930 fuel injectors

[dr07845]

Can stock 930 fuel injectors be cleaned or is it better to replace?

[reclino]

They are cheap from vendors like *******(R*oxcxkxAxuxtxox*, some people try back flushing and Porsche used to publish a procedure for this. I have built a little pressure tester from a little hydraulic bottle jack, it allows you to check each injector for pattern and leakage. Cleaned and tested all my injectors, put them in long term storage and bought new ones. They are more similar to the Fuel Nozzle on a T64 turboshaft engine than they are to modern fuel injectors. I have installed, calibrated and provided training for these test stands through work. I wished I could flow my Porsche injectors on that test stand..... But even if I could I would prefer new nozzles to used.

[Alan L]

I hve spent some time flushing them - some years ago. I posted some pics etc on it. Held the pitel open with a fine piece of wire and back flushed - gas bottle pressure and a hose clamped over the pintle end and injector cleaner pressure fed thru. Oodles of it. Di it really makie a diffrence? not sure. I am sure if you had a badly blocked one you could relieve it for a while - there is a fine screen on the inlet side.
But really I think new ones are the way to go.
Alan

[RarlyL8]

We have flushed them and re-used just to have them fail again a few months later. The root of the problem is they are worn out. New injectors significantly improve idle and overall smoothness of engine operation.

[Axel84]

What is the best injector replacement up to 400 whp?

[Alan L]

I am just running standard injectors. Your main limitation will be fuel delivery.
Alan

[reclino]

The injectors do not set the fuel flow, CIS fuel head determines the flow to each injector, the injectors is better described as a fuel nozzle, it creates a pattern and atomizes the fuel delivered to it. That being said the euro fuel head (cast iron painted black) had larger lines to each injector, and different PN for the injector, 400 HP on CIS is probably beyond the fueling capabilities of a stock US spec system. The euro spec non lambda system may work better.

[RarlyL8]

The Euro -009 fuel injectors support the most flow by volume. The -017 USA injectors (with skinny lines) will still support 400+whp. The Euro fuel distributor (-037)will support ~375whp in stock form, USA (-145) ~350whp at best.

[flightlead404]

Originally Posted by reclino

400 HP on CIS is probably beyond the fueling capabilities of a stock US spec system. The euro spec non lambda system may work better.

its working fine for me. making 400 at the wheels, no sign of being fuel limited

[Toddrivers]

Cleaned my 009 originals a few years ago. If I had to do it again I would buy new ones.
The cleaning seemed to work out and supports all the HP I ask for.