IMSA Gremlin

343sharpstick wrote: OK guys, the fun is starting. First thing on the "To-Do" list a new Cage. Some may be OK with what's in there, but If I flip this thing I simply don't trust what's there. My home track is Road America, it's no place to be messing around with safety. I also have the Kirkey intermediate road-race seat so I'll be mounting that too. Question is, What tube Dia. do you guys recommend? I have the SCCA General Competition Rules & Specifications document. Section 9.4 spells it out the regulations pretty clearly, however I do not know the weight of the finished product, so what tube dia. Do I need to use. Here is the chart: GCR Vehicle Weight Tubing Size (inches)/(outer diameter x wall thickness) Up to 1700 lbs 1.375 x .080 1701 - 2699 lbs 1.500 x .095 1.625 x .080 2700 lbs and up 1.50 x .120 1.750 x .095 2.00 x .080 Do I just go with 2.00 x .080 tube dia and be good no matter what or is that foolish. Do I go for 1.625 x .080?  Is there a chance a gremlin could weight more than 2,700 pounds? Probably not but I have no basis to make an educated guess, a stock Gremlin weighs 2,633 pounds per Wikipedia.

Looks like a fun project!

IIRC, 2-inch 0.080 is as good as 1-1/2 at 0.120-inch wall.

As mentioned before I almost bought this car from George Beasley in 1996.  He sent me a great deal of information on how the car was set up, why certain mods were made and how they were made.  I finally found the write up he sent me. 

The write up was done by Ed Allen who owned the car before George.  There is another person, Don who is referenced as having additional information.  Amos Johnson is referenced several times in the write up. 

I also have a Washington post write up on the car racing at summit point.

I am posting it all below as JPG's  If the cars current owner wants a copy of the scans emailed to him let me know.

John

This is really great info for the IMSA RS cars.  I believe the Don referenced is Don Knowles who used to own this car.  He may even still be racing.