Rear torsion tube cutting

Split50 · Post by **Split50** » Mon Jan 28, 2002 4:08 pm

Guys, in order to fit a G50 gearbox into my bug I'm going to have to chop the center out of my rear torsion tube. How far in do the torsion bars go? and how much strenthening would I have to weld in to stop the car from sagging? I'm cutting the frame forks off completely so I can move the gearbox forwards to fit a 911 engine.
I'm not mad just trying to make the car I want.
Tim

[This message has been edited by Split50 (edited 01-28-2002).]

Crash · Post by **Crash** » Mon Jan 28, 2002 11:24 pm

The torsion bars go to the center of the torsion housing. If you cut away any of it you will have to either widen the torsion or move the inner splines out enough to run swingaxle torsions with IRS plates. That would give you about ten inches if that is enough. Otherwise you would have to change over to coil overs.

If you cut the center out of the torsion, you would have to incorporate it into the rest of a cage to give it the strength. It is probably the strongest part of the car and needs to stay rigid to keep the rear end in line.

-Mark

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Blind Chicken Racing
www.blindchickneracing.com

Split50 · Post by **Split50** » Tue Jan 29, 2002 2:02 am

Thanks Mark, thats exactly what i wanted to know. Do the swing axle torsion bars mean the suspension would be stiffer than normal?

Single Cab · Post by **Single Cab** » Tue Jan 29, 2002 12:29 pm

Ross,

How do you connect the spring plates if you remove the torsionn bar? Or are you talking about a complete rear suspension remodel?

Thomas

Ross Morrison · Post by **Ross Morrison** » Tue Jan 29, 2002 3:02 pm

The cars I have done this on are either fitted with urethane bushes(inside and out),or have inserts made from phosphor-bronze. Some people think that just using genuine VW rubbers will suffice.

Split50 · Post by **Split50** » Tue Jan 29, 2002 3:42 pm

Ross, no I don't have the motor yet, what have you got?
Am I right in thinking your the guy who's building the split bug with wishbone suspension?
Is there a way of running a stock-ish floorpan modified like this without a rollcage?

Crash · Post by **Crash** » Tue Jan 29, 2002 4:47 pm

In the long run I think you would be better off with the coil overs even though the cash outlay would be more. As for the cage, you would need something to attach the upper coil-overs to. I suppose if it is a street car you could get ones that fit between the stock mounts but you would still need to replace your rear torsion with something. The easiest would be a 1/4 cage but there are a bunch of other options.

-Mark

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Blind Chicken Racing
www.blindchickneracing.com

Crash · Post by **Crash** » Tue Jan 29, 2002 11:42 pm

The suspension would wind up faster but I am running swing torsion on my baja with long travel and don't have a problem. On the street you wouldn't notice it.

-Mark

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Blind Chicken Racing
www.blindchickneracing.com

Ross Morrison · Post by **Ross Morrison** » Tue Jan 29, 2002 11:49 pm

Personally,I would bin the torsion bars completely.Fit quality coil overs(AVO.Spax,etc), this will give you the adjustability that you are going to need.That 911 motor is a heavy lump and you are gonna have to do some suspension tweaking.Coilovers make this much easier.
Ross.

P.S Do you have a motor yet? I have a 911 engine for sale!!

Split50 · Post by **Split50** » Wed Jan 30, 2002 1:46 am

Mark, would a 1/4 cage only be in the engine/ transmission area or does it stick through into the car?
As Ross said a 911 engine is a fair old lump and needs supporting at the rear, so some sort of subframe tying the suspension to the pan trans & engine looks like a good plan.
If at all possible I'd rather not have a cage as I want the car to be a sleeper.

Crash · Post by **Crash** » Wed Jan 30, 2002 10:55 am

The 1/4 cages I have seen that looked like they worked well went from behind the seat (on a bug) up the the bottom of the window and back to support the engine. The front of the cage was supported with bars running forward and down to the front of the door. The only way to see the cage would be to open the door or look down at the window.
Make sense?

-Mark

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Blind Chicken Racing
www.blindchickenracing.com

Ross Morrison · Post by **Ross Morrison** » Wed Jan 30, 2002 1:17 pm

Split 50,yes I am the guy doing the w/bone '51.You can get quality coilovers for approx £100 each(including spring).
I would, and have,used the stock shock mounts.For your application, I would put some type of cage in that supports the shock mounts as well as the weight of the motor.Are you still planning on binning the frame horns?If you are,I would go for a complete rear end redesign.It might be easier in the long run.

I have a 2.4T(carbs),stainless heat exchangers,oil tank the lot.£2000.

Split50 · Post by **Split50** » Wed Jan 30, 2002 2:29 pm

Mark,
I know exactly what you mean, could it be done with the bars running to the front of the doors going to the back of the doors instead?
Ross,
nice work on that split, I hope mine turns out as good. Thanks but I'll pass on the 2.4, I'm hopeing for a 3.0 or 3.2 but there's no rush as I've got to sell my buggy before I can get the engine & trans.
Yes I am going to cut the frame forks off, I'm thinking of a rear end somthing like a 911 with an engine frame at the rear.
Tim

[This message has been edited by Split50 (edited 01-30-2002).]

Split50 · Post by **Split50** » Wed Jan 30, 2002 2:38 pm

Ross, I just went to have another look at the split your working on and the site has gone. Are the pictures anywhere else on the net?
Tim

Crash · Post by **Crash** » Wed Jan 30, 2002 2:49 pm

Well you could run the cage to the back of the doors but the triangulation would suck. If you are getting rid of the torsion housing that removes the entire rear of the car as far as torsional and lateral support. You could try to triangulate to the back of the door and then down to the tunnel but the farther forward you get the better off you will be, especially with a bigger, heavier, more powerful motor. Your sleeper will not do you much good if it is folded in half.

-Mark

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Blind Chicken Racing
www.blindchickenracing.com