Doug1
11-22-2012, 07:29 AM
I have a 2nd Gen project that has an Art Morrison rear clip and front subframe installed. I have included a pic below. The round tube subframe connectors are going to be removed and trashed. What I want to do is use 2x4 tubing, such as the front and rear clips are made and connect the two in order to make a full chassis car that the body can be removed from. I've looked at AME's MaxG chassis to get an idea of how to connect the two and am in contact with AME to get the materials and engineering suggestions on the best way to accomplish this.
After the frame is a full chassis, I'll separate the body from the rocker welds and lift it off the frame.
Now here is the real question I am after. How much torsional rigidity will I lose by converting the body to a bolt on setup. I plan to weld a cage into the sides of the body in order to keep it as hidden as possible. The cage will be similar in shape to the Ridetech Tiger Cage. It will land on top of the frame rails at the front, behind the driver and in the trunk. I'd like to have it bolt down on top of the frame, along with 8 other body mount locations. Those are the factory front subframe connectors, 2 areas at the front and rear of the strengthened rocker area and 1 at the rear bumper support.
I would think that the welded cage and body combo bolting directly on top of the frame would cause very little loss in rigidity but I haven't seen a removable 2nd gen body before so I'm not sure what kind of problems I will be introducing. This is a street car that will be used for autocross.
Is this just a horrible idea or will it still be pretty stiff?
Here is a cut from the build thread which shows the current state of affairs.
I'll get rid of the round tube stuff that was added in which I highlighted in the large blue oval and tie the front and back chassis together with the same tubing used by AME. The tie in within the small blue oval will be left though I prefer to use something other than round tubing since it just doesn't fit well visually with rest of the frame.
https://static1.pt-content.com/images/noimg.gif
Then we'll cut the frame loose from the body in the only other point it is welded in, which is where the cross member hits the rockers. See area highlighted in red.
https://static1.pt-content.com/images/noimg.gif
I'll put plates on the ends of the frame crossmembers and matching plates in the rockers and have it bolt in there.
After the frame is a full chassis, I'll separate the body from the rocker welds and lift it off the frame.
Now here is the real question I am after. How much torsional rigidity will I lose by converting the body to a bolt on setup. I plan to weld a cage into the sides of the body in order to keep it as hidden as possible. The cage will be similar in shape to the Ridetech Tiger Cage. It will land on top of the frame rails at the front, behind the driver and in the trunk. I'd like to have it bolt down on top of the frame, along with 8 other body mount locations. Those are the factory front subframe connectors, 2 areas at the front and rear of the strengthened rocker area and 1 at the rear bumper support.
I would think that the welded cage and body combo bolting directly on top of the frame would cause very little loss in rigidity but I haven't seen a removable 2nd gen body before so I'm not sure what kind of problems I will be introducing. This is a street car that will be used for autocross.
Is this just a horrible idea or will it still be pretty stiff?
Here is a cut from the build thread which shows the current state of affairs.
I'll get rid of the round tube stuff that was added in which I highlighted in the large blue oval and tie the front and back chassis together with the same tubing used by AME. The tie in within the small blue oval will be left though I prefer to use something other than round tubing since it just doesn't fit well visually with rest of the frame.
https://static1.pt-content.com/images/noimg.gif
Then we'll cut the frame loose from the body in the only other point it is welded in, which is where the cross member hits the rockers. See area highlighted in red.
https://static1.pt-content.com/images/noimg.gif
I'll put plates on the ends of the frame crossmembers and matching plates in the rockers and have it bolt in there.