Anti Roll bars old and new

Ross Nicol

GT40s Supporter
Just thought I would show you the difference between a stock bar and a far more serious one.Which one is which? can you tell. Pic taken just before I installed the new one. /ubbthreads/images/graemlins/driving.gif
 

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Russ Noble

GT40s Supporter
Lifetime Supporter
Very nice Ross.

Is the new bar solid or tube? Is that blade adjustment? It's a bit hard to tell from the photo. When's your next track day? Shall await driving impressions with baited breath.

Good luck with all the mods. Got your new transaxle yet?

Regards
 

Ross Nicol

GT40s Supporter
Hi Russ

New bar is chrome moly tube 4130 I think.It is a blade and I'm gearing up for cockpit adjustment.
First race meeting is not till 22nd April at Sandown and I've got a lot of work to do.New transaxle is in the air as I write so things are falling in to place.Tim Kay has been helping me with the transaxle and this has sped things up brilliantly.I'm going to stick with my old motor to see if lap times improve with the new box alone.
Regards Ross
 
This design has been around for some time and is a great item for adjusting on the fly, especially when road conditions chane for the worse. Some of the aftermarket sales people offer it. All you need are a few measurements and around $1000. Here is the one by JBL as done on a Cobra.Here is the front end view.
 

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Ross Nicol

GT40s Supporter
Yep yours has a blade on both sides Bill.I believe it's only necessary to have an adjustable blade on one side only, because removing the link from either side of any anti roll bar makes it inoperative.What do others have to say on this?Some serious work gone into that Cobra though.

Ross
 

Malcolm

Supporter
One adjustable blade only will reduce the range of stiffness by 50%. If that reduced range is ok for your car then great. If not then perhaps you need 2 blades?
 
Ross,
Looks very impressive. When I looked at your first pick it I thought you had two adjustable bars but now I see it is only one. Who made it up for you? Are you going to run the rear bar as well? I have a drawing somewhere of a aircraft throttle quadrant that would make perfect in car levers for such a system. Although I am dubious about the time I would be able to aford to make changes on the fly while racing. I usually have my hands full focusing on the race. /ubbthreads/images/graemlins/driving.gif

It would be great for that wow factor though. /ubbthreads/images/graemlins/rice.gif

Which Tire combination are you running front and rear?

You started off with the Audi transmission if I remember correctly. Was it the 01E or the 016? Was the main reason you switched to the ZF ratios or longevity?

What are you doing for transaxle this season?
 

Ross Nicol

GT40s Supporter
Hi guys.The blades are made by Derek Van Zan and Mr Bolts (will Croll) made the rest.There is a lot of race engineering expertise around Melbourne.Yes I have a rear bar to install as well.Derek made up the cockpit controls for me too I'll post a pic for you.I doubt I'll be shifting the levers while racing but hope to be able to balance the car quickly during practice/qualifying.I'm not really interested in the wow factor Dave just have the desire to get the car up the front of the grid where it should be.I'm running Dunlop 17" slicks 225 front 300 rear.No I've had a ZF all along.I have a new one going in this year to fix ratio problems in 1st and 2nd.It's a great box and the synchros are great, it never balks me during gear changes.Hope you don't have to wait too long for your car my chassis is #25.
Ross
 
Guys,
I think your missing the point here. You have to have a blade on both sides. Look at the first pic. When in the flat position, it is "soft". Verticle is "hard". Otherwise you would be setting only one side of the car. The central tube is the fixed or anti sway bar, and the blades are the moving or adjustable portion of the formula. The controls allow you to "dial in" the suspension for the given track conditions. The front would take one setting and the rear might be a different setting. It also lets you change the settings on the fly, if the track conditions or tire grip change during the race. Also if rain pops up you might want to go to a softer setting. Are we talking apples and oranges here?

Bill
 

Malcolm

Supporter
Bill, I would beg to differ on your interpretation of the way a sway bar works. Agreed flat is soft and vertical is hard. But you don't need two blades to set a car up. Teh sway bar transfers load from one side of the car to the other. Because they are connected ie a single mechanism overall you can choose to have just one blade and the other side a continuation of the bar. For adjustable you would only have one blade rotate by the cockpit controls.
 

Chris Kouba

Supporter
Boiling Malc's explanation down, the mechanical properties of the sway bar are the sum of all the pieces, and it effects both sides equally as the roll stiffness. The roll stiffness doesn't change due to which side of the car you're measuring. If the blade doesn't have the range of adjustability then it'll do you good to double up (as pointed out earlier). Either way, the effective roll stiffness is the sum of the arms, links, bushings, and crossbar.

Having 2 blades isn't a bad thing, but it's not necessary.

Chris
 

Malcolm

Supporter
Oh and to add to the discussion, for fun I am making a second anti roll bar so I will have two on the back of my car as a test! Wonder how that will feel?
 

Chris Kouba

Supporter
You know, reading my post now it doesn't really seem like it added a lot of clarity or simplification until the last sentence. Sometimes I try to tell a short story and all I do is go blah blah blah.


I work nights. That's my excuse.


Now back to the regularly scheduled topic.

CK
 
Bill is right.
If you run with one blade locked in the vertical position and the other adjustable blade anywhere between horizontal and vertical when cornering the bar becomes part of the spring rate and as one side now has blade deflection and small bar rotation or twist the other side will have no blade deflection and a large amount of bar rotation or twist. The side with the vertical blade " see,s it" as more masse to shift.I know this is splitting hairs and doubt that most drivers would feel the difference,but in setting up a car for road racing both sides should be equal initially. Clear as mud? Hope not.
Regards Jack.
 
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