You said that 6 companies started to copy your invention within 3 months and that now is "9 months later." If it's been more than one year since your first public use, it's too late to get a patent. If the first anniversary of your first public use is coming up, you have until then to have a patent application on file. And, don't think that you can file a quickly thrown together provisional in hopes of cleaning it up later. There's no reduced legal standards for provisional applications, so you must have a full, legally-sufficient patent application on file by the first anniversary of your first public use.
Now, let's look at your economics. You've estimated about $20 million in gross revenues in the next 2 years. I'm betting your estimate for preparing and filing your patent application was around $10,000 -- about 0.05% of your projected gross in 2 years. What I don't know is your projected net from sales of your part -- so the economics may not be quite as lopsided as it appears when looking at the gross. Since you asked for simplicity, net = gross - costs (net = profits, gross = total money coming in).
So, let's look at the cost of not getting a patent (assuming a patent is a perfect tool to prevent others from making, selling, using your invention without your permission -- it isn't). How many units would you sell in 2 years if competitors are free to make and sell your invention? 50,000? 10,000? Calculate that gross (your units x $200 -- for easier math than $195) and determine the difference from $20 million -- that's your opportunity cost from not being able to stop competition for your invention. If the difference is more than $100,000, it seems fairly clear that a patent would be a good thing for you.
Now, it's entirely possible that, despite the economics, you don't have the $10,000. First, imagine that Donald Trump said he'd let you in on an investment in which you give him $10k and it's likely to pay $20m in 2 years. Do you think you could get the $10k then? Probably. It's often a matter of motivation -- how much are you willing to give up and stretch yourself to put $10k into something. I'm sure it sounds self-serving, but every time I get soft-hearted with clients I find myself scrambling to find creative ways to pay my mortgage. Patent applications are hard and not exactly over-compensated. So, the costs are real -- not entirely greed-based by patent practitioners.
Second, some practitioners are willing, in rare cases, to accept a "piece of the action" instead of money for fees. The reason such cases are rare is that practitioners still have monthly expenses, like mortgages for example, and can't defer all income to business speculation. My personal opinion is that investing is best left to the professional investors, not amateurs like patent practitioners.
That brings up the last possibility -- find investors. $10k for $20m in 2 years sounds pretty sweet. In racing, you probably talk to sponsors all the time, so you're used to asking wealthy people for money and making your best case for investing. So, it shouldn't be too strange to you to ask for investment for your invention rather than for racing sponsorship -- you're just selling return-on-investment (ROI) rather than advertising.
I hope that helps.
Regards.