rear shock tower reinforcement

[mrm930]

Question - On installing the angled metal rear shock tower reinforcements - how do you weld the back side of the angled bracket?

-cut an access hole through the fire wall to the "rear seats" then weld thru that?
-cut brackets in half (length wise) then weld the inside of the rear half and the outside of the outer half? Then weld the halves together at the top of the brackets
-Just get small and weld behind the bracket?

See these done alot and just curious how to get to that back side... Getting ready to get this completed on my 930 - removed the torsion bars and converted the suspension to coilovers

thanks,
Mark

[mreid]

I slid the mig tip behind it and welded away. Not a problem.

[Flojo]

is there really a need to both-side-weld them?

the welding will end up to a L-shaped fixture,,, I dontt see the need to do the other side.
I mean, its not a primari body-stiffing part, just an improvement in the upper range.
i.e. the shock tower ist about 95% good from factory, adding the angled metal gives it just 5% more. a well done one-side-weld should do the job(?!).

Originally Posted by scotiagreg

[Evan Fullerton]

Or one can let themselves get carried away.

[Flojo]

didnt know there were spots in the body of a tank that looked like the one from a 911...


;-))

[175K911]

Originally Posted by mreid

I slid the mig tip behind it and welded away. Not a problem.

Likewise. Front side full welded, rear side just welded in a few spots.

[KTL]

Note in the picture Evan posted where the shock "cap" was welded in a few places. It's not uncommon for the coilover to try & punch thru the top of the mount.

Rear crossmember, tower damage pics (from coliovers)

You can see in the above link that the RSR style pieces are an important part of the coilover conversion. But you also really really really need to plate-reinforce the actual crossmember itself where it butts up against the frame rails in the engine bay. This member was not designed to carry the forces that the coilovers put into it. So you have to beef up that joint alot.

Also keep in mind that the frame rails around the shock tower/engine bay are not heavily supported. So coilovers put a pretty big load on them and create some flex. That's why dedicated race cars put the rear "legs" of the cage down onto those frame rails because doing so accomplishes two things. 1) it gives the legs a solid place to land and 2) it provides additional frame rail support by transferring the force from the coilovers into the cage main hoop.

[175K911]

Kevin's correct. Note the reinforcement done to my '86:
Shock tower reinforcements
Longitudinals tied to the crossmember
Cage leg tied back to the plates on the longitudinal

Here's the reinforcing plates:


And Cage leg being added:

[Ayles]

At what point do you have to add the extra support? Is it a suspension issue, motor size, wheel tire combo?

[175K911]

Originally Posted by Ayles

At what point do you have to add the extra support? Is it a suspension issue, motor size, wheel tire combo?

Whe you convert to coilovers

[mrm930]

thanks guys..
Mine are not just a angled plate - they are the U-shaped ones, so that both "halves" need to be welded. I will also address the addition of plates at the corners that 175K911 shows in his pics.

As usual - just ask a question on this forum and you get results. thanks again