i dont know what brand the gauge is, but it looks 100% accurate. it goes to 0 when you relieve pressure, and goes to 38 with the vacuum connected to fpr and 41 when you unplug it.

im not sure a stock fpr is a good idea, the fuel system has been remapped, i have hondata s200 with lots of tuning. maybe i can pull out the injectors and see if they are shooting fuel, but it seems more safe to see if the spark plugs are getting spark. ive never had to deal with these issues before, and the manual for eg sucks for this stuff =/