My Home Alignment Setup

[Elombard]

Originally Posted by TT Oversteer

You might be able to get a ballpark setting by measuring outward from the hub centers but the objective here was to get as precise an alignment as possible using a home made setup. Most 911's have different track widths front and rear especially cars with wide rear tires compared to the front. A quarter inch difference will completely negate any accuracy you might be able to achieve with a toe measurement. Now if the center points are known, then you can add or subtract the difference in track width from front to back and adjust your measurements outward from the hub centers accordingly.

Another point to ponder is that you need to establish a thrust line so your car will go straight. Without the centerline reference to square the left string with the right, you could have a situation where the LF is parallel to the LR and the RF is parallel to the RR but L and R are not parallel to eachother.

I will concede that the set up of this project was time consuming but now I have the tools and knowledge to reset my alignment any time I want to experiment with different toe in/out or camber settings or when changing ride height, after corner balance, etc. Also, I have had a hard time finding a Porsche alignment specialist who really knows how these suspensions work andd how to set them up correctly. Sure, I can drive a long way and pay a lot of money to a known shop but then if I change the slightest thing I'm back off to the shop with checkbook in hand.............

I should have added that the front and rear distance between the strings has to be the same. I think yo are suggesting that.

Let me throw out that a "pretty level floor" combined with a slightly tweaked chassis and even though you are measuring from the cars center you could be off more than even a 1/4" in manufacturing tolerance from the hubs.

Check my math here:

if your string is 20ft long or 240 inches.

and you are off by .25 inches

I think you are off by only .001 or .1%

I measure to the car hub not the wheel so trusting Porsche and their OEM suppliers where possible :-)

I got all of this out of Rays Scruggs book and some experience that I have, might save people time but be slightly less precise than what you are doing.

[spence88mph]

Very impressive, just one note, I was told never to use cinder blocks as they can crumble without warning, they're designed to be full of concrete when used structurally. I just did a google search on it and read a lot of people saying the same thing. Not worth getting crushed over, stay safe.

[rick-l]

Originally Posted by spence88mph

Very impressive, just one note, I was told never to use cinder blocks as they can crumble without warning

Looking at the pictures again those aren't cinder blocks.... They are patio blocks on edge.

[Steve W]

Originally Posted by Peter Kelly

Seems to me I can only get about -2 in front and -3 and change at the rear. working from memory here.... probably a mistake

You can get another degree in the front if you shave a half inch off the inside of your camber plates and remove the shock covers, or just use the offset camber mounts from Tarett or Wevo. Or better is to have Rebel Racing raise your spindles and decamber your strut 2 degrees. Alternatively you could use offset ball joints such as from Elephant Racing, but depending, there could be tradeoffs with them.

On the rear, you could remove the camber and toe eccentrics, and use a jack and try to push the trailing up further relative to the spring plate to get more camber. I think Elephant has the Cambermax kit to help you do that, or you could also just weld a nut on the bottom of your spring plate and use a bolt through it to push the trailing arm into adjustment.

[kwikt 911]

"On the rear, you could remove the camber and toe eccentrics, and use a jack and try to push the trailing up further relative to the spring plate to get more camber. I think Elephant has the Cambermax kit to help you do that, or you could also just weld a nut on the bottom of your spring plate and use a bolt through it to push the trailing arm into adjustment."



Lol.... funny Steve but I also use the floor jack with the crowbar method and then insert the camber bolts. On my 72 arms there is just a little too much camber bolt play.

Kevin

[DW SD]

Originally Posted by Steve W

You can get another degree in the front if you shave a half inch off the inside of your camber plates and remove the shock covers, or just use the offset camber mounts from Tarett or Wevo. Or better is to have Rebel Racing raise your spindles and decamber your strut 2 degrees. Alternatively you could use offset ball joints such as from Elephant Racing, but depending, there could be tradeoffs with them.

You can also lengthen your front a-arms for more negative camber.

Doug

[Green 912]

Gallon size zip lock bag with some lube sprayed in and the air pushed out works great as slip plates. No grease getting on you or the tires and no clean up just toss them out when done.

[HarryD]

Originally Posted by Elombard

One other idea if you dont have $400 worth of granite laying around :-)

two pieces of scrap sheet metal with a little axle grease makes a pretty slick surface so the wheels will move and settle etc.

You do not need $400 of granite. You can buy 12x12 granite tiles from Home Depot or Lowes for about $5/sq.