The Blue Flame, indeed, had four wheels. At the beginning of our design process I clarified with FIA that we could mount the front tires close together. So we did, about 1 inch apart. We also had asked if the two front tires could mount on a common wheel. NO! So the front wheel/tire assemblies were independently bearing mounted on the front axle. Running on rubber tires was never a problem. We had twelve sets of Cragar wheels and Goodyear tires initially. Goodyear spun the assemblies up to 850 mile per hour!
Goodyear’s tire design for The Blue Flame was an improvement on their previous LSR tire. The chief engineer’s comments on the changes: “Different type carcass fabric increased as far as possible for strength to weight ratio, a product called 1260's/3 cord. Breaker cord was smaller cord for less centrifugal weight. More bead strength with a double bead on each side with the number of bead wires increased to 25x10 approx. Tread compound changed to latest long wear endurance and least amount of co-efficient of friction.”
We lost one wheel/tire assembly when the supporting mandrel broke at speed (I believe a balance weight flew off) on the test fixture. The tire was destroyed but the wheel only suffered some scuff marks. Of course, it was never used after that. We were limited to 700 miles per hour by Goodyear in 1970 only as a precaution, due to our lack of experience at Bonneville. The plan was to return the following year with full power and attempt a supersonic record. One of the tires was used on every one of the 26 runs, several over 600 miles per hour!Two front wheel/tire assemblies were replaced when one began to lose nitrogen pressure. That was probably an O-ring seal in the wheel flanges. Only one leaked but we replaced the pair since it was a time-consuming operation. One rear wheel/tire assembly was replaced after it locked up under braking – while being towed in the pits. The rubber tread was scraped down to the cords. It could have been run structurally, but there would likely have been some imbalance at speed.
The LSR lads who have been running solid wheels may have saved themselves a lot of trouble by running pneumatic (rubber) tires on the Bonneville salt flats rather than having to run at the various desert venues.