Dino Saga 051009 Tires and wheels are continuing subjects on FerrariChat. Lots of questions and the best answers seem to come from the racers. My Dino was raced in its early years and that is where my Gotti wheels came from. I have known no other but have learned a lot about that kind of wheel and a variety of brands and sizes of tires. Gary at Ronal asked about offsets for 16 wheels a month or so ago and I went out and measured mine. Posted the results then and the resulting drawing is the first picture below. Lets dig a little deeper. The original Dino wheels were by Cromodoro, 6 ½ wide and 14 dia. Offset was 4 from inside of tire mounting surface to wheel mounting surface at brake disk. Tires were 205/70 VR 14X all around. Tread width was a nominal 6.5 but I measured an actual 5.75 on my spare. Things were changing rapidly in the mid 70s. Low profile was showing its stuff and racers went where the gold was. 205/55 VR 16 were the widest tires that would fit in the stock front fenders. Tread width was/is 8, 1.5 wider than stock. Cleared outer fender lip by ¼ and just touched inner body panel at full lock. You can go to lower profile but you cant go to wider tread without hitting somewhere. My front wheels are 16 dia., 8 wide and offset is 4. I bought the car with Goodyear Eagles all around, 205/55 VR 16 up front, 225/50 VR 16 in back. The rear has more latitude but there was not too much choice in the late 70s. 225/50 VR 16 was available, 2 wider tread than stock, and could be used with 8.5 wide wheels with the same 4 offset as the front. Gotti had such a wheel. Bingo. The two sizes were the same as Ferraris choice for the 308 so legitimacy was guaranteed. Hardly any change in diameter either so little speedo error. I have tried 250/50 VR 16 in the rear. Too wide or not enough offset. Outside of tire meets fender in bump. If wheel width went to 10 and offset went to 5 all would be OK. There is plenty of clearance on inside of wheel well. Someone else will have to find the limits. The balance did go funny with the larger rear tires. There is not enough power to keep from pushing in corners. I sold the 250/50 tires after 500 miles and went back to the 225s. But not to the Eagles. Have taken many trips to Las Vegas, and have paid my share of fines. Freeway driving with the Eagles was bizarre. They wanted to lock onto expansion joints and then come off with a lurch. I had had good luck with Falken with my Alfas so tried a set. WONDERFUL! It was a new car. Smooth as silk on freeway and good grip on curves and in the rain. Ran them until they became hard to get and tried Yokohama. OK but not a nice as Falken. Now have Kumho and they are OK but a pain to balance and keep balanced. Will not buy again just for that reason. Falken seems to have come back so I may be back in business. Why not Pirrelli, etc. performance tires? I drive around town or on freeways. I need a tire that is safe at 130, lasts 30,000 miles and costs under $100 each. Racers need more. I dont. Its that simple. The Gotti wheels are made of two aluminum spinnings, a cast aluminum hub a spacer/seal disk and a rubber V ring. Simple, light and strong. If heat treated properly and assembled carefully. Many were not. I had leaks early on and tire shops said that Gottis were notorious leakers and fragile. Better buy new wheels! I decided to find out what was wrong and fix it, if possible. Turns out that most problems were simple and cures were easy. Second pic is a section of the tire and wheel, pretty close to scale. Leaks were/are from corrosion under rubber V-Ring air seal. Design does not capture seal. Air pressure is relied on to keep it in place. A layer of silicone can seal it nicely. Turns out that the kind of silicone is important. Clear leaks air. Blue is better but still permeable. High Temp Red is just fine. Pull tire, run bead of red silicone around seal, smooth with Dawn coated finger, re-mount tire immediately, inflate to 50 lbs, let silicone cure for an hour, balance and go drive. Leak cured. Usually. One wheel is still OK after that treatment. 19 years later. One was re-built like so: Remove tire, remove 5mm bolts, take wheel completely apart, clean everything and Scotch-Brite seal surfaces. Throw V ring away. Apply red silicone to both sides of spacer. Apply silicone to inside of wheel halves where seal will be made. Bolt everything together using new bolts and stop nuts. I used stainless and so far so good. Torque everything. Smooth silicone in groove over spacer. Mount tire, pressurize to 50 psi. and let cure. Work fast. You want to stress spinnings while silicone is still fluid and can fill every crack. Third wheel had silicone treatment but has become a slow leaker recently and I will have to re-build it one of these days. Fourth wheel was a special case. Left front had had a hard life. Maybe hit too many rumble strips or hay bales. Maybe just bad heat treat after spinning. There were cracks in the outer spinning around bolt washers and two places just inside the first roll. Could not get another spinning so went to a local machine shop that had a certified TIG welder and a big lathe. Pulled wheel apart, threw away 1/8 spacer and V ring. Turned a disk of #6000 3/16 aluminum plate to a diameter ¼ outside of cracks. Clamped everything square and made a deep penetration weld between disk OD and inside of rim. Bored out center of disk, cleaned everything up and match drilled bolt holes. Sent rim to LA for heat treat to relieve all stresses. Put wheel back together with red silicone and have had no trouble for 19+ years. Extra 1/16 wheel width is not noticeable. 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