Hope the attachment works...
I've written up some specifications. I used MS Word, but posted them here in rich text format and as a PDF. This should allow most people to view them. The posting window says there's less than 22k available for posting so I did not attach the Word version. If anyone wants it, shoot an email to me at
[email protected] and I'll send it.
The format of the rules will probably look familiar, I used NAMBA's rules as a starting point. I did this partly because they already described a stock class. The other thing I liked about the NAMBA rules is they frequently write the rules for an entire type of boat, such as Sport Hydros, and then have a small section listing the engine and hull specs for each class. This makes it easier to add additional sizes later.
Since tunnel hulls are already pretty well defined, I just focused on engines. I don't know what to use for the carb bore, exhaust outlet, or hull minimum, so I just put ??? there for now. I also just realized that I mis-named the class. It should be Stock 45 tunnel rather than stock 40. Edit: another name idea, perhaps it's time for us Americans to go metric and call it Stock 7.5 tunnel.
Since I think IMPBA needs some stock classes, that's the way I wrote them up. I realize there is not a concensus on which way this should go. Something to consider is if we start out with a stock class and later change our minds, nothing is lost. People will be able to do the internal mods when the rules change. However, if we start out with an anything internal goes class, it will be nearly impossible to go back to stock later on. The fact that it will obsolete the engines that have been modified will be used as an argument against it. Since there have been people asking for stock, and finite cost, racing, perhaps this is a good time to give it a try.
I thought about adding a $ limit for the engines to help keep costs down. I know of other types of R/C competition, combat for example, that did that and these classes have become some of the most popular. Right now there's only one manufacturer. If we put a price limit in place, it would provide a guideline for anyone else considering building them. Alternatively, market forces may keep the prices down. A really high performance, and high $, stock engine may not have a big enough market to make the minimum quantity worth producing. A lower $, but good performing engine would have a bigger market. Not including a $ limit certainly keeps the rules simpler, and eliminates the need for periodic price adjustments.
And finally, inspections. I hear the message loud and clear that some want them and some don't. So, what I did is wrote up straw man text for the different kinds of inspections. Then I prefaced this section by stating that the host club chooses what kind of inspection(s) they want to do. Hopefully, this will be a compromise that can work for everyone. If a club feels strongly about enforcement, they can use tear downs to ensure compliance. If a club doesn't want to go to that trouble, they can choose a simpler option such as the Go, No-go gauges.
I also included an engine claim, that was similar to what Don said ODMBA has adopted. This is also up to the host club to use or not use. If the class is going to be stock I feel that there should be some rules with teeth to discourage cheating. The threat of losing one's (modified) engine should be a pretty good deterrant. However, whether the engine claim gets used or not is entirely up to the host club. In thinking a bit more on this, if a club is going to permit engine claims, maybe that should be documented in the race flier. This lets the person with the modified engine stay home rather than travel to the race and discover at the driver's meeting that they are exposed to losing their engine. The host club will have to think about whether they do or do not want to use the engine claim. It might cause some people who have stock engines to stay home. However, Don's club has shown that there is a desire, at least in some clubs, for this type of rule. Other forms of R/C competition have engine claims in place, so it's obvious that they can be made to work.