rear track width

John Kelly · Post by **John Kelly** » Tue Jun 04, 2002 6:52 am

I think you are probably right, but I'm looking at the rotor surface measurements for better accuracy.

John www.ghiaspecialties.com

Dave_Darling · Post by **Dave_Darling** » Tue Jun 04, 2002 9:17 am

The track is actually from the center of the tire's contact patch to the center of the other tire's contact patch.

In fact, a 914 was DQ'd from winning the national SCCA runoffs back in 73 or so because of the track. They had swapped to narrower "rain" tires, on wheels that kept the outermost side of the tire the same distance from the car's centerline. But the narrower tires moved the inner side of the tire outward, which moved the center of the contact patch outward. This increased the track beyond what was legal in class, so they were DQ'd and some Datsun (I think) won instead.

--DD

------------------
1974 VW-Porsche 914 2.0 (Type IV powered!)

Pelican Parts' 914 Tech Geek http://www.pelicanparts.com

John Kelly · Post by **John Kelly** » Sun Jun 09, 2002 6:40 am

Thanks to everyone who replied. As it turns out, I'll be picking up a cheap 914 this week so I will have all the measurements at hand. I will post some pictures once I get the suspension built.

John www.ghiaspecialties.com

ray greenwood · Post by **ray greenwood** » Mon Jun 10, 2002 5:30 pm

94teener....I think we just said the same thing...in differnt words. When I spoke of axles...I meant the stubs themselves. They are fixed. If they moved, they would become out of plane with the caliper mounts, I must have mis-read the ealier posts, as the drive shafts will most certainly not affect the track. Just curious, are the rear trailing arm mounts on the 914 slotted to allow adjustment for the drive shaft length? I know they are on the 411/412. Its strange, There is a factory set up length in the books for setting the trailing arm spacing. Since there were sevreal joints used over the years, I always suspected it was for if you changed to older or newer joints. They have specific measurements listed to make sure that the CV joints are not over or under extended. I can attest to the fact that under extending them will sooner or later grind off the "C" ring on the end of the shaft. Ugly learning experience back in high school. The rear subframe is slotted, and....yes...as usual, there is a special VW alignmemnt tool to make sure they are centered. Just wondered if the 914 has anything like that. It allows a total track change by moving the trailing arms, of almost two inches in width. Ray

94teener · Post by **94teener** » Tue Jun 11, 2002 5:48 am

Ray,
The 914 trailing arm mounts are not slotted. To a mimimal extent, track, can be affected when rotating the arms laterally during tow adjustments. Camber is adjusted by adding or removing shims to the outboard mounts of each arm. All of the track slack required during movements of the suspension under driving conditions comes from the twin CV joints on each drive shaft.
Phil

ray greenwood · Post by **ray greenwood** » Tue Jun 11, 2002 1:18 pm

94teener...yep they are identical to the 411/412, except for shaft length. What the factory was getting at with their adjustment slots...is that you can run the cv's compressed or extended, but that they should run in the middle of the ball travel in the grooves of the joint to prevent bottoming out on max extension and banging the shaft edge on the metal cup...or putting too much load on the ball cage. I can't think of which method would be more of a PITA...shims...or the centering bar rigamoraole..I have to go through whenver I have a trailing arm off. Ray