Definitively take off the mustache bar T2

[Alpha]

Hello,
For a buggy, I would like to have all the advantages of the engine supported by the trans like in a type 1 (Free motor access, ...) and those of the rear axle of a 74 T2 which currently equips my chassis.
I am looking for feedback to strengthen the fixing of a manual gearbox on which a 1600 will be mounted.
How do you advise me to proceed to permanently take off the mustache bar and just have the engine supported by the T2 transmission mounted on a T2 chassis ?
Thanks

[oprn]

I am not 100% clear on what you are asking due to the language barrier but maybe this will help.

I have a sand rail with a type 2 transaxle and a type 1 engine. It is supported by the transaxle tail stock mount on the front end and the mustache bar mount at the rear of the engine. There has been no problems with mounting it this way and other than it being tight for full flow filter connections, no access issues.

I also have a fiberglass street buggy with a type 1 transaxle and a type 4 engine. I did not use the mustache bar mount on this car, the engine is mounted only to the transaxle like the original type 1 engine. Again no problems with the mounting itself but access is limited by the body shape, the engine cage and the exhaust system. This is due to trying to keep the package neat and compact.

Is your type 2 transaxle the later type with the two ears on top for the stock mounts? Perhaps you could post some pictures?
_________________
Our cars get old, we get old but driving an old VW never gets old!

[Alpha]

[BFB]

sounds to me like OP want to use the rear suspension & trans from a T2 and a 1600 engine in a buggy ... and NOT support the engine with the mustache bar.

bus trans, fine.

not supporting a 1600 with a mustache bar, not sure how you would anyhow unless the bar was mounted to the oil pump plate / studs which seems like a bad idea to me.

T2 suspension for a buggy, horrible idea, might as well just weld your suspension solid. I gad a rail someone did this to , no idea why other than it was all they had available ...
_________________
"how am i supposed to torque the rear wheel nut to 250 ft lbs??? " - clonebug
An interesting thing happens in forums where everyone starts parroting the same thing and "common knowledge" takes over.
Most experts aren't.

[Alpha]

[BFB]

[Alpha]

Thank you BFB for your contribution.
I agree with you that few buggies are equipped with T2 IRS.

The people who made this change keep it. They just note a slight loss of buggy agility. The comfort, however, is maintained and depends on the choice of shock absorbers.

The buggies I know have kept their rear engine mount.

It remains to define the best way to remove the mustache bar and not have any at all.

[BFB]

post pictures of the ones your talking about?
_________________
"how am i supposed to torque the rear wheel nut to 250 ft lbs??? " - clonebug
An interesting thing happens in forums where everyone starts parroting the same thing and "common knowledge" takes over.
Most experts aren't.

[oprn]

Sorry I was slow at getting back to you. Life got in the way, well, death actually. Lost my sister on Thursday.

Yes I was one of the ones that used a type 2 rear suspension in a sand rail. Two reasons, 1) I wanted to get rid of the old swing axle which had been run out of oil and was locked up and go to IRS. 2) I had a parts bus.

There are several advantages, 1) lower gearing for off road. 2) The Bus drum brakes are awesome on a light sand rail! 3) It's a self contained unit as in, it's a plug and play IRS conversion. Just weld it in and go. No messing around trying to get the rear wheels pointing the right direction.

Here is the BIG disadvantage. BFB is dead right about the ride quality! It is absolutely BRUTAL! The rear suspension rarely flexes at all. You can take the shocks off and throw them in the bush and it makes NO difference!

I have a stress fractured vertebra from driving it that my doctor tells me may never heal properly at my age (62 at the time) so I now live with back pain every day!

Remember that the VW Bus was rated by the factory at a 1 ton load capacity and we are using that suspension in a 800 pound Buggy?!! There is NO give! The only way I can use my Buggy is to run 11" wide ATV tires on the rear at 4 psi. The tires are really the only active suspension I have.

...and, I slow way down for the bumps!

Now I think you will go ahead and use it anyway so buy a kidney belt and a back brace and carry on. I see no reason you cannot suspend that type 1 engine from the original Bus transaxle mounts. Being off road though I would build a "U" shaped strap to go under the bell housing and tie it into the Buggy structure for additional support.

My 1600 engine has the universal replacement case so I used the Bus mustache bar and welded it to the engine cage. The only other mount is the stock rubber Bus mount on the front of the transaxle. Yes it is rubber mounted at the front and solid mounted at the rear with nothing in between. Been like that for 8 or so years now with no issues.

Oh! If you have false teeth I would take them out when driving the Buggy or they will rattle and folks will think the engine has a loose connecting rod!

Just kidding!
_________________
Our cars get old, we get old but driving an old VW never gets old!

[Pez]

[Alpha]

[jsturtlebuggy]

One way to soften the suspension would be to grind the torsion bar to a smaller diameter.
I heard of a lathe being use to do this, but can lead to the breaking the bar from surface it leaves.
_________________
Joseph
Fair Oaks/Orangevale, CA
Elrod Motorsports
Motion Tire Motorsports
Having fun with Dune Buggies since 1970
Into Volkswagens since 1960

[oprn]

I would think that any machine shop that is set up to grind crankshafts could do it. I would consider that as an option.

Thanks for the kind thoughts!
_________________
Our cars get old, we get old but driving an old VW never gets old!

[Alpha]

Thank you for your help

Regarding buggies equipped with T2 rear axles, they are generally reinforced and fitted with a T4 or water-cooled Golf engine. They are therefore more powerful and heavier, resulting in a suspension feel that is less compromised than with a lightweight 1600.

So I continued my research on torsion bars, which is as follows:

1) The stiffness increases with a factor of 4 relative to the diameter. So if we double the diameter of a torsion bar, its stiffness increases by a factor of 2x2x2x2 = 16

2) The stiffness is inversely proportional to the length, so if we double the length, the stiffness is divided by two

3) And the same applies to the lever arm; if we double the length of the leaf that connects the torsion bar to the hub, then the stiffness is divided by 2

For point 3), the T2 leaf being slightly longer than a T1 leaf, we get a coefficient of about 0.94

For point 2), the bar of a T1 swing axle being 552 mm compared to a T2 bar which is 610 mm, we get a coefficient of about 0.90

For point 1), the diameter of a T1 torsion bar is generally 22 mm, while that of a T2 is generally 26.9 mm (But there are others). Simply due to its larger diameter, the T2 torsion bar is 2.235 times stiffer than the T1 bar.

Overall, a T2 suspension is generally 2.235 x 0.9 x 0.94 = 1.9 times stiffer than a T1 suspension. This result is consistent with the difference between T1 and T2.

In France, T2 bus between 1968 and 1971 were equipped with bars with a diameter of 26.2 mm, resulting in a firmness increase of 1.7 between T1 and T2. This is the better ratio I found for plug and play.

So, the first solution is to find the softest possible torsion bars. What are yours ?

Thank you for the second solution would be to reduce the diameter of the torsion bars; with a diameter of 23 mm, the firmness is similar to that of a T1. But this carries the risk of weakening the bars.

The third solution is to take the torsion bars from a T1 along with the splines from the chassis and leaf springs, and then machine and weld the splines into the T2 chassis to be able to mount the T1 torsion bars in T2 Chassis.

What do you think?

[oprn]

To my knowelage the IRS type 2 only came with one torsion bar diameter. At least here in Canada.

I have considered the possibility of making a sleeve to fit the type 1 bar into the type 2 housing but the diameter difference is such that the resulting sleeve would be thin and fragile.

I also have not compared the lengths between the two.

I think reducing the diameter is the best solution. I was wondering if the bars would have some sort of case hardening that would be destroyed in that process but have been assured by fellows here that there is no case hardening on them.

Quite frankly I think a set of 21mm Beetle bars would be more appropriate for a light sand rail than the more common 22mm bars.

A type 4 engine by the way is only about 60 pounds more than a type 1. That's the weight of a spare tire moved from front to rear.
_________________
Our cars get old, we get old but driving an old VW never gets old!

[BFB]

I think with the stock travel distance itd be more cost effective to switch from bus torsions to coilover shocks than it would trying to convert to T1 torsions. You get an 8” stroke coilover from speedway motors really reasonable.
Although just turning down the T2 torsions would be a good experiment if a person had their own lathe so it didnt cost them anything but time. I would think that if the bar was turned down then sanded & polished smooth so theres no places for a crack to start to form it should be good to go
_________________
"how am i supposed to torque the rear wheel nut to 250 ft lbs??? " - clonebug
An interesting thing happens in forums where everyone starts parroting the same thing and "common knowledge" takes over.
Most experts aren't.

[dustymojave]

[Alpha]

Thanks BFB for the fourth idea of installing coilover shocks This solution is very interesting because it could be plug and play.

Regarding the machining of the torsion bars, I think it will also be necessary to perform a heat treatment such as tempering, and possibly a stabilization to relieve any stresses that may appear during machining. For example, gradually heating the bars in an oven up to about 300 °C, leaving them for a few hours, and then letting them cool slowly in the oven.

Oprn, regarding the assembly of T1 bars, what do you think about keeping as much material as possible at the splines of the T1 leaves in order to make thick and smooth cylinders on the outside, and drilling at the splines of the T2 leaves to match the diameter of the T1 cylinders? This way, we slide the T1 cylinders into the T2 holes and weld them.

The same goes for the central flutes: we recover as much material as possible from T1, make spacers to fill the space with the T2 tubes, and weld everything in the right place according to the length of the T1 bars.

This would probably be a feasible solution, but it requires some machining and welding work.

[oprn]

[Alpha]

Thank you for your information and this exchange

I continued my research, I haven't found any information yet on machining torsion bars.

I contacted a buggy club in the Netherlands via Facebook. According to their initial information, they use original T2 torsion bars. Here is one of their buggy.

And I summarized the different T1 and T2 bars in a table.