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Merely an observation Geoff, there's no need for you to be patronising :(

I'll say it again - it is obvious to me from reading that Harry understands what he is talking about. I wasn't implying you and SK didn't know what you're talking about so perhaps you should relax your tone.

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You have avoided the questions I posted. And simply restated what you had previously posted. I will try and not fall into that trap myself.

You agree that having a soft arm on one side and hard arm on the other side does not result in stagger of the anti roll rates. That is the case because the kinetic energy is passed from one wheel to the other via the free twisting of the torsional part of the bar.

Is the problem that you are looking at leverage in isolation? One arm is shorter than the other, so the leverage is different side to side. But there is both movement ratio and leverage ratio to be considered. Sure there is more leverage on the side with the shorter arm, but there is an equal decrease in movement for the same kinetic energy. Maybe have a think about that.

A common trap I have seen when discussion this with others is that they consider the arm and the closest bush (to that arm) to be the relevant relationship. When in fact that is not the case, the only relationship that matters is between the two wheels linked by the stabiliser bar. Actually the two springs linked by the stabiliser bar. Which you can see quite plainly see on later Commondoors and BM's where the stabiliser bar links are effectively attached to the lower spring seats.

At this point I think I have typed enough and I have explained it as many different ways as I can. If it doesn't click, then at least I have tried.

I can only suggest that you actually try it, stick the adjustable bar on full soft on one side and full hard on the other side and try a common degree (left and right) slalom. There should be a dramatic difference in anti roll stagger if what you believe is in fact correct. I have done this test with a famous race driver instructor (no I won’t risk being accused on name dropping again). He reckoned I was full of shit, so I asked him to prove me wrong. We set up a Honda Integra with a 24mm Whiteline adjustable rear stabiliser bar, without him knowing, I varied the rear settings between 1 and 3, 2 and 2 and 3 and 1. He couldn’t tell the difference, despite several laps of Oran Park trying. He guessed wrong 3 out of 3 times. Another bottle of Jack for the collection.

Maybe you should have a go at the same test. Since you would mostly race on the Paperclip, which has a dominance of right hand corners, being able to easily run anti roll stagger may be an advantage, if you are in fact correct of course.

:( cheers ;)

Are you reaing my posts? I answered all your questions. but this may make it more obvious for you...

1. You now agree that it is OK to have a rotating adjuster on only one side of the stabiliser bar. That it doesn't lead to stagger in the bar rates. Because I got the feeling that you didn't believe that was the case previously.

I never disagreed. but lets make it clear we are not talking about the rotating blade adjusters that you keep trying to turn the discussion towards. They are fundamentally different in how they work compared to the multi-hole conventional bars in two ways;

a) they do not vary the length of the lever arms, and

b ) they become part of the spring.

2. This means the effect of stiffening one arm (connected to one wheel) is passed to the other arm (connected to the other wheel). This results in a uniform (side to side) increase in anti roll. Is that correct?

no. fundamental problem with what you are saying. The only type of adjuster that you can stiffen one arm on is the blade type adjuster, which is not what we are discussing. The multi-hole conventional bar simply alters the leverage of the torsional effect of the sway bar to the end of the lever arm.

2. Do you agree that shortening the arms decreases the leverage (of the wheel movement) on the bar ? Hence increases the anti roll?

of course you condescending prick... do you? or do you think it is actually stiffening the arm as you said in your previous question?

3. Now if you agree with #1, #2 and #3, please tell me why you think that decreasing the leverage on one arm (connected to one wheel) is not passed to the other arm (connected to the other wheel)?

well, #1, #2, and #2... in the case of the type of bar we are discussing, I disagree because of the reasons i have stated in the earlier questions. and I know you don't like it when i repeat myself,

4. In conclusion, if the stiffness increase (due to less leverage) is passed from one wheel to the other, then why would the anti roll rates be different side to side?

in conclusion, the stiffness of the bar is in the diametre of the bar. the bar applies the same force to both arms, as I have said previously. changing the length of the lever arms simply changes the torque multiplication of the bar to the wheel.

Edited by hrd-hr30

I just did a bit of a search on Whiteline adjustable bars - I didn't know they made blade adjustable bars for production cars! that was a bit of a surprise, and a bit of a dissapointment that they don't do them for my car :D

but anyway, I found something relevant too. They have actually tested the multi-hole adjustable bars in exactly the way we are talking about. No allusions to any "famous race car driver" or trying to confuse the issue with blade adjusters though, just measured data from a test bench :lol:

http://www.whiteline.com.au/articles/NASIO...ymetric_adj.pdf

Edited by hrd-hr30
so you are saying the adjustment holes in the Whiteline bars are all wank then? ie it does not make a noticeable difference to the rate of the bar? That is the only way that it wouldn't produce a noticeably different effect on one side to the other...
Errrr, no, you just said that, I said it would have to be an extremely sensitive chassis for the side to side differences to be obvious.
the website is ancient. Just contact the QLD IPRA Assoc. What car are you planning to run?

Costs? well the same as anywhere else really... as much or as little as you want to spend? You could have had my 1200 for $5000 minus engine and box if you were quick enough. I just sold it to a guy in SA.

Thanks for the info. Planning on SII RX7, preferably the SelectMaz one Issy has that is apparently unbeaten over any series it ran but he wants me to build one with his input. He says he will campaign again next year in Vic.

I was actually referring to the class entry costs, but thanks for the other info too.

Matt, sorry to have come on harsh, but mate I wouldn't comment on what you know about IT security against someone else. It was an unnecessary comment clearly intended to just "bump". Add input that is beneficial to the discussion or not at all.

just saying the adjustment holes either provide a noticeable difference or they dont. if they don't as you are saying, then they're a wank. if they do, they will have a noticeably different effect from one side to the other when setup assymetrically. Unless you're correcting for a serious crossweeight issue, but if I can't even get basic swaybar operation across to you guys, let's not go there...

I just did a bit of a search on Whiteline adjustable bars - I didn't know they made blade adjustable bars for production cars! that was a bit of a surprise, and a bit of a dissapointment that they don't do them for my car  :)

but anyway, I found something relevant too. They have actually tested the multi-hole adjustable bars in exactly the way we are talking about. No allusions to any "famous race car driver" or trying to confuse the issue with blade adjusters though, just measured data from a test bench  :lol:

http://www.whiteline.com.au/articles/NASIO...ymetric_adj.pdf

Yes, they do make adjustable stabilser bars for road cars, I designed a large number of them. For heavens sake did you actually read the test results, let me quote Jim...

Stock rear bars have asymmetric response from side to side.

That test was of Subaru bars carried out in 2002, I actually supervised the test and proof read the results for Jim. It kinda tickles my funny bone that you are quoting it back to me.

At this point it is fairly obvious that you have dug yourself in too deep to back out now and admit that it is even remotely possible that you might be wrong. So I will stop trying to convince you.

:D cheers :)

and the fact that a stock MY02 (or whatever it was) WRX rear swaybar is assymetric in effect has what exactly to do with wether setting up multi-hole adjustable bars different from one side to the other has symetric or asymetric effects? :)

look sydneykid, we're not talking about stock swaybars, we're not talking about blade swaybars, I don't care how many times you say V8 Supercar that or famous race car driver this, I designed that, or whatever you come up with next.

- Asymmetric settings result in asymmetric response from side to side.

just like I've been saying. biatch

and the fact that a stock MY02 (or whatever it was) WRX rear swaybar is assymetric in effect has what exactly to do with wether setting up multi-hole adjustable bars different from one side to the other has symetric or asymetric effects?  :P

look sydneykid, we're not talking about stock swaybars, we're not talking about blade swaybars, I don't care how many times you say V8 Supercar that or famous race car driver this, I designed that, or whatever you come up with next.

just like I've been saying. biatch

One last try, let me table the average results for the Subaru 22mm adjustable rear stabiliser bar at 60 mm travel

Soft/Soft = 2,350

Soft/Medium = 3,017

Medium/Medium = 3,133

Medium/Hard = 3,667

Hard/Hard = 3,933

That is 3 holes on each arm with 5 rates as per my post;

For the guys with 3 holes per arm = 5 settings as follows;

1 / 1 softest

1 / 2

2 / 2 middle

2 / 3

3 / 3 hardest

One last Jim quote, from 2002;

How significant in real world terms is this lack of symmetry? Who knows?

We realise this is just the beginning

We moved on from this with the real world test as I described in the post above, the answer I arrived at was "insignificant" because no one could pick it in a real world (blind) test.

You choose to believe what you want, all I can say is try it for yourself. If you can pick the assymetry (in a blind test) then you will be the first.

:( cheers :)

at least you finally admit the response is assymetric...

funny, I didn't find any followup real world testing on their site... hmmm...

I can pick the difference of loosening my swaybar link pins 3mm (2 turns of a 1.5 thread). Small changes make huge differences to on-limit handling.

And either those adjustment holes make a noticeable difference or they don't. They are altering the leverage arm on each side, either that make alters the rate seen at the wheel or it doesn't. You can't have it both ways just to suit whatever your argument is at the time.

I don't own or work for a workshop and I don't know everything.

coulda fooled me

The standard Subaru stabiliser bar is asymmetric, it doesn't seem to worry the Subaru engineers. They believe it is inconsequential, and their asymmetricity is more than the 1/2 adjustment setting on the Whiteline adjustable rear bar. So I don't have any problem ignoring it and consequently I feel fully justified in sticking by my original post.

Next time you are racing in NSW or Vic, pop into our garage and say g'day. I will be glad to do a blind test on your car. If you can pick the difference, even 51% of the time, you can win a bottle of Jack too. But make sure you bring one with you, just in case you don't.

:) cheers :P

Edited by Sydneykid
The standard Subaru stabiliser bar is asymmetric, it doesn't seem to worry the Subaru engineers.  They believe it is inconsequential, and their asymmetricity is more than the 1/2 adjustment setting on the Whiteline adjustable rear bar.  So I don't have any problem ignoring it and consequently I feel fully justified in sticking by my original post.

Next time you are racing in NSW or Vic, pop into our garage and say g'day.  I will be glad to do a blind test on your car.  If you can pick the difference, even 51% of the time, you can win a bottle of Jack too.  But make sure you bring one with you, just in case you don't.

:P cheers :D

I might be doing Ringwood Hillclimb on the 20th, but that's in someone else's car.

Otherwise, I'm doing a supersprint and hillclimb at Bathurst on Dec 3 and 4. Feel free to bring some bars for the blind test. :(

I might be doing Ringwood Hillclimb on the 20th, but that's in someone else's car.

Otherwise, I'm doing a supersprint and hillclimb at Bathurst on Dec 3 and 4. Feel free to bring some bars for the blind test.  :(

You don't have adjustable stabiliser bars on the car already?

:P cheers :D

Edited by Sydneykid

Sounds like a fair deal. Blind tests are always fun.

I have my theory why a side imbalance is not noticeable. The swaybar links 2 spring/damper combinations, so when cornering as one side is compressed it is also compressing the other. The swaybar in the example above is a 22mm and at that deflection is exerting a greater load in kg than the spring on the opposite side is (as it will on all deflections). This will attempt to force the opposite spring to compress but that compression is limited by the cars body mass. Therefore body roll is controlled equally on each side.

It can be difficult to visualise but the system has to be considered as a whole, and not just a single component working in isolation. To that end I am attempting to get my FEA program working again to demonstrate visually the dynamic relationships.

As a specific response to a previous question; the adjustment holes are not just a wank, but a realistic means of adjusting roll resistance and front/rear traction balance, but offsetting the adjustment holes causing an imbalance is only of consequence in isolation on a test bench. As a system it works. I may prove myself wrong, but that's the cost of learning. :D

BTW Harry, is (was) yours the 1200 with the big engine or the 1200cc donk?

BTW Harry, is (was) yours the 1200 with the big engine or the 1200cc donk?

I always ran an L18 engine in my 1200.

Sydneykid, my 1200's rear bar was adjustable, but that's sold now. The Skyline doesn't have them.

The Skyline doesn't have them.

Do you have the standard stabiliser bars? Or fixed (not adjustable) aftermarket bars?

It's an R31 GTS Coupe isn't it? I designed a front adjustable bar for them a few years back (a friend of mine had a black one). I can organise one for you at a "good price" if you want. They are usually 27 mm (R31's need a lot of antiroll) but if you are running big front spring rates, maybe a 24mm will be OK.

From memory, the rear doesn't really lend itself to an adjustable bar because of the mountings. Due to the rear suspension design, R31's need a serious antiroll upgrade as well. The Whiteline off the shelf, fixed rate bar is 20 mm, but I used a 22mm on the black car. I even tried a 24 mm rear bar to see if we could reduce the rear spring rate, but there wasn't enough anti squat. So the camber change on power down was excessive with the softer spring rates.

PM me if you want to discuss further.

:mellow: cheers :(

the car in my avatar is a HR30. Had it for a couple of years now, and its the one I had when i joined up here - hence the name... It actually handles very well. But I've got no plans to run it at any events. I'm actually selling that one as well. Too many cars!

I bought an R32 GTR a bit over a month ago to replace the 1200 for hillclimbs and sprints. Its still just the way I bought it, with Jap coilover kit (yes, very stiff valving), and adjustable castor rods. Looks like standard bars on it. I'm trying to track down some adjustable upper arms for the front - it desperately needs some camber. If I can't find any (seems to only be the rears that are popular), I'll have to get some made. But otherwise, I'm very happy with the handling and balance of the car.

hrd-hr30, just sit down with a pen and paper till you work it out - SK is right. I had this same conversation 6 months ago and I was one of the people who said "Ahhh... I see now..."

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