race pace cornering

[NZeder]

The tierod length issue - get some 280zx non power steering tie rods they are 10mm longer than the 240/260z units. However the catch with this is they are only RHT (Right hand thread) and the stock 240/260z racks have a LHT and RHT. I am trying to find a supplier for the inner tierod/rack end as Nissan only have the LHS (Left Hand Side) units which must be purchased with a new outer also. But these are the LHT = ahh no good.

 

I need to do something for my zed as when it was on the road last time the setup was such that the tierod ends were only just on the rack - dangerous so I am hoping to get 2 x RHT on the end of my rack so I can use the 280zx longer tie rods.

 

As the rack ends are proving hard if not impossible to find - I am thinking that I might look at changing racks so a unit that parts are available for - but I want a non powered unit which does not leave much choice in the front mount rack space that is narrow enough for the S30 chassis.

 

Enough of rank about the S30 racks. So I must say good new on the tie rods so you can sleep easy not like me....I keep thinking there has to be a solution to the inner rack end supply issues.

[chev z]

Just a very quick update.

A successful first up trial,in extremely hot conditions that tested both car and driver, we achieved a reduction of 2.7 sec per lap on my previous times.

Consistently lapped in the  1min 47's of the Winton long track.

The larger diameter tyres were a handicap ,just lost to much  acceleration,they also altered the gearing thru corners.Will try set up with 50's, this will give a more accurate evaluation of where I'm at .

Front tyre wear was good and the car definately turned in easier

 

Of course one thing leads to another .

 

I have discovered that in these conditions my brake fluid boils or rotors/ brake pads decide to stop working which leads to interesting exits here and there.Definitely makes driving more exciting, no interesting, no less predictable ....no make that NERVE racking.

 

But the best result of all, is that the re-engineered parts held together

 

[Zedman240®]

Funny you should mention about the brakes...at the last MSCA event we had a club member who is obviously getting better driving around the circuit with R spec rubber and a 3 ltr engine, discovered what "brake fade" is! As you set up your car and find it works better, you tend to push it harder and then you find the limit of the stock brakes...

[xa1973]

The focus of circuit chassis tuning is to remove the compliance from the vehicle, and instead make the shock absorbers and springs do the work of controlling the body.

With this in mind, every litle bit of rubber between the body and the tyres needs to be removed and replaced with solid, metal type mounts.

Many conventional bushes should be replaced with rod end or rose joints.

Removing the flexibility of the car gives the driver a more direct link between the steering wheel and the road, in turn delivering better on the limit control and more accurate use of the tyre rubber, which all adds up to more consistant and higher levels of speed, when set up correctly its easy to see how far removed a road car is from a decent circuit weapon.

 

CIRCUIT SET UP

 

SHOCK ABSORBERS              COIL OVER PLATFORM ADJUSTABLE

SPRINGS                            SINGLE RATE HEAVY

SWAY BARS                        ADJUSTABLE

BODY STIFFENING                INTEGRATED ROLLCAGE

ARMS                                 ROD END JOINTS

RIDE HEIGHT                       MINIMUM TO AVOID BOTTOMING

FRONT                               4* NEGATIVE CAMBER

REAR                                 2.5* NEGATIVE CAMBER

BALANCE                            NEUTRAL

Adjustment of the roll centre and weight distribution of the car can lead to some serious gains in lap speed, optimal camber settings can really only be determined via tyre wear patterns, a vehicle with toe out will turn into corners better, but have less straight line stability.

As with everything its a comprimise, even purpose built big ticket racers have deficiencies, but the methodoligy remains the same 

[C.A.R.]

Tyre wear patterns = tire temps which can only be determined with a pyrometer immediately after a session.

BUT camber adjustment at the track is a PITA with McPherson struts unless you have slotted towers, otherwise if you adjust the camber at the LCA you will then have to make toe changes...

[xa1973]

Tyre wear patterns = tire temps which can only be determined with a pyrometer immediately after a session.

BUT camber adjustment at the track is a PITA with McPherson struts unless you have slotted towers, otherwise if you adjust the camber at the LCA you will then have to make toe changes...

 

Gday Lurch

 

How was WA, I spent the best part of fifteen years in the Pilbara region, now back home in QLD

 

Yes, your quite correct in your follow up, my post is a basic setup for the weekend warrior

 

Cheers

[C.A.R.]

Hey XA,

WA has been good - pity I got here at the wrong time though

I wish I could have gotton a job in the Pilbara, but I guess it wasn't to be...

 

Not a worry mate - I was just being pedantic!

I guess one has to weigh up how serious one wants to get when doing track work,

BUT tire temps are very important in getting the maximum life out of one's tires...

 

[chev z]

I have taken Lurches advice and procured HTX115 brake fluid. It is rated 5.1, this should help with any boiling .Plus have bought some flexiable tubing so I can duct air to the front disc brakes.

 

If I get time next week,I intend to upgrade the front brakes using the tutorial by Lurch as a guide. After comparing the pros and cons between S13 or Peugot rotors I have decided on the Peugot .Less fabrication and they are already slotted.

The difference in cost being only  approx. $20

Found some  S12W Hilux calipers for $80 each at a FWD wreckers.

 

My big stumbling block is trying to find a 280zx brake master cylinder ...CAN ANYONE HELP

 

 

[C.A.R.]

Steve, you can buy them new for around $200.

PM Dimitri (Zedman240) for more info.

[chev z]

Going to Shepparton Tues. , I will try to procure brake master cyl.

 

A change of plans as of this morn. , the Peugot slotted rotors have been revalued at  $260 a pair as opposed to S13 slotted at $210

Apparently forgot to add slotting cost.

Oh well it has been extremely hot up this way ,so brain malfunction malfunction malfunction[lol] can be forgiven.

 

I am thinking of using Lucas brake pads,apparently work well,cheap but dirty...two out of three ain't bad.

Any other pad ideas worth considering?

[C.A.R.]

My preference are Ferodo DS2500's or if you’re really giving your brakes a hard time; DS3000's.

 

 

[chev z]

My apologies to everyone for going of the initial thread.

 

Bloody hell Lurch, your the moderator keep me in line, hang on a minute ....after back tracking thru the posts, I realised your mainly to blame for my errant meanderings.

 

Xa73 has brought up another discussion point, that being the use of neg. camber on the rear wheels.On Friday I will set up front caster between 3 to 4 degrees positive.[ depends on available guard space ]

Also increase the front camber to 3.5 degrees negative. 

 

The proposal of Xa73 to go with 2.5 dgrees of negative camber on the rear has merits ,in that it will increase the amount of tyre contact with the track when cornering, but will this setup  negate the turn in that we have successfully achieved and actually reverse our progress in counteracting the devil UNDERSTEER.

 

Ideas welcome especially before Friday

[Zeddophile]

The proposal of Xa73 to go with 2.5 dgrees of negative camber on the rear has merits ,in that it will increase the amount of tyre contact with the track when cornering, but will this setup  negate the turn in that we have successfully achieved and actually reverse our progress in counteracting the devil UNDERSTEER.

 

For that you need to look at your rear tyre wear patterns, and work it out from there.  The thing to remember with XA73s suggestion is that it is part of a full package setup in a particular way, and the ingredients in your suspension setup are quite different.  I'd almost be tempted to develop the front end more first until you notice less rear grip than front.....

 

As far as brake pads go, I like QFM A1RM.  Run them all round in my GTV6, no issue at Sandown, and they are cheap.  Not quite as cheap as the Lucas pads I believe, but not far off.

[C.A.R.]

No worries Steve - always pleased to confuse!

 

It may cause you to loose some turn-in, but as I haven't tried this myself I can't say for certain.

Give it a go mate & report back!

 

[chev z]

I must admit I am feeling guilty while writing  about liesure activities when so many are enduring so much pain and trauma with the fires.

 

GIVE GENEROUSLY  'Z'  enthusiasts

 

A fair assessment of the front suspension changes weren't accurately available due to the change of rear tyres.I should have left the  225 x 60 x 15  on the rear  , they are definately the best way to go.They allow amuch better transfer of power to the tar and keep the rear end in a tidy line.

Although my fellow competitors said it was great watching the rear end action of my car.It was a full time job to keep it on the black stuff.

 

What was that Neil Simon song  about nearing your destination and

..." slip sliding away"

 

The set up for the Z was  2.5 degrees pos. castor and  3.5 degrees neg. camber.

I ddn't have time to change rear camber ,but will look into it in the future.

 

I suppose there was only one real positve that I could take away from the day, I decided to alter the konis one full turn on the front [ harder ]before my final run , this did enable me to beat my best run on the short  Winton track by approx.    1/3 a sec.

Yes I realise that it is not that significant a drop, but looking on the positive side the car and driver were definately not  "AS ONE "

 

YOURS STEVE

[Zeddophile]

I decided to alter the konis one full turn on the front [ harder ]before my final run , this did enable me to beat my best run on the short  Winton track by approx.    1/3 a sec.

 

1/3 of a second probably covers nearly the top ten places in V8 supercar qualifying, so its not exactly an insignificant gain!  And any gain is of value.

[chev z]

I hope I'm not boring you with my meanderings.

 

It is time to try my first real event.

Winton motor raceway has the  sprint series starting this weekend...round 1

 

I have decided to do the Lurch tutorial front brake upgrade  and only a few other minor alterations to the setup .

The only concern I have is that I can't upgrade the m/c to a 15/16 or 1 inch

Thanks Lurch for tracking one down for me, a pity it won't be hear before raceday.

 

He assures me all I need to do is PUMP the brakes alot before each corner[ lol ].I reckon I might go steady for a trial period ...say one lap

 

Definately replace the "slip sliding" rear rubber, back to the 225 / 60 / 15 ,  the front will also be changed from the 205/50/15  to  205/60/15

 

I won't lighten , change front end castor /camber or the konis  as yet , so as  I can compare the cornering to last time.

I think we have completed the major alterations,  now it is time to fine tune these improvements.

 

Another variable that I really haven't tinkered with is tyre pressures.Perhaps we should keep these as a constant .

 

Any further ideas readily considered.

 

Been to a funeral today  ,  " LIFES SHORT  so everyone  HAVE A GREAT ONE "

[Zeddophile]

He assures me all I need to do is PUMP the brakes alot before each corner[ lol ]

 

You see that quite a bit at sprint days - have an amusing image in my mind of watching a mates brake lights flickering from about halfway down the main straight of Sandown, only to lock the front wheel into turn 1 and end up rallying through the grass while I casually sailed by on the black stuff giving him a toot and a wave  .  The time you have available to sit and observe while driving a standard 4 cylinder on a racetrack...

 

Lurch is of course correct though, you'll probably find the first and maybe also second pump feels spongy, but after that it should be a good firm pedal (until you take your foot off, then you have the old rinse and repeat!)

 

Apart from that, I think you are taking the sensible approach to this meeting - iron out the little kinks, and see how it really runs, then you'll get an idea of where (if at all) to make more big changes.  Good luck, and have fun!

[chev z]

Well we were back onto the  Winton long  track, as I mentioned ,and dropped my PB to 1min. 46.44sec. which is close to 1sec. better.

 

Considering the brake upgrade was placed on hold , I had a small problem with brake line connections not matching, I think the better tyres and perhaps being  a cooler day helped achieve this time.

 

It was a pleasure to get reaquainted with the Devenish family and also see how a Z can be driven, 1min 38's,Pretty impressive steering Rob. I love the passion that the whole family has for the Dattos and the time they have for newbies like myself.

 

One thing I learnt on the day ,was by setting the front konis softer by 1/2 a turn leads to slower times , 1.5sec. to 3sec. a lap.And a couple of dirt driving experiences.

My fastest time of the day was after firming the front 1/2 a turn [ from the original setting] Next time out I will soften the rear by half a turn[ the rear is set on fully firm]

 

Then will begin the lessons on adjusting the bottom settings for the konis, Hell I don't even know what that's called let alone what it does to the suspension .

 

I have another dilema to ponder over the crop sowing period, and that is whether to transplant the V8 Lexus into the 260z or be more patient and buildup the 240z with v8 etc.......mmmmmmmmm?