been messing around designing my meth tank. im trying to stick it in the place where my passenger side muffler used to be. im going to cut an access hatch to access the fill cap (not shown in drawing). the pump will be mounted in the back (the little sump thingy will point backwards. capacity is 4 gallons. im going to build it out of 16gauge ss304.

for the filler cap im not sure what to use, maybe a vented gas cap or get a non vented cap and get a roll over shutoff vent. price wise it looks like the tank will cost about $110 for the stainless +fittings. anywho tell me what you think

 

water/meth injection pumps arent designed to be submerged like fuel pumps are, I am saying that as this appears to be a feature of your tank.

A real easy cheap way to make a muffler sized and shaped tank would be a large (6-9in dia) peice of PVC pipe capped on both ends. Pipe that big is really tough with like 3/8in wall thickness. You could probably buy a scrap and the caps for $30.

 

the pump is going to mount to the back and have the feed come from that little sump thingy.

 

im sure the pvc would hold but im not sure if that would pass tech.....anywhere.