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IRS twin spring plates
turboboy - December 3rd, 2013 at 07:05 PM

Hi
I have a buggy with IRS and twin spring plates each side.
As far as I know that was how the 1st ones came out.
Is the any adventage or disadventage with them?
Also are the sharfts the same length as single spring plates?
Cheers


Snap Crackle Bang - December 3rd, 2013 at 07:47 PM

In theory the twin plates should be stronger / stiffer. The single plates make it easier to assemble the suspension. Both can use the same torsion bars. Type 3s continued with the double plates. My guess is they changed to single plates on beetles to save a few $$$.


bajachris88 - December 3rd, 2013 at 08:16 PM

Disadvantage of twin plate is you end up with the 'long' torsion bars, and thus can't go to 33'' tyres. 31's are the limit, as 33's rub on the torsion tube cover on the spring plate.

Single spring plates use the shorter torsion bars, and the shorter bars finish closer in, without protruding infront of the tyre tread (hence allows 33 inch tyres)

Strength wise, i never recall hearing anyone breaking a single or dual spring plate. You'd most likely break a torsion bar before that happens (heard that senario a few times!).

I believe the single spring plate, spring plate cover and shorter torsion bars (found in swingers) are a straight swap.

Needless to say, 31's are a great size without going silly, unless you need the extra ground clearance to balance front and have high torque transaxle or engine to suit.


Craig Torrens - December 3rd, 2013 at 08:51 PM

Quote:
Originally posted by bajachris88
Disadvantage of twin plate is you end up with the 'long' torsion bars, and thus can't go to 33'' tyres. 31's are the limit, as 33's rub on the torsion tube cover on the spring plate.

Single spring plates use the shorter torsion bars, and the shorter bars finish closer in, without protruding infront of the tyre tread (hence allows 33 inch tyres)

Strength wise, i never recall hearing anyone breaking a single or dual spring plate. You'd most likely break a torsion bar before that happens (heard that senario a few times!).

I believe the single spring plate, spring plate cover and shorter torsion bars (found in swingers) are a straight swap.




Ok, there's potentially some confusing info above.

Factory single and dual spring plates for the IRS (CV double jointed) rear end share the same length torsion bars. As for strength, well Ive never heard of anyone breaking either. The single plate does allow the IRS arm to move around more (camber change) due to flex, whereas the dual setup tends to hold it better.

If you want to run the shorter torsion bar setup (for tyre clearance) then you will need to modify the spring plate from a swing axle beetle to suit the IRS arm. It is not a straight swap, but its a relatively easy mod to do.:tu: