re index Neatrix question

88911coupe · 02-22-2012, 10:19 AM

I read a ton of threads but can't seem to find this issue addressed, although I'm sure someone has run into it. This is for Neatrix(rubbery, not plastic) springplate bushings on a G50 Carrera. I need to make some adjustments but pulling the plate out and getting it back in the hole in the body shell are a MAJOR PITA. Is there some trick I"m missing?! It seems like I have to pull it all the way out to get the splines separated to rotate toa different spot, up or down. Note, this is for a G50 and theres less room to maneuver since it sticks out further.
Secondly, what is the most important way to measure "height"...is it fender height, spring plate angle, of door sill angle? What is the spring plates are "correct" but the fender height is off, or vice versa?

TIA

will hung · 02-23-2012, 03:36 AM

The factory recommends measuring the distance from the torsion bar to the center of the wheel, parked on a flat surface.

What changes do you need to make on the car? Reindexing torsion bars are for really big height adjustments. Since you have a G50 car, you'll have adjustable spring plates. I think you have +/- 0.5" of adjustment at the spring plate. Is the spring plate adjustment in the middle or maxed out, preventing you from making adjustments on it?

I know with the G50 cars, since the torsion bar caps are so long, you have to pull the side sills off, remove the torsion bar cover, unbolt the spring plate, and then pull it out. Otherwise, you won't have the clearance. To get the spring plate back into the hole with Neatrix bushings, you have to get your self 4 longer bolt than the mounting ones, and whole lot of washers, and work the bushing in by tightening each bolt a little at a time. Slowly, the spring plate will be "seated" enough that the mounting bolts can be engaged. At that point, swap out your "guide" bolts for the mounting bolts and tighten it to torque spec.

If you don't have it already, this is a useful tool for knowing what angle to set your spring plates.

911 Spring Plate Angle Calculator

88911coupe · 02-23-2012, 07:43 AM

Thanks for the reply, it appears I might be able to get the adjustment done without re indexing. I just wanted to make sure there was not some trick for G50 cars that avoids the PITA of having to pull the spring plate out and then using the longer bolts to get it back in. It would be better if you could clear the spline teeth BEFORE the rubber bushing was completely out of the mounting hole in the car tub but that's just not the case.
It seems like actually using the "facotory" method would be problematic in practical terms. I can't really picture how I'd actually measure those points. I was using Wil's calculator and shooting for 31 degrees, which I got very close to but the ride height is off between the rear fenders. I guess I'm wondering what is more critical...to have the spring plate angles exactly the same or have the fender heights exactly the same? Which one is the true "reference"?
Thanks again for the reply

will hung · 02-23-2012, 09:32 AM

The only issue with measuring at the fender is that having a floor that isn't 100% flat can cause slight fluctuations in ride height when measuring at different corners. I always thought my garage floor was pretty flat, at least I assumed that if I park my car in the center that the drain effect would be canceled out left-to-right, but it isn't. I can measure slight variances depending on where I park.

88911coupe · 02-23-2012, 09:52 AM

That's a good point, and I have to distinguish between "flat" and "level"...a floor can be flat as a sheet of glass but not level. In this case I think the fender method would work...correct? On the other hand, a floor that is basically level but has high/low spots would throw off measurements if, for example, a tire was resting on a spot that was a half inch off from the other 3 three corners. I have 4 spots that I have leveled with tiles so I'll make sure and use them to verify. I guess I'm still not clear on what the definitive reference point is for ride height, although I think I'll just stick with the fender method.

will hung · 02-23-2012, 01:47 PM

That's correct. If you can guarantee that the 4 surfaces are level, then the fender method should be good.