Im going custom as far as the gauges go. A new speedometer in the stock speedometer location, a tachometer in the location of the stock combination gauge and then 4 2-1/8" gauges where the radio speaker grille was. This is of coarse on my 52.
On thing I noticed with the poly tank is the fact that when you have gas in the tank, on hot days, the tank swells a little bit. At the moment Im trying to think of a way to relieve the pressure in the tank, but not provide an exit for the fuel incase of a turn over.
Newer vehicles have a vac hose that runs from the tank back to the engine and connects to a vac source like on the intake manifold. In line on this vent line is a evap solenoid that is normally closed so as to not create a vacuum leak. When the engine gets to a higher rpm, the evap solenoid is energized and opens allowing the built up fumes to be burnt. Obviously this is done by computer and would be kind of hard to adapt to a non computer controlled vehicle.
The summit tank, and most other poly tanks as I would imagine, have a connection on top of the tank for a return line/vent. I was thinking of making a vent tube by bending some steel fuel/brake line and running it so it does a 180 out of the tank, pointing down at the ground and ending about 2 inches lower than the bottom of the tank. This way, with the tube ending lower than the bottom of the tank, I would think (or hope) that in the case of a roll over, the vent tube would then be high enough that the fuel would not leak out of the tank. Thats just a senario playing out in my head, I have to do an experiment before I go through the work of making the vent line for my tank.
I did read in the owners/installation manual that swelling and sagging of a poly tank is normal. Didn't say anything about tendency to become brittle.
Last edited by drummin52; 09/16/2008 6:18 PM.
