higher front pressures or else the tyres roll onto their sidewall, at least that's what I found with the AD08's.

[333pg333]

Big call going for the softs. But yes, you're suspension will get found out the stickier the tyres you go up to. Those softs will generate approx 1.3 g's which is substantial. This will increase your body roll a lot.
To give you an idea. I went from Nitto NT01s which are a medium compound and had moved up to 800lbf / 900lb rear springs. The car felt taught and tight. Put on some proper slicks and the car instantly felt like a boat. Substantially increased the body roll and that's not on what you'd call soft springs. Moreresm3 is correct about the suspension geometry too. You need to adjust yours to take full advantage of the new tyres, but also not to kill them in a couple hours driving.

[Reedy]

Yea I won $500 to spend on Yokohama gear so went ape on a set of tyres I wouldn't have otherwise bought. Still having some fun with them for the sake of experimentation.

[333pg333]

Thought $500 would get you about 1 tyre?

[Reedy]

Was reason enough for me. Worst I could do is sell them on after a track day or 2 and break even (ish)

I still wanted to give R-specs a try anyway, just another piece in the racing puzzle that I want to understand and learn about first hand, there is so much bad advice out there these days I like to do things for myself where possible.

[333pg333]

R specs are great in my book, but you won't get much life out of those Softs. Next time go mediums and you'll get heaps more out of them over time.
Also, depending on your car, you 'might' have to think about the oiling issue under higher g's that the R specs can bring. Spinning a bearing or worse isn't out of the question.
Probably worth checking with other guys running similar setup to yours. Of course you may already know this so ignore me in that case. Have fun!

[itsnotagsr]

Bear the weight of your car in mind too. I found something like a bug-eye sti destroys mediums pretty easily. If you want your tyres to last, go the hards.

[Reedy]

My AD08s are my long term tyres and they have been great. The softs were just a pure indulgence by me that I bought because I can.

Oiling issues are under control for now, if I start going significantly quicker then things might need addressing but for now I just make sure it's kept brimmed at all times. Other guys who race in production classes don't do anything special with their engines and they go a lot quicker than I do.

[adamRSLC]

Rexies are very good with oil control as they have a pretty nice sump out of the box , womblesti has a heap of experience playing with tyres on his rexie so might be worth a PM for more specific questions .

Adam

[hrd]

I did two days at Lakeside on Federal 595SS (the normal street tyres, not rsr's) on the Supra when the place first re-opened. Then bought a set of KU36s when they first started appearing...

Lakeside old surface JZA80 Supra Federal 595SS 1:03.58
Lakeside old surface JZA80 Supra Kumho KU36 1:01.39

never ran it on proper semis unfortunately.

[spiller]

Just for clarification

Federal RSR, Toyo R88, KU36 and AD08 are street tyres for the basis of this thread yeah?

[Reedy]

R888's I would class as R-spec. Basically anything with a treadwear rating less than 120 is considered R-spec for timeattack events. The others you've listed are all above 120, the soft yokohamas I have don't even have a treadwear rating heh.

[spiller]

what are people's opinions on the hankook ventus semislick? They seem to be all the rage in time attack now. I wish time attack would legalise slicks so i could run on the much more affordable michelin cups. Slicks have been made legal for this years SA time attack but only in the pro class and only if you can go 1.14 or faster around mallala (that's right, you can only use slicks if you are fast enough, which will then make you faster again...wtf).

[Reedy]

You mean the Z221's? At world time attack all of the top competitors were using either those or the Yokohama A050. By the sounds of it they are basically equal as the fastest time attack tyre. Hankook ones seem to be better value tho.

[Chisholm]

IMO/experience limited gain in going R-comps if you don't have a fairly decent suspension setup and alignment (i.e -3 front camber). On off-the-shelf kinglows/KYBs and street alignment R-comps didn't really make me go any faster, just better tyre wear/life than street tyres. But maybe still worth it, running some cheapy used R-comps is better than chewing through street tyres.

With good sussy/setup the difference between R-comps and streets is enormous. Not just in terms of outright PBs, but consistency over laps, wear and feel.

Last time I was out at Wakefield I was into the 1:10s on Kumho V710. 1st session of the day I went out on KU36s for a few laps and didn't go faster than ~1:14s. Yes it was only a few laps getting a feel 1st session out but you get the idea.

[turbosurfer]

When I 1st got my evo I stupidly ran R specs unknowing that you need at minium of 2 degrees of negitive camber
presto 18 laps at 3 laps at a time tyres absolutly destroyed and had to bin them. $1800 down the drain just for the
evo nats wank.OUCH!!!
Now have camber and my car is really gentle on tyre ware last for a dozen supersprint type events.
Camber is a big key with R-specs

[Cracka]

Im surprised how little extra people get out of AD08 and FZ201's vs the RSR for so much more cash. I cant fault the RSR (not on a track) when they have some temp in.

[itsnotagsr]

What are the RSRs like on the street for a limited mileage car?

[Coffin]

Im surprised how little extra people get out of AD08 and FZ201's vs the RSR for so much more cash. I cant fault the RSR (not on a track) when they have some temp in.

Depending on size, the FZ's arent too much more expensive than RSR's

What are the RSRs like on the street for a limited mileage car?

Chris, pretty good, ... I know Farmsci had RSR's on his MY04 WRX, couple track days, few hillclimbs, and daily driver duties and was getting over 15,000k's off them but pretty good times around wakefield and Sutton Road hillclimb too (Faster than me at the moment on both)