TAKA 八仔ブログ: Track blogs

Back to skid/drive school....

Wed, 14 May 2008 09:00:29 GMT

I decided that it is time to go back to basic and I think I am losing touch with my driving. Perhaps I have gained some bad habit during the last year or so.

One thing I found after the crash is that I have phobia of spinning. So I think it is worthwhile to learn some car control

Kevin is kindly arranged for us to have the skid pan at Atwood again. So I take the first lesson before the exam.

The problem with the car is that there is too much grip! The positive caster bring the car straight very easily and it is hard when the rear tyre has so much grip comparing the front, so the car is very understeery. But when it is on the skid the car is very controllable and you have to really step the gas to bring the car around. When the car is on the less oily section ... the car brings back quickly and it is hard to adjust the power to keep the skid going. I have too much to learn there.

I learnt very quickly that when just leaving the hand loose on the steering, the caster will pretty much bring the car forward and to the opposite lock. Perfect for track, not so great for skid pan haha.

(Thanks Daniel from shotatcloserange.com for the photos)

Is that the right way to keep the tyre fresh

Sat, 13 Oct 2007 07:31:32 GMT

Glad wrapped!

My theory is to keep the moisture in the tyre, preventing your tyre to dry out.

Place your theory!

Yokohama A048 Review

Sat, 13 Oct 2007 06:57:15 GMT

Now I will lay my opinion of the Yokohama A048. There is no one in the internet writing about this tyres, when comparing this to another brand of S tyres (semi slicks). I have seen a few reports on the A048 when it compares with the new A050 on the circuit driving. Most of the review in Japanese and English, are the people who previously own road tyres. Not a true opinion.

I have met a lot of people who use the same brand of S tyres for years, until they stop production (for example, one person move from Bridgestone RE55S from 540S because they don't make 540S in his size anymore. People are actually scared of changing since there is a need of adjust to the driving line (even your racing lines), your set up, and tyre pressure for a new sets of tyres.

For the people who does not know I used to own a few sets of Bridgestone RE55s SR2 compound in 245/40 R18. I just want to see what other alternatives are there. These are Yokohama A048 M/H compound 235/40 R18.

Here is my comparisons between Bridgestone and Yokohama at Winton Raceway, Victoria:

The ultimate grip is very similar. I will give Yokohama a slight edge there.
Stopping grip is much much better in the Bridgestone.
The cold tyre grip is great in the Yokohama, far consistent through out a 10 lap session too.
Yokohama is very sensitive with high tyre pressure. The difference between 33 psi warm and 37 psi warm is enormous in the Yokohama compare with Bridgestone. I think the best operating temperature is probably in the 31-32 psi warm. The heat disspiate quickly and when I got back to pits. The tyre pressure is in the high 50s, rather than 60s in the Bridgestones.
The control is far more forgiving and feedback is great in the Yokohama. Bridgestone can snap anytime while you can easy driving 8/10th of the tyre grip in the Yokohama.
Tyre wear is moderate on the Yokohama. It certainly are wearing nicely with my current set up. I may want a little more lean on the car (raise the car more) to get the wearing patch right in the middle of the tyre. It is about 3-5mm towards the inside at the moment.

I believe the Yoko A048 has its potential, once I work out the suspension/alignment set up and the correct tyre temp and pressure for these tyres. It is truely a learning experience so far.

Mazda RX-8 Nationals 2007

Sat, 13 Oct 2007 06:10:33 GMT

It was not the perfect day for me. I had been struggling with my step up during the day. The event itself was perfect.

We arrived at the Leisure park on Friday afternoon. There were plenty to do in Benalla (NOT)! So we went out to the race track very quicky and inspected the track. It looked good, although some open wheel Ford went out at the roll over corner.

After Phillip Island mishap, I was very cautious of what I was doing. I had to make sure everything in the car was right. So much so that I misplaced my phone, then my wallet, and had to chase around for it. I knew my mind was wrong.

Rain fell in the middle of Friday night but the weather was perfect for the track day. The air temperature is about 20 degree but the track temp is much lower. Wish the track was much colder since most people were struggling in the morning. I, however, had a much longer task getting the balance right. I will tell you what the problem is later on.

No mishap for today thank god, because I was driving well within myself. Still manage a 1:42.1. I got to be happy with that.

This track day will be my last for 2007. I have decided to have lots of rest and clear my mind for the track days in 2008. I will crack 1:40s in 2008 or I will stop tracking (maybe )

More photos for the day
http://s97.photobucket.com/albums/l230/taka_rx8/The%20Nats%202007/?start=all

Phillip island video

Fri, 28 Sep 2007 05:29:55 GMT

This is the fastest lap of the meet. No you will not see the crash video - too painful to edit and cut! At the end of the year perhaps.

It has to be done... the Phillip Island curse

Tue, 11 Sep 2007 12:56:54 GMT

Well. It was too painful to write it. Even painful enough just to think, but after a few days of claiming down most of the stuff is resolved and parts are ordered. Yes, the ride is crashed. Well I now remembered (after reviewing the video) that I went really really wide in the southern loop that my rear right was touching the gravel and spun.

The result is this.

Here is the damage and what survived:

Front bumper needs to be replaced.
Left front fog light bracket is done but the light itself is working, even the light bulb survives!
Oil cooler is squashed and need to be replaced (ouch!)
The grills and everything else are ok.
Rear right underguard (where the side skirt is) is dented.
The right rear toe and caster arms were bent.
The right rear wheel is off circle a little (will be repaired) and a spare has been purchased.
All tyres are ok.
All brakes and wheel needs to be cleaned.

On the upside I did a 1'59"86. Link here

The circuit is fast and grippy, way too fast and way too grippy in my opinion. It has created some false sense of security and a mad rush of adrenalin. You can take a bend with full throttle at 4gh gear is very addictive. It is so nerve wrecking (what a wrong word to use here ) that one of these fear or thrill will actual give you endorphin to your brain, creating such an euphoria.

I have the video, which I am not prepare to watch too many time and show someone yet. Fuck I should just DivX it and put the unedited version up.

Even better post on the A050 (comparo with A048)

Wed, 05 Sep 2007 02:00:18 GMT

048と比べた印象
１．蛇角を入れてもA048ほどフロントは引っ張らない。
２．ブレーキング時の安定感、縦のトラクション共にA048より上
３．冷えている時のグリップ感もA048より上
４．耐摩耗性もA048より上
５．フィーリングは・・・？慣れの問題か？

That means, the hairpin A048 pushes less, braking is more stable in A050, it works better in cool temp and last longer.

It is less sensitive to air pressure too.

More here

RaceChrono - A GPS smartphone program. Cheap and useful

Sun, 02 Sep 2007 12:11:45 GMT

Well it is free. And I am going to have it "test run" next Saturday during my first Philip Island. It needs a bluetooth GPS receiver and the program is free to download. It is developed by a few track nuts and IT guru in Finland and I am sure they have done some great stuff.

Here is the lap times from my around the lab run. Haha .

This is the map around the block, with the start/finish line and S1 being set on the route (in the car). However, I found out later at home that I can set another trap when the session is finished. See the mark I set at S2. When the new trap S2 is set. I can even get a sector time from that. I can also delete any trap I previously set. So I think when I am out of the course for the first time. I can go back to the pits to set them out and match them with the official map

As you can see here. I set the cursor over in that. Press the ENTER button to go to this screen, and if I select the "Add trap to this" function. It will add me another trap.

Let me try this cf my AIMS unit on Saturday. fun!

Sandown + rain = no fun

Tue, 12 Jun 2007 11:21:04 GMT

There is nothing good or positive that I can say about today. Wet Sandown bitumen is very challenging and in fact it is not much fun when you have to struggle. I think there was something to do with the old technology layout and the tree on the side of the track. The worst thing is most of the exit of the corner is shaded by them. It is more so on the exit of turn 4. While the rest of the track was dry, exit of turn 4 and the Dandenong corner was still way too wet. The worst is the uneven wet and dry line on the road. When the mid corner is wet, there is no way you get any rhythm.

My first session was in the wet, reflected by the shit times. It gradually dried out through out the day. But you can see, the time did not drop to reasonable levels until the late morning.

The first dry session is not perfect, there were still dirt and crap on the road from the rain and all the rubber on the track has been washed off. I could not trust myself to go all 9/10th on a corner. I had turned the DSC off once during the day to make some good run. I guess I am happy with the 1"31.73.

Here is the video

Down to 2 choices

Sun, 27 May 2007 05:19:41 GMT

Yokohama A048 VS Bridgestone RE55s

Some driver of a Lotus Exege in Japan written a wonderful blog on it. I grab the best part of it

５５Ｓの秘めたるパワーとは・・・それは縦方向のグリップ力である。技術論については情報不足でご免なさいなのであるが、０４８は縦横どちらかといえば横方向のグリップ力に勝り、５５Ｓは縦方向へのグリップ力に勝ると言われる。

サーキットとすてきなクルマ＆仲間たち - HAL ! 【みんカラ】ブログ

That translate to the 55S secret is on its power related,... as the longitudinal forces/grip is far more superior. And the 048 has a better balance on transverse and longitudinal grip but the transverse grip is far superior.

Then I interpret it as that....

A048 has more transverse grip, faster corner speed.
But RE55s may have better stopping power.
Putting power is combination of both directions of grip so I think they may be the same.
So if I have new pads than it is ok right? Also I will be racing in Winton for the Nats, which the new slicks are for.
Winton is far easy on brakes than another other track I have ever been.

I think I am very much leaning towards A048.... decision decision!

Two track day for the price of one

Mon, 14 May 2007 14:32:34 GMT

We went to Broadford motorcycle complex to have a track day with driverdynamics. It is a well run day. Kevin brought the rain with them in the morning and we have quite a good sliding run. Then the sun dried the track completely to have the best run of the day for me. I did a 1"09.83 which is 0.57 up from my best last time. I, in fact, did 2 laps of 1.09 which is amazing. There are improvement to be make... like putting a tubro kit in. (just kidding)

Lucky I have alignment done

Fri, 11 May 2007 00:12:19 GMT

Otherwise, I will destroy the new semi slicks that I have. This is what I got from Stuckey when the machine was applied to check the alignment.

The camber was wrong, the front toe was in, and the rear toe is way in (a massive +8.10). It is either a mistake from the last place I went to ... which I suspect since they use a different units of measuring toe (in terms of degree in Centerline). So I think I will stick with Stucky .

I want to max as such in the front as possible. By that the best is to have a person to sit it and balance it out. Adrian muck around a little bit with that and got some since balance with front camber at 2'40" (or 2.6 degree) This seems to be the maximum I could get from the front and that is what I get from Donnellans. Since that time, the car has been handling well and I ain't changing that.

The rear camber is fine since it is slightly less than the front, so I left that.

There has been a big big big push of all four toe zero set up for track use. And slight toe in for the rear for street use (*reference REVspeed May 2007). But I am very conservative on that view and certainly I have tried front toe zero with no great result. The car unwind great but the turn in was horrible. You probably sacrificed the turn in ability with the response of unwinding the car and be more responsive on twisties... But I am willing to get towards zero as much as possible. So I get 1m (toe out) in the front and -2m (toe in) in the rear. That will be a great experiment since my driving has changed so much in the last year.

Monday is Broadford day. I will give it a go. I need a break from work and study now since I am very depressed by it.

Coffee is great at the car wash

Track review of the Ogura Clutch

Mon, 16 Apr 2007 12:43:28 GMT

I cannot hold it anymore.

Another best time

For where the split beacons are LINK TO PIC.

Natsoft data
http://www.natsoft.com.au/cgi-bin/results.cgi?16/04/2007.WIN.P1

Mylaps.com data
http://i97.photobucket.com/albums/l230/taka_rx8/ee5c9fa3.jpg

The car revs very well. I got an extra gear out of the cleevage and to the left turn 10. The gear box is silky smooth and I thought I have not been into the gear. So easy to get into 3rd now! . I think the worn out clutch was the cause of the crunchiness of the gear change on track. Now sorted.

I got a PB on the set up lap with a passenger inside. What the hell. I knew I have something special today. The car is AOK for balance with the new found power. At the straight I got another 5kmh .

Look at my theoratical best time. .... 1.41.420.

The midpipe popped out in the last session and melted the bumper guard .

Imitation Stig completed

Fri, 02 Mar 2007 13:27:32 GMT

Try them on today.

Thought the gloves are too large, but I think now it is more comfortable for long drive if it is slightly loose.

What do you think?

Please place comment!

Track Scheudle 2007

Sun, 31 Dec 2006 14:14:15 GMT

~~Jan 26 - Winton Test and Tune day.~~ 1'43.146 (blog)

~~March 11 - OzRenesis Winton Track day.~~ 1'42.3920 (blog)

~~April 16 - EXE club Winton Track day.~~ 1'41.8660 (blog)

~~May 14 - OzRenesis Broadford Track/Driver Education day~~. 1'09.83 (blog)

~~June 11 - On the run motorsport Winton Track day. (not running)~~

~~June 12 - DriverDynamics Sandown Track/Driver Education day.~~ Wet! 1'31.73 (blog)

~~Aug 20 - OzRenesis Winton Pre Nats Practice? (cancelled)~~

~~Sept 8 - AROCA Philip Island Sprint day (crashed).~~

~~Sept 30 - EXE Winton track day *(did not run).~~

~~Oct 6 - 2007 RX-8 National (Winton) -~~ 1'42.13.

~~Nov 5 - Sandown, DriverDyamics~~.

~~Nov 18 - Honda Sport Car Club Winton Track Day. (Not running since I will be in Macau)~~

~~December 10 - DriverDyamics Broadford track day (not running)~~

~~December 16 - AROCA Philip Island Sprint day (not running)~~

My personal best lap record

Wed, 30 Nov 2005 14:45:43 GMT

Winton Raceway - Benalla, VIC
1'41.8660 (EXE Club day - 16.4.2007)

Sandown International Raceway - Springvale VIC
1'31.73 (DriverDynamics Track day - June 2007)

Broadford Motorcycle Complex - Broadford VIC
1'09.830 (OzRenesis Track day - 14.05.2007)

Phillip Island GP circuit - Philip Island VIC
1'59.8600 (AROCA sprint 08.09.2007)

Wakefield Park - Goulburn NSW
1'14.8630 (2005 RX-8 Nationals)