We need to take things into perspective. Because Dewey's friend has not broken a sub-frame does not mean they do not break. He runs 6-8 races a year in a class that is not known for the bumping, banging, curb hoping, general bad driving that we see on a regular basis. Your typical self-prepped driver who runs 5 races a year will probably never see a broken sub-frame. I am taking 12 cars to Blackhawk this weekend, most will run double classes. So I will get 20 events worth of track time in just one weekend. That is 4 years worth to the "typical" SM racer. The burden of proof that these things break, has to be put on the shops that see 100's of races a year. And all the shops have seen this happen. And I believe all are in favor of allowing additional reinforcements.
Yes, installing reinforcements of whatever is allowed, will be a revenue stream for guys like me. But so will replacing sub-frames, fenders, allignments, etc. from broken sub-frames. And none of us want to see someone get hurt.
My personal experience is that this will become a bigger problem as time goes on. I feel it is a fatige issue. As we get more miles, we get more fatige and more breakage. I can only remember a single NA car with a crack. But I could be wrong. And remember that the vast majority of cars running nationwide are NB's. Tracks with big curbs and bumps on track out, seem to be the most prone to breaking sub-frames. Road America and Sebring are the most often reported. But we have seen them at Blackhawk, Mid Ohio and at Indy (smooth track with BIG curbs). I have only installed a single new subframe in recent years. As mentioned above, it only lasted a couple races.
My proposal was a 4 piece kit, 2 upper and 2 lower. I proposed specing the design, rather than the supplier. I offered to put my drawings out on the internet for anyone to copy. In the end the SMAC and Mazda decided to go with only the lower mounts and only from Mazda. A good start, but in my opinion they only solved part of the problem.
My 2 cents worth.
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