Bought this thinking it was the same as fuel rail, but fuel rail is a 1/4" and needs to be tapped..   Autometer 2269 1/8" NPT female to 1/8" BSPT male..   Fits perfectly in oil prime plug on passenger side of engine block. I currently have one there with a autometer oil pressure gauge...   Works perfect. You need this adapter if you want to put a guage there...   $10 shipped. PAYPAL only.   http://www.streettunedmotorsports.com/parts/b/autometer_npt_bspt_gauge_adapter_2269.jpg

I've used it for injector cleaning in and out of cars. Never noticed a huge improvement. Probably because I was cleaning old SQ injectors. So I never really got a fair test from it.     When I took the new boat out for the first time it bogged when you throttled it and took 5-10 seconds to get on plane. Reverse was useless because when you gave it gas it bogged and stalled. I figured I needed to take the carbs apart and clean them. But I decided to try the easy route first. I added a can

http://i2.cdn.turner.com/cnn/2015/images/09/17/trumpfaces.gif

Happy Birthday to ya!