Weber fuel pressure

[Laldog]

What is the recommended fuel pressure for Weber 32 / 36 DGAV carbs?

I swapped in a previously fuel-injected engine and replaced the missing mechanical fuel pump an electric one.

The car seems to run fine at 3.0, but others are suggesting as high as 4.0.

Opinions and experiences welcome.

Thanks.

 

[x_atlas0]

I'm not sure about the Webers, but the stock Zeniths were looking for ~7psi. You may want to up the pressure though, since those carbs are a bit on the small size for the engine.

 

[61porsche]

Psi

for carbs ( Zenith, Solex, or webers) should be in the range of 2,1/2 to 3, 1/2. Higher pressures can result in the float level/ seat having issues with start/ hot start.

A small but important consideration is a check valve to prevent fuel from siphoning back towards the tank resulting in hard starts. Most pumps have this but not all, so read the literature that came with the pump. The mechanical pump had this feature. The caution here is to not use an air hose on the pump to clean or clear blockage which can damage that small check valve which purpose is to close off incoming fuel temporarily so the main diaphram can increase pressure.

Triple webers can sometimes need more pressure, but less than 5 psi; but ideally a larger volume pump is the true solution.

The only other pump consideration is with using certain types. Less expensive pumps operate by magnetic pump action. This sometimes causes fluctations and reported running issues. The factory used a rotorary type pump on FI for smoother delivery with the added benefit of less noise.