ORIGINAL: ukmike
Pe Reivers.
Sorry if you think my approach is "Stupid". but it does offer a very low cost alternative which is what the writer asked for originally.
Also, as I stated in my reply, I have used it many times to quiet existing installations which has made an unflyably noisey plane, flyable.
If the results are not liked then just remove the restrictor, refit the self tappers and fly away, Noisely.
Mike
PE, I guess both of us thought your comment was rude. You said his approach was stupid. Go back and read it. Maybe you didn't mean to be rude but that's how it reads.