I'm home again, and the book I mentioned is called "JEEP ENGINES - Speed Secrets and Racing Modifications for Jeep-Built 4, 6, and V8 Engines." It was Mopar Part # P4529529, with a 1990 copyright date. It includes chapters on Jeep History, 2.5 engine, 2.46 engine, 4.0 engine, 4.2 engine, 5.9 engine, "Racing your Jeep," and an Addition Info. chapter listing additional resources.
The Racing chapter includes some details on the racing Comanches, including specs. The Craftsman Comanche chassis were standard except for fiberglass fenders and hoods. In addition, the frames were plated and filled with urethane (!!!!) to prevent them from breaking up under stress The 4 cylinder engines were bored out to 3 liters, putting out 230 horsepower at 6500, using a Holley 4-barrel carburetor. They used a Chrysler 904 Torqueflite transmission, the stock item, but of course all rebuilt and modified. The race weight of one of these things was 3900 pounds.
There are also details on the Archer Bros. oval track Comanches, which were 2WD, and used the standard 2.5 engine with TBI, with hand-selected and matched production parts. They used the stock 5-speed transmission, and (for weight reasons) a Dana 35 rear axle rather than a 44. They used an aluminum driveshaft, not only for weight but safety (won't punch through the floor when it breaks). Lotsa brake and chassis mods, extensive roll cages, etc. of course, but basically not too far from stock. They weighed in at 2920 lbs.
Well anyway, there's far too much else to detail here, but the book is fun to browse in.
