[fkemmerer]

Originally Posted by Great Asp

Fred,

Thanks!

The Cheif Tuner for Dynatek told me "the software must contain a very important offset for bringing in extra fuel against throttle position". I really think I will need to review all options when I get ready to change the ECU out. I am guessing that will be at the end of this years driving weather.

But first the gas tank.

The standard SPF unit needs help. The best I can tell it has no baffles, and no sump. I may fab a surge tank with a seperate pump and return to the main tank, or fab a bigger, new tank with a surge area. The standard unit is fine for a carb based system, but EFI needs pressure and a half full tank of gas in my car has the gas in the back of the gas tank when I take off under throttle, and the fuel pump cavitates, then the Dynatek system is "unhappy", which pisses off my motor

E

You are smart to get your fuel system into shape before upgrading the rest of the system. Baffles are a good idea. You do not absolutely need a sump as long as you have decent baffles and you keep you tank at least 3/8 full or more. I don't have a sump on my Cobra as it would show from the back of the car. I do have one on my corvette. The thing to watch is that you don't plumb the return into the tank too close to the pickup line as the agetation caused by the returning fuel will then to send air into the pickup line if they are too close. Its also a good idea to have whomever modifies the tank for a return install a tube that causes the return fuel to come out near the bottom of the tank where it will be covered by fuel. This will also help avoid agetation and air getting into the pickup line. You will probably need to install larger lines to and from the tank to a regulator in the engine bay to ensure that you can hold a constant fuel pressure at all engine loads.

- Fred