If you blew a plug at high idle then I'd suspect it's got nothing to do with the fuel or compression. Usually that would mean there's something rubbing inside the engine contaminating the plug. One thing I'd suggest though is to use an air filter on the carb because it may be sucking in some sand. Bruline filters are about $5. Dropping the nitro is probably a good idea though because the ASP is a fairly high compression and when the pipe comes on it then has a really high compression .