There is a lot of good information on the forum about lowering the front end of a Speedster with dropped spindles and the like. When you do that how do you lower the rear end of a car eqipped with IRS. Thanks for the info.
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There is a lot of good information on the forum about lowering the front end of a Speedster with dropped spindles and the like. When you do that how do you lower the rear end of a car eqipped with IRS. Thanks for the info.
The rear suspension spring plates can be replaced with aftermarket adjustable spring plates to make rear suspension height adjustment a simple task. Newer IRS Intermeccanicas have rear ride height adjustment as a standard feature via a single bolt and locknut on each side; I'm not sure when that feature was introduced into the Intermeccanica build.
If you have an IRS IM, look up at the inner trailing arms next to the front of the transaxle on each side. If you see a large bolt with locknut (bolt screws in toward the front of the car) that contacts a stop then your car has the adjustment. Basically the bolt acts against the stop to change the at-rest position of the trailing arm.
If you have an IRS IM, look up at the inner trailing arms next to the front of the transaxle on each side. If you see a large bolt with locknut (bolt screws in toward the front of the car) that contacts a stop then your car has the adjustment. Basically the bolt acts against the stop to change the at-rest position of the trailing arm.
The same procedure is used for both IRS or swing axle trannys. I have heard that there is a problem with clearence with the body for the IRS axle cover.
The rear end uses two solid torsion bars. One for each wheel. The spring plate must be jacked up, the cover removed and the plate pried sideways to clear the stop. There is a special tool for this dangerous task or a floor jack can be used. Once the plates tension is removed by lowering the jack to relax the bar, marks should be made for reference. Marks should be made on the shaft, plate, and some reference point on the body.
The plate can then be removed. Removing the plate from the shaft should be next. The inner spline makes a larger change than the outer spline. Depending how far you plan to lower the car should determine whether you will remove the shaft or just change the position of the plate.
There is a large amount of great shop manuals for working on the beetle chassis. I suggest buying a few before trying this potentially hazardous job.
(Message Edited 11/26/2002 10:56:06 AM)
The rear end uses two solid torsion bars. One for each wheel. The spring plate must be jacked up, the cover removed and the plate pried sideways to clear the stop. There is a special tool for this dangerous task or a floor jack can be used. Once the plates tension is removed by lowering the jack to relax the bar, marks should be made for reference. Marks should be made on the shaft, plate, and some reference point on the body.
The plate can then be removed. Removing the plate from the shaft should be next. The inner spline makes a larger change than the outer spline. Depending how far you plan to lower the car should determine whether you will remove the shaft or just change the position of the plate.
There is a large amount of great shop manuals for working on the beetle chassis. I suggest buying a few before trying this potentially hazardous job.
(Message Edited 11/26/2002 10:56:06 AM)
The VS I just purchased also has the adjustable spring plate. A wise investment. I am not sure what kind of range this adjustment has but it can make life a lot easier when trying to dial in the right height and handling characteristics.
There are a few ways to accomplish lowering the rear. And how low you go is probably as much looks, as function. And ground clearance is a consideration. Verathene bushings seem to be a standard replacement.
1)to lower, reset the oem spring plates effectively unloading the torsion bars and alowing the car to settle lower in the back end. Bently manual, or James Hale's book have good desriptions.
Sway-A-Way has a couple of options, (swayaway.com)
2) the adjustable spring plate which replaces the oem. Alows adj of about 1.5", progressively unloads the torsion bars.
3) the rear torsion adjusters (which mount like front beam adj) in the center of the tube.
4) a lowered spring plate by Red 9 Design a UK business. Functions like a dropped spindle in front. (red9design.co.uk)
1) is the cheapest but you will need to use coil over shocks or an air shock to replace the lost suspension.
2) seems most popular due to the availability and adjustability, a stiffer shock seems to accomodate to the reduced torsion suspension.
May need the shorter torsion bars??? if so added cost.
3) costly in labor to install if it's not already there, same effect on suspension as #2.
4) costly to ship, not adjustable, maintains full suspension travel.
My IRS has torsion bars extending about 4 " past the spring plates. In order to replace the spring plates, torsion bar holes had to be opened on the rear fenders and the later covered with covers from Klasse356 (.com) The simulated holes didnot line up with where the bars neede to pass through.
(Message Edited 11/26/2002 6:07:46 PM)
1)to lower, reset the oem spring plates effectively unloading the torsion bars and alowing the car to settle lower in the back end. Bently manual, or James Hale's book have good desriptions.
Sway-A-Way has a couple of options, (swayaway.com)
2) the adjustable spring plate which replaces the oem. Alows adj of about 1.5", progressively unloads the torsion bars.
3) the rear torsion adjusters (which mount like front beam adj) in the center of the tube.
4) a lowered spring plate by Red 9 Design a UK business. Functions like a dropped spindle in front. (red9design.co.uk)
1) is the cheapest but you will need to use coil over shocks or an air shock to replace the lost suspension.
2) seems most popular due to the availability and adjustability, a stiffer shock seems to accomodate to the reduced torsion suspension.
May need the shorter torsion bars??? if so added cost.
3) costly in labor to install if it's not already there, same effect on suspension as #2.
4) costly to ship, not adjustable, maintains full suspension travel.
My IRS has torsion bars extending about 4 " past the spring plates. In order to replace the spring plates, torsion bar holes had to be opened on the rear fenders and the later covered with covers from Klasse356 (.com) The simulated holes didnot line up with where the bars neede to pass through.
(Message Edited 11/26/2002 6:07:46 PM)
One thing when considering adjustable spring plate is that the adjusters stick out about 1/2 and inch or so. In my case there was not enough clearance to fit them with my 7" wheels and 205 tires. Best to check.
One more option..
Take a look at Ricola Racing's website. His Subaru (he has a post here with the link) powered speedster has adjustable coil over springs at the 4 corners. The set up looks infinitely adjustable and clean.
Take a look at Ricola Racing's website. His Subaru (he has a post here with the link) powered speedster has adjustable coil over springs at the 4 corners. The set up looks infinitely adjustable and clean.
Victor: Please see Speedster rear wing @ Gen/non/tech. Thanks