MFI fuel filter overflow/diverter valve help

[Chris Pomares]

My understanding is these are supposed to hold about 14 pounds of pressure. About 1 bar. We ordered a new one from Stoddard. The spring only holds 2 to 3 pounds. We can't hold enough pressure to start a new MFI engine build. It looks like this one is for a carb engine. Was there a Porsche carb engine that used one of these?
Does anyone have a NOS Bosch one for MFI they would sell me? I need help, and a good NOS one of these. Our old one had a 9 stamped on it and nothing else. Any insight would help. We have tried 3 fuel pumps and they all deliver the proper 900 to 1000 cc's in 30 seconds to the engine compartment. When we pinch the line headed back on the return line next to this valve we get fuel pressure. Help.
Chris

[edmayo]

Are the last 3 digits on the pump 009 or 001. The 001 is for MFI and will put about 30 psi.

[Chris Pomares]

I'll have to look. The diverter valve at the engine fuel filter console says 9, or maybe 09 under that line on the valve.?
We only get 3 pounds of pressure at the engine. The same as what the spring compression tool says.

[Chris Pomares]

Ed,
False alarm. I think you know Steve Rowe. This was his first time using a 123 Distributer. Timing was off. It runs close to fine now. He is going to spend some time studying how to get the best curve. Sorry for taking up your time. All the best.
I hope to shoot some video tomorrow.

[Richy]

Your post is somewhat confusing , the part is a pressure / check valve and the fuel pressure if measured correctly should be 10 to 13 psi , the engine will not run correctly if the pressure is low . The pressure valve is available new from a Porsche dealer , and there
is not a model for carburetors .

[Chris Pomares]

Yes. Your correct. We only were picking up 3 pounds of pressure not 9 to 11 so we suspected fuel delivery. Steve has built many awesome engines and 3 perfect 901 transmissions for me. He has never set up a 123 Distributor. Once he focused on it he realized he needed to change timing set up. It now runs well.

[gled49]

What did the distributor have to do with low fuel pressure? I assume u were measuring pressure in the MFI fuel hose loop.