1972 Beetle rear disc conversion & upgrade rear Suspension

[rrb6699]

first the rear Suspension then the front.

Which of these rear disc brake kits will fit my '72 Beetle?
http://www.mamotorworks.com/VW/subcateg ... e-packages

Suspension:

I want to upgrade the rear Suspension. I'd actually like to beef it up as I want to make this bug a cornering beast.

how do I determine if I have IRS or not on the rear Suspension. I know it affects the disc brake conversion from drums. also, would like to keep use of Emergency Brake.

on a side note, I need to replace upgrade the front suspension too so need to discuss how to do that as well.

I'd like the back raised higher than the front and don't know if I can raise the rear Suspension easily and just keep the front stock height (or same height it is).

thanks in advance,

RR

[neil68]

Is your '72 a Super Beetle (MacPherson struts in front) or a standard Beetle (beam with shocks in front).

Either way, the rear is probably IRS, as '69+ were all IRS in the USA (unless you got a transplanted Canadian standard Beetle that came with swing-axle).

IRS has two CV joints on each rear axle side. Swing-axle has no CV joints anywhere. Google both and you'll find pictures.

It is rare to raise the rear of a Beetle...most people drop the front with dropped spindles and/or disc brakes to get the rake appearance.

Your '72 came with 4 X 130 mm wheel pattern, so presumably you'll want to retain that pattern, with e-brake. So, you'll most likely want an IRS 4 x 130 disc kit with e-brake. I have the EMPI 4-wheel discs on my '68 swing-axle Beetle.

Are you going to add disc brakes to the front?

[rrb6699]

yes going to eventually add discs to front.

rear has a problem on right side where the large axle nut keeps loosening and starts a grinding noise till I re-tighten it. restricts any type of cornering if I have to make sharp turn left it's more likely to loosen again.

would rather upgrade the rear Suspension first.

RR

[Bruce.m]

How tight are you going?
That nut needs to be very tight. More than you can manage unless you have a 4ft spanner (or a 3/4" power bar with long pipe extension).

[rrb6699]

I think 275 ft lbs. but, it keeps getting loose and if it's gonna restrict my driving around corners I need to change it. I may enter in rallies eventually so can't be worrying about a problem like this.

are there different axles or rears I need or do I just have to be stuck with this type of rear setup?

this is a German Bug.

I was looking at the different systems that allow you to raise or lower w/o much effort too.

I have a cheater pipe I use over a breaker bar with the right socket on it.

rr

[Ol'fogasaurus]

yes going to eventually add discs to front.

rear has a problem on right side where the large axle nut keeps loosening and starts a grinding noise till I re-tighten it. restricts any type of cornering if I have to make sharp turn left it's more likely to loosen again.

would rather upgrade the rear Suspension first.

RR

Bruce.m's input is very good but to be honest, if you plan on staying with VWs then I would look into investing in a Torque Dude (or others by a similar name). It has a 9:1 ratio on it so 30#s of torque gives you 270#s of torque on the nut. A lot of guys torque them to over 300#s but I have never tried that. The Torque dude also works on flywheels also.

If you go to the newbie section look for lowering a bug. It is pretty general but my have something for you. They talk about avis adjusters which are easier to install than the Sway-a-way style but not as strong. Besides dropped spindles there are a couple of other ways to go but you also may need to look into adding shims to the lower beam if you go too low. There is also a lowering chart posted that might help some in lowering the rear of your bug.

I did thing on rear torsion bar adjusting and you will find it just below the above listing.

[BAJA-IT]

If the axle nut keeps loosening up, you may have a spacer that is crushing. If so, you will need to replace the spacer to be able to keep the nut tight.

[Ol'fogasaurus]

When my buggy did something similar it turned out that the axle nut had to be torqued tighter and I replaced the spacers... just in case. I also replaced both the inner and outer bearings to be sure that they, or their race were not damaged. I always suspected the long center spacer as the ends looked like they were starting to flair.

Which ever it part it was or all of them were problematic it worked. I don't remember anyone posting dimensions for the spacers so if someone could it would help others a lot.

Lee

I did some additional searching and the spacer kits can be had for under $40. You might find some good prices on dBay too but be careful. The general feeling from reading is the stock spacers are quite soft; you can find better quality spacers from some of the aftermarket resellers.

[rrb6699]

That would be great. I mistakenly thought the noise was coming from the front so I took and repacked the front bearings on both sides, then it stopped, but, when it started up again I took the car to an open lot, pushed it and walked beside each wheel till I found it.

The funny thing is the cotter pin is still intact but it still loosened up. Now what you tell me makes sense about inner & outer spacers, etc.

Good info.

RayRay

[Bruce.m]

Could you be running out of thread due to some issue or another with the spacing? That would explain how you can fully torque it but not have a tight fit (& come loose with only a small movement of the nut)

[Ol'fogasaurus]

Could you be running out of thread due to some issue or another with the spacing? That would explain how you can fully torque it but not have a tight fit (& come loose with only a small movement of the nut)

If this were to end up being true then he might want to check the threads on the end of the stub axle. I have seen stubs with the threaded area bent, stretched or the whole threaded area missing. All usually from mass abuse! Riding on the sand can be hard on things especially whene there are things around to jump.

[rrb6699]

you can fully torque it but not have a tight fit (& come loose with only a small movement of the nut)

.
.
The castle nut couldn't be moving because the cotter pin would have to shear for the castle but to move. That's not occurring. I think it must be loosening up on the other end of the axle somehow.
.
Is there a formula for estimating foot pounds of torque without a torque wrench? So, let's say I have a 4' cheater bar over my breaker bar, how many foot pounds would that impart or maybe what is the ratio per pound of force applied?

RR

[Bruce.m]

Linear relationship. Torque = force * distance from fulcrum.

[SCOTTRODS]

Using a Bathroom Scale... If you have a 3 foot bar (from center of nut), stand on the scale and push down on the bar at that point exactly, until you remove 100 lbs from the scale reading... that's 300 foot pounds of torque. This is how we did it when I was young and couldn't afford tools. Never had trouble with axle nuts coming loose.

[rrb6699]

I've re-tightened the nut, just to update, re-inserted the cotter pin. I am not going to do any hard cornering with it until I can beef up suspension and bushings.

I've put new shocks on for now, but, need to get a complete set of bushings. with 1972 beetles, do all bushing sets fit or do I have to be specific when ordering to get the correct bushings?