In reply to java and hhaase:
Thanks. I really like the new nose. Looks racier to me and has the added bonus of being less likely to touch the ground in steep driveways (because it doesn't stick out as far in the front).
In my last post I got you guys up to the engine cranking. The next task was to get the car sitting on its tires.
The rear setup is similar to P2 with the struts mounting to plates at the top instead of the multi rod setup of P1. We did change how the toe is locked though. On P2 we attached Cobalt tie rods to brackets on the rear tubes of the frame. This was hard to do because you had to set the height of the brackets in order to avoid bump steer. This also slightly relocated the inboard end of the tie rod, causing toe changes at the extremes of the suspension travel.
We decided that the best thing to do was to fabricate a fake rack (toe link mount) for the tie rods to attach to. The toe link mount bolts in just like the original rack so there is no need to tinker with the height of the inner tie rod end. Also, toe is consistent through the whole range of travel because the inner tie rod end is located where it should be compared to the pivot points of the suspension.
Here's what the toe link mount looks like (don't pay attention to how dirty the car is... it got rained on when we were towing it back from the recent show):
It is actually easier to manufacture than the clamps we used on P2. A long tube is capped with washers with nuts welded inside. Sheet metal brackets (laser cut and folded) attach the long tube to smaller tubes that the original rack bolts go through.
This whole assembly just bolts to the subframe. The height and location of the tube is set when we weld it so there is no adjustment needed. The Cobalt tie rod attaches to the toe link mount and to the knuckle.
We like this new design way more than the P2 design.
The front suspension is the same as P2. The donor Cobalt's rear bearing hubs attach to CNC machined uprights. The control arms are formed in our press and the ends are CNC machined before being welded. The rod ends are chrome-moly. Outer rods are 5/8 hole with 3/4-16 threads and the inner rods are 1/2 hole with 1/2-20 threads.
We found some neat safety washers online that also include a tapered shoulder so that you don't have to use a separate spacer between the washer and the rod end.
We slipped on the brake rotors without installing calipers so that we could get the car rolling as quick as possible. Here it is on the ground:
At this point, there are lots of little things to bolt on and then the body panels. We had to make a new nosecone so I'll go over that process in my next post.
