Jump to content
SAU Community

Circuit Semi Slicks

Roy

By Roy,
in Motorsport Discussion & Builds

 Share

Recommended Posts

SimonR32 Grand Master

SimonR32

Posted
Posted

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?

  • Replies 554
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

hrd-hr30
hrd-hr30

A050 M seem to grip OK even when cold just an excuse to post a pic of the mighty 120Y at Mt Cotton yesterday But they are the grippiest tyre I've ever used.

Snowman
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 int

gtr jet
gtr jet

Do a couple of quick heli's in the closest intersection and then park it back in the garage overnight.

Posted Images

warps Mentor

warps

Posted
Posted

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 Mentor

Victory

Posted
Posted

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.

Duncan Grand Master

Duncan

Posted
Posted

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 Mentor

sweefu

Posted
Posted

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 Grand Master

SimonR32

Posted
Posted

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 Grand Master

Snowman

Posted
Posted

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.

  • Like 3
SimonR32 Grand Master

SimonR32

Posted
Posted

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 Grand Master

Snowman

Posted
Posted

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 Grand Master

Snowman

Posted
Posted

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 Grand Master

hrd-hr30

Posted
Posted (edited)

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 by hrd-hr30
SimonR32 Grand Master

SimonR32

Posted
Posted

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • GTSBoy
      After market rear camber arm adjustment

      By GTSBoy · Posted

      Wheel alignment immediately. Not "when I get around to it". And further to what Duncan said - you cannot just put camber arms on and shorten them. You will introduce bump steer far in excess of what the car had with stock arms. You need adjustable tension arms and they need to be shortened also. The simplest approach is to shorten them the same % as the stock ones. This will not be correct or optimal, but it will be better than any other guess. The correct way to set the lengths of both arms is to use a properly built/set up bump steer gauge and trial and error the adjustments until you hit the camber you need and want and have minimum bump steer in the range of motion that the wheel is expected to travel. And what Duncan said about toe is also very true. And you cannot change the camber arm without also affecting toe. So when you have adjustable arms on the back of a Skyline, the car either needs to go to a talented wheel aligner (not your local tyre shop dropout), or you need to be able to do this stuff yourself at home. Guess which approach I have taken? I have built my own gear for camber, toe and bump steer measurement and I do all this on the flattest bit of concrete I have, with some shims under the tyres on one side to level the car.
    • Jarsky
      R33 Fuel Pump & Brakes after alarm swap

      By Jarsky · Posted

      Thought I would get some advice from others on this situation.    Relevant info: R33 GTS25t Link G4x ECU Walbro 255LPH w/ OEM FP Relay (No relay mod) Scenario: I accidentally messed up my old AVS S5 (rev.1) at the start of the year and the cars been immobilised. Also the siren BBU has completely failed; so I decided to upgrade it.  I got a newer AVS S5 (rev.2?) installed on Friday. The guy removed the old one and its immobilisers. Tried to start it; the car cranks but doesnt start.  The new one was installed and all the alarm functions seem to be working as they should; still wouldn't start Went to bed; got up on Friday morning and decided to have a look into the no start problem. Found the car completely dead.  Charged the battery; plugged it back in and found the brake lights were stuck on.  Unplugging the brake pedal switch the lights turn off. Plug it back in and theyre stuck on again. I tested the switch (continuity test and resistance); all looks good (0-1kohm).  On talking to AVS; found its because of the rubber stopper on the brake pedal; sure enough the middle of it is missing so have ordered a new one. One of those wear items; which was confusing what was going on However when I try unplugging the STOP Light fuses (under the dash and under the hood) the brake light still stays on. Should those fuses not cut the brake light circuit?  I then checked the ECU; FP Speed Error.  Testing the pump again; I can hear the relay clicking every time I switch it to ON. I unplugged the pump and put the multimeter across the plug. No continuity; im seeing 0.6V (ECU signal?) and when it switches the relay I think its like 20mA or 200mA). Not seeing 12.4V / 7-9A. As far as I know; the Fuel Pump was wired through one of the immobiliser relays on the old alarm.  He pulled some thick gauged harness out with the old alarm wiring; which looks to me like it was to bridge connections into the immobilisers? Before it got immobilised it was running just fine.  Im at a loss to why the FP is getting no voltage; I thought maybe the FP was faulty (even though I havent even done 50km on the new pump) but no voltage at the harness plug.  Questions: Could it be he didnt reconnect the fuel pump when testing it after the old alarm removal (before installing the new alarm)?  Is this a case of bridging to the brake lights instead of the fuel pump circuit? It's a bit beyond me as I dont do a lot with electrical; so have tried my best to diagnose what I think seems to make sense.  Seeking advice if theres for sure an issue with the alarm install to get him back here; or if I do infact, need an auto electrician to diagnose it. 
    • Duncan
      After market rear camber arm adjustment

      By Duncan · Posted

      Then, shorten them by 1cm, drop the car back down and have a visual look (or even better, use a spirit level across the wheel to see if you have less camber than before. You still want something like 1.5 for road use. Alternatively, if you have adjustable rear ride height (I assume you do if you have extreme camber wear), raise the suspension back to standard height until you can get it all aligned properly. Finally, keep in mind that wear on the inside of the tyre can be for incorrect toe, not just camber
    • V35Newbie
      After market rear camber arm adjustment

      By V35Newbie · Posted

      I know I have to get a wheel alignment but until then I just need to bring the rear tyres in a bit they're wearing to the belt on the inside and brand new on the outside edge. I did shorten the arms a bit but got it wrong now after a few klms the Slip and VDC lights come on. I'd just like to get it to a point where I can drive for another week or two before getting an alignment. I've had to pay a lot of other stuff recently so doing it myself is my only option 
    • Duncan
      After market rear camber arm adjustment

      By Duncan · Posted

      You just need a wheel alignment after, so just set them to the same as current and drive to the shop. As there are 2 upper links it may also be worth adding adjustable upper front links at the same time; these reduce bump steer when you move the camber (note that setting those correctly takes a lot longer as you have to recheck the camber at each length of the toe arm, through a range of movement, so you could just ignore that unless the handling becomes unpredictable)
×
×
  • Create New...