I'm not saying their's a 100% chance they will fail in the Mach you bought, but their is always the risk. Their are more than afew Mach's that have had them and they destroyed the engine. Some people have still bought them and had no problems. But when they fail, from what I've read, it just happens all at once. I had actually bought a set for my Mach about 3 years ago, but sent them back because they tried to jack me $30 extra dollars for a late price increase. That was before I knew about the problem they were for Mach engines. If it was me, I'd get them out of there one way or another. Hot Rod magazine did a dyno test on them and they actually lost horsepower with them, so all around their not worth it.