Baja Bug
Rear Suspension Update


  HOME

 

Page 2
Go To Page:  1  2  3  4

Back to Baja Bug Update main page

Torsion Housing Modification and IRS Suspension Assembly

 


Modified torsion housing end casting

Just like the 5/1600 car, we modified the torsion housing end casting to eliminate the lower travel stop (to the lower, rear spring plate cap bolt hole) and the "bump stop"; the SCORE rule set for 5/1600 cars allows both these modifications and while we're not going to race this car, we want as much suspension travel as possible.  Removing the lower travel stop gives us several inches more "down" travel and the bump stop is just unnecessary extra weight.......

 

 


Spring Plate and torsion bar installed

This photo shows the final installation of the spring plate with a heavy duty "Race" spring plate cap and "long" torsion bar.  Except for the new spring plate cap, all these parts are race "spares" that we've inspected, refurbished and painted.

 

 


Passenger side rear trailing arm "final" installed

Here, you can see how the trailing arm pivots around the inner pivot bolt and the torsion bar.  The torsion bar and inner pivot don't share the same "axis of rotation" so there is some camber/caster change with suspension travel inherent in the basic design.  We could fix that but we're trying to keep this as much like a "retro" 5 unlimited car as possible.  This is essentially identical to our 5/1600 car with a little less "tweaking" for maximum suspension travel (we have over 12" of travel as configured now and more is available if we want to work for it).....

 

 


Another view of the trailing arm installation

 

 


Micro Stub and Brake assemblies installed

The Micro Stub assembly allows us more suspension travel than a stock VW IRS would otherwise permit, has disk brakes and is much stronger as well.  We'll be using specially prepped "930" CV joints to ensure that we can use all the travel available without binding the axles and CV joints.  Yes, we know that the axle nut cotter pin is not installed yet.....

 

 


It's a "roller" again!

It was a satisfying end to our day at the shop when we bolted the wheels/tires on and rolled it out of the shop.  With the engine and transaxle removed, there is little weight on the back end of the car and the suspension is sitting on the bottom stops.  Once everything is back in place, the rear suspension will sit a bit lower - about like our 5/1600 car which retains some "rake" at ride height (front a little lower than the rear).  We did a quick and dirty 4-wheel "alignment" and found everything exactly as we wanted - the IRS "pivot jigs" helped us get their locations correct for perfect alignment.

 

 


Holding up one of the rear shocks for motivational purposes......

Now that the basic IRS conversion/installation is complete, we'll fabricate and install an internal "roll cage" structure similar to the 5/1600 car structure.  The roll cage serves several purposes: enhanced occupant safety, increased chassis rigidity, it serves as the upper shock mount and distributes the shock loads throughout the chassis.  We'll cut holes in the wheel wells so that the shocks can pass through and be secured to the cage structure inside the passenger area.  That's probably the next phase of this project.....

 

Page 2
Go To Page:  1  2  3  4

Back to Baja Bug Update main page

 

HOME