Rear tie bars

[steve_ram]

Hi,
After reading previous post on rear tie bars, I decided to take
mine off and try the car without them.
Once back on the road, carefully at first the car felt no different,
then onto the open road and anticipating any rear wheel steering antics,
gave it some wellie!! still no difference but cruising at high speeds
the rear suspension felt alot softer, which was quickly rectified by adjusting
stiffness of the rear shocks.

I'm leaving this set up on my car, as i feel it is a definate improvement as the rear suspension is now actually working fully, I'm running a mildly tunned
302, whether a more powerfull car would tend to disort the position of the lower wishbones i don't know?

Steve

[callum]

Congratulations. You've just taken the fifth bar off your five bar gate so now it can droop and swoop unhindered. The Jag torque tubes will take much more than you are throwing at them. :+

[simon]

Simon

(was it you I met at Duxford?) very interesting, I have the same car and set up as you, and was thinking of doing the same.

Simon

[robert]

Steve

Great start, I think we should start a movement on this.

Bin or burn the rear tie bars!! Can I borrow someone elses as GDs have never had them. }> :P }> :P

Robert
Forum Admin

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[steve_ram]

>Simon
>
>(was it you I met at Duxford?) very interesting, I have the same car
>and set up as you, and was thinking of doing the same.
>
>Simon

Yes it probably was me, I've got a burgundy car, I remember our chat.
If I can help out in any way, please let me know.

Steve

[dave]

i CAN'T BELIEVE WE ARE GOING DOWN THIS ROAD AGAIN!

These things are called torque tubes because that it what they are.
They are designed not to twist.
If they were designed to be fitted without a radius rod they would have been triangulated.
The way these things work on the Jag is very different to the way they work on our type of car, never the less the Jag axle is designed to have to power transfered from the axle to the car from the radius rod fixing point on the end of the TORQUE TUBE and not the inner pivot points at the sides of the diff.
You only have to look at the way these things are made to see that all the power going through the axle is putting a awful strain on that friction weld that holds the tube to the inner forging.
The Torque tubes are designed to do the same job as a propshaft....Brilliant at resisting twist, but completely crap of you try to use it as a crane jib as the weld has a much higher strength in shear than it does in tear. In the same was as a kitchen roll tube is very good at resisting twist but how long does it last when you bend it over your knee.

Summary.
If your Jag based car has radius rods, they should be solidly mounted, ie. rose joints.

If they are rubber mounted they are useless and the person who designed the chassis should take night school classes in kitchen roll tube design.

If your car does not have radius rods at all the this is because the designer of the chassis realised that the brackets for the rose joints would seriously affect the layout of the chassis or whilst stripping the jag axle they undid the old Jag ones, looked at them , shook their head and then threw them over their shoulder saying "Sod that i cant be a*sed with fitting them things" so they decide to leave them off altogether...They should also attend night school classes for kitchen roll tube design.

Just because the manufacturers of these kits know more about chassis design than we do (allegedly) this does not mean that they know all there is to know, and can you honestly see a manufacturer owning up to producing a crap chassis or saying "Oh we missed that off because we didn't quite know how to fit it".
No they will make up some story about how it is not required because of this, this or this.
For those who don't believe me, just jack up your car , remove the rear wheel and look for the "weak link" in the rear suspension and you will see that it is that inner weld that i mentioned earlier, then imagin a radius rod fitted and then look for the weak link, you should then be looking at the alluminium hub carriers......This is supposed to be the weak link.

The only true way around this without having to compromise the torsional rigidity (Flex)of the chassis is to fit the wishbone and watts linkage set up that Russel posted a picture of last week.

So there!

P.S. The longer the Jag wishbone/ Torque tube, the greater the risk of breakage and flex!

I look forward to the replies to this one.
}>

[russell_ram]

Steve,

Well done, at least someone read, understood and reacted correctly!

Russ

[dave]

Hi Russell.
Im i right in thinking that RAM fitted rubber bushed radius rods?
It's been that long since i was under a RAM i've forgotten what was there.

[simon]

HMMMM.....Interesting..... as the Ram was designed by Adrian Reynard (and as far as I know the only Cobra replica to be designed by a PROFESSIONAL chassis designer) does this mean he does not know his stuff? I guess that would explain the BAR F1 teams current lack of success......If anyone knows an evening class where Mr Reynard could take classes in toilet roll tube design, maybe you could drop him a line.

[StuartH]

are you sure??? I think it was glanced at briefly by Adrian Reynard - I heard a rumour that he had no more to do with it's design than Carol Shelby did (who I believe also rubber stamped it)
Still - it looks good from my completely untrained eye....

Stuart