I have a mono leaf spring that measures 2 1/4 wide at the center and 2 3/4 at each end. The only markings on the spring are the number 3 on one end and the letter G on the top. It was given to me by an old time drag racer and tells me it was a service pack spring for drag racing. I am running my Copo on the f70/14 Goodyear polyglas tires . Has anybody heard of such a thing? The 5 leaf spring in my car is of unknown origin and I am having to run a 1 inch lowering block to get a decent stance. The car will not 60 foot, 2.20. I run the car in pure stock and cannot run cal tracks or other bars. Any ideas out there?