First year for dimpled torsion tube?

[frankc]

Hello,
Does anyone know when the dimples in the torsion tube (for extracting trailing arm bolts) was first introduced? I have read this occurred around '73, but I noticed the torsion tube on the '73T I recently picked up does not have them. It is an early build coupe #270, so perhaps it was a mid-model change?

[Chuck Moreland]

Some 73s have the dimples, some don't.

The problem of trailing arm bolt extraction is sometime exaggerated. It is peculiar to the 72 and these early pre-dimpled 73s.

The early pre-915 transaxles cars have enough room to extract the bolts towards the trans.

[frankc]

Thanks Chuck. That's the information I was looking for.

[RD911T]

This thread raises a question for me. I have a 71 coupe I'm rebuilding. Working on suspension reassembly now. I'm putting in a 3.0L and a 915 tranny. Which way should I insert the trailing arm bolts? From the inside and just figure I'll have to drop the tranny if I ever want to remove the trailing arms again? I've redone all the bushings and bearings, etc on the entire rear suspension, so it should be good for quite a while.

[frankc]

Originally Posted by RD911T

Which way should I insert the trailing arm bolts? From the inside and just figure I'll have to drop the tranny if I ever want to remove the trailing arms again?

Using the OEM 14mm bolt, I believe the only option you have is to insert them from the inside as they cannot be inserted from the outside without the dimples.

Another option is to use the Wevo solution:
Welcome to Windrush Evolutions - WEVO - Porsche Products

[RD911T]

Originally Posted by frankc

Using the OEM 14mm bolt, I believe the only option you have is to insert them from the inside as they cannot be inserted from the outside without the dimples.

Another option is to use the Wevo solution:
Welcome to Windrush Evolutions - WEVO - Porsche Products

Thanks Frank, those are pricey. I'll take my chances that my suspension will hold up for a while with the total rebuild.

[wayner]

I've read where people have dimpled the tube themselves

The ones the factory did certainly don't look like they used much more than a ball peen hammer and one swift blow ;-)