Spring Plate Angle?

arbita1 · arbita1's Garage

I've done some searching but surprisingly cannot find any info on this.

Now that I'm half done with installing my Neatrix bushings on the spring plates, I'm getting ready to re-index the rear torsion bars.

I'm installing 29mm t-bars and I'm looking to go with Euro ride height.

I've used this calculator... http://rennlight.com/cgi-bin/spring.cgi

And guesstimating my weight at 2,800 lbs. (I have a targa without AC) it's telling me the spring plate angle should be between 22 - 23 degrees.

Can anyone give me a feel if this is right or wrong? I don't want to do this twice...like I did on my 944.

Zeke · 09-04-2007, 01:13 PM

That's a reliable site. If that's what it says, go with it.

tdatk · 09-04-2007, 04:11 PM

Matt,
Don't do like I did when I did mine. If your car is up on rear jack stands and the front is on the ground, subtract the angle the car is on from the calculation. You can measure the angle from the door sill.

Jon Merck · 09-04-2007, 04:20 PM

Sounds about right Matt, I just installed 31's in mine at 21deg...just make sure you leave yourself some adjustability with the spring plate bolts. It is a pain to have to undo everything to move one cog.

arbita1 · arbita1's Garage

Quote:

Originally Posted by Jon Merck

Sounds about right Matt, I just installed 31's in mine at 21deg...just make sure you leave yourself some adjustability with the spring plate bolts. It is a pain to have to undo everything to move one cog.

Jon,

What kind of ride height did you get with that? I was looking at your for sale pics and it looks lower than euro ride height in some pictures and in others it looks like it is about euro ride height.

If you set yours at 21deg and you are running 31's, I'm wondering if having torsion bars that are 2mm's smaller and being only 1 or 2 degrees higher on the spring plate is enough...considering how low your car looks. Although it might just be the angle of the photos. I want to try to stay close to euro ride height...although a touch lower is okay.

I'm setting my spring plates to the middle so I have adjustablitly up or down later on.

Edit...

I just realized...I think in the pics where your ride height looks correct, you are running 205/255 and were it looks lower you are running 255/275. So I think the tire profile grew underneath the wheel well and made it look lower. Optical illusion. Am I right?

Jon Merck · 09-04-2007, 08:20 PM

Yes, you are right the 275/40/17's are taller. I should have used 275/30/17's. Spent this evening working on alignment after the Tbar installation. Dialing in more camber and readjusting ride height and toe...I will let you know what I end up with. I am shooting for 24.25" front fender lip, 25" rear, 2.0 deg neg camber front 2.5 rear, 1/8" front toe and 0" rear. Hope this helps.