Circuit Semi Slicks

[SimonR32]

I'm still tossing up my next R-comp purchase, have A050 M at the moment in 265/35R18 and thinking of trying out some 295/30R18 if they fit but curious on how the Hankook Z221 perform considering the price, can also get them in a 285/30R18 which may be a happy medium in size.

So in terms of outright lap times, how would a 285 Z221 compare with a 265 A050M?

[warps]

The big feedback I'm hearing from the IPRA guys since going from the 048's to 050's is not only that the grip levels seem much higher, but they maintain the grip almost to the end, and don't seem as bothered by heat cycles. The end result is that many are claiming better value for money as they're getting the full life out of tyres, rather than binning them (selling cheap) after a few heat cycles when there's still a lot of tread left.

Not sure how the Hankooks compare to 048's, but the 050's certainly crap all over the 48's.

[Victory]

A050's do seem to last a lot longer then A048's and still give good grip levels.

I have a good supply of Ao48's from the V9 utes series where teams would only run a set for one round and then off load them as the grip level had gone away. Many of these tyres still have heaps of tread but have lost a few seconds in lap times - but they are great for track days. By comparison the A050's are kept until they are down to the wear indicators as the grip level does not drop off as quickly.

[sweefu]

How would the Z221 store compared to something like A050? My size is 235 45 17 and the Z221 M are $250ea in that size, I can't find A050 for less than $450ea

[Duncan]

How would the Z221 store compared to something like A050? My size is 235 45 17 and the Z221 M are $250ea in that size, I can't find A050 for less than $450ea

That's about right for the price difference.

I haven't run on either but I'd happily take the Hankooks. Yokohama had them banned from Superlap for a reason, and most of the people that buy new Yokos do so because their race rules require thenm.....

[sweefu]

That's about right for the price difference.

I haven't run on either but I'd happily take the Hankooks. Yokohama had them banned from Superlap for a reason, and most of the people that buy new Yokos do so because their race rules require thenm.....

I didn't know that about Superlap, interesting!

For around the $250ea mark the Z221's seem like the best option, that's almost still KU36/RSR etc money.

I went to a track day at Marulan a few weeks ago and a couple of guys there were running them with big praise.

[SimonR32]

How would the Z221 store compared to something like A050? My size is 235 45 17 and the Z221 M are $250ea in that size, I can't find A050 for less than $450ea

Basically the same sort of difference for price in 18's. I don't really mind wear as much as I don't want to go backwards in time.

[Snowman]

I ran on the Hankooks Z221's for the first time recently in my new bus as they are the control tyre for AMCamps.

These weren't the softs that the WTAC guys run. They were the normal compound. One interesting thing I found with them was they really took 3-4 laps to get up to temp and for the times to stabilize. They were a mega tyre for a race though as I was doing 10-12 lap sessions and from lap 4 on wards they were better - but not sure they would be the ideal option if you were only doing 3 lap sprints. As lap 1 was a good +2s slower than lap 4.

As an example here was one of the sessions I did at Winton. You can see the fastest lap was lap 7 and then it was pretty consistent after that.

1. 1:37.6933

2. 1:36.9572

3. 1:36.4395

4. 1:35.6922

5. 1:35.5647

6. 1:35.2582

7. 1:34.7901

8. 1:35.1124

9. 1:35.4962

10. 1:35.2636

11. 1:35.1733

My experience with A050's however is their best lap is lap 1.

[gtr jet]

Shit that's quick.

[SimonR32]

I ran on the Hankooks Z221's for the first time recently in my new bus as they are the control tyre for AMCamps.

These weren't the softs that the WTAC guys run. They were the normal compound. One interesting thing I found with them was they really took 3-4 laps to get up to temp and for the times to stabilize. They were a mega tyre for a race though as I was doing 10-12 lap sessions and from lap 4 on wards they were better - but not sure they would be the ideal option if you were only doing 3 lap sprints. As lap 1 was a good +2s slower than lap 4.

As an example here was one of the sessions I did at Winton. You can see the fastest lap was lap 7 and then it was pretty consistent after that.

1. 1:37.6933

2. 1:36.9572

3. 1:36.4395

4. 1:35.6922

5. 1:35.5647

6. 1:35.2582

7. 1:34.7901

8. 1:35.1124

9. 1:35.4962

10. 1:35.2636

11. 1:35.1733

My experience with A050's however is their best lap is lap 1.

Great info, from what others have said the Hankook soft is more like the A050 medium so I wonder if that makes a difference. Do you have times on a A050 to compare?

I tend to get my best lap on medium A050 on the 3rd hot lap, don't know if it comes down the driving style, tyre pressures or something else

[Snowman]

No I don't have A050 data with this car. That was the first (and only) time I have driven it to date.

But I doubt the Hankook softs are like the A050 Mediums. The softs seem pretty special judging by what we've seen at WTAC.

I just checked and I was running the Hankook Mediums. As you say it may come down to tyre temps/pressures. We were aiming for 34 hot but that was after 10 laps, not 3. Maybe higher starting pressures would yield better results for early laps - I'm not 100% sure TBH. I just know I struggled to get them to "turn on" in the early laps each time out.

[Snowman]

But I will also say the tyres I used had already done a 4hr race at QR and then I did a bit over 50 laps of Winton (just over 150km's) and they were still in pretty damn good condition so they certainly seem to wear well.

[hrd-hr30]

Hankook mediums are the wrong compound choice for sprints. Not fair to compare those to A050 Mediums - the comparable Hankook compound is C70 Soft. Edited this earlier quote to make it a bit clearer:

I learnt the hard way. Bought a pair of bargain secondhand 275 Z214 C51 "Mediums" for the back of the Soarer, only to find they were harder and less grippy than the 245 NT01s I had on there. I had NFI about the Hankook compounds at the time, but "medium" sounded like what I wanted for sprints. Wrong! They're not that old and had almost new tread, so at first I thought they might just have been cooked or heat cycled too many times. But a mate who runs C70s told me about the compounds... At least it was only $100 bucks wasted.

Then I bumped into the Hankook rep up here at a hillclimb and he explained the C70 "softs" as really being medium compound and the C50 "medium" is really a hard compound. C90 (supersoft) for Hillclimbs/WTAC. C70 (soft) for Sprints and short races. C50 (medium) if you want to do a 3hr race!

Edited July 16, 2015 by hrd-hr30

[Snowman]

Yep ok - my experience was with the C5's (C50).

Great tyre for racing but as I suggested not for sprints. Harry's info confirms my thoughts.

[SimonR32]

Found this which is interesting

Have used RE55S, A050-M and Z221 C70 (soft). Z221s are awesome. Compared to A050 the difference in lap time so far has been around 2 seconds, but there's more in them, just have to get used to the grip. Though I have gone from 255/40/17 and 265/35/18 in A050-Medium compound to 265/35/18 and 285/30/18 Z221 soft so it's not a like-for-like comparison. In terms of actually driving the car there is less understeer, but when the car does understeer you still get better cornering ability compared to A050. Finally the Z221s seem to be able to be bullied a bit more. I pretty much killed a fresh set of A050-M at Winton by pushing too hard into the hairpins but with the Z221 you can push and they won't chunk out.

In terms of size, the future is 285-square or GTFO...

RB is right you have about 3 optimal laps then the grip starts to slide off, my car is generally only good for 3-4 laps anyway before it starts to get a little hot so for me the soft compound is perfect.

[fatz]

For the hand cock softs I would run 4 degrees in a gtr

Mine is set up soft and flogs out the corners at 3 so bumping it up to 4 for the next day

[hrd-hr30]

Found this which is interesting

From the sounds of that (around 2sec faster and only 3 laps before they go off), he's almost certainly talking about the C90 supersoft compound.

[SimonR32]

I don't think I'm going to go backwards going a Advan A050 M in 265/35 to a Hankook C70 "Soft" on 285/35 so may just give them a try. I'm also doing a lot of sprint events so the softer compound should come on quicker for these

[Ke55pig]

Has anyone gave the nankang ns2r and the kenda kr20 semis a proper run for there money ?

[sweefu]

Has anyone gave the nankang ns2r and the kenda kr20 semis a proper run for there money ?

I tried NS2-R, very little grip and tore apart on a ripple strip. Not even in the league of Federal RS-R, let alone a proper semi slick.