Surge Tank

(Difference between revisions)

Revision as of 03:08, 30 December 2015

The purpose of an anti-surge tank (swirl pot) is for use with an older non-baffled fuel tank to provide a 100% flow of fuel to the high-pressure pump. The pot itself doesn't require this, the fuel flow to the pot can be occasionally interrupted with no problems. As long as the EFI fuel pump inlet always has fuel the engine will never act up.

Overview

If using a stock Datsun 1200 fuel tank with your EFI system, you'll need to keep the tank 1/3 full.

OR, install an anti-surge tank. Use a low pressure fuel pump (lift pump) to fill the tanklet. Excess goes through a return line back to the main fuel tank. Then use a high-pressure EFI pump, drawing from the bottom of the tanklet, to feed the engine. The EFI return line can be fed back to the tanklet or to the main tank.

Stock Tanklet

Afracer, one of the first club members to swap an SR20 into a 1200, used the stock coupe overflow Fuel Tank as a surge tank

Economical Anti-Surge Tank

From http://www.geocities.com/hrayhouston/antisurgetank.html

I've had fuel injection on my car for many years, even before the rebuild featured on this website. And I've always just had an inline fuel pump and the stock tank with the only change being a return line added. But I've always hated having to keep the fuel tank more than 1/3 full to keep the fuel pickup from being uncovered around corners or on acceleration or stopping. I had several options:

EFI Fuel Tank/System Options:

• Custom fuel tank with internal baffling and possibly an internal fuel pump. $$$$
• Stock tank modified with fuel sump or baffling. $$$
• Custom anti-surge tank between tank and high pressere inline pump. Must have a second pump before the anti-surge tank.$$
• Make my own anti-surge tank, and include an internal fuel pump.$

My economical Anti-Surge Tank:

• Made from an inline water filter housing (GE SmartWater filter housing) purchased for $15 at Home Depot. (There are many brands of these, check the web.)
• Allows use of an internal fuel pump, which are much cheaper than equivalent inline pumps.

(Note - you don't have to use an internal fuel pump, just use a rubber hose long enough to reach the bottom of the tank. If you don't use an internal pump, you can use a shorter 5" housing instead of the 10" housing.)

Fuel Pumps (The one drawback, two are required.): The one drawback to an anti-surge tank is the need for an extra fuel pump to get fuel to it from the fuel tank. I used the inline pump that I had been using to feed the engine to now feed the anti-surge tank. A high pressure pump isn't needed for this, but I already had this one. It feeds fuel to the anti-surge tank and the excess returns to the fuel tank via the return line. I installed a new Mustang internal fuel pump inside the anti-surge tank to feed the engine.