Sc fuel inj cleaning & flow matching

[911 tweaks]

anyone used Witch Hunter to clean & match similar flowing injectors for an SC engine?
What was the end result from your experience of what done? Tell the + & - of your experience.
Thanks,
Bob

[911 tweaks]

morning bump

[jonbot]

I asked them about this a couple months back and they said that they can't clean the SC injectors, but they can test them for flow.

[911 tweaks]

jonbot, you are correct. only flow and no cleaning. $9/ea to flow test and he is not very excited to do this job, so I understand.

He claims that the injectors are too prone to rust build up on either side of the internal screen and you can't get those flakes out, usually. Best to replace the "SC" injectors and start fresh.

What did you do with your injectors jonbot??

For those reading this, the later 3.2 injectors is a totally different story and they can do all to these i.e. cleaning, flowing,...

[MatthewBrum]

You can try to clean them yourself if you are having trouble

[911 tweaks]

thx matthew for your input.
Basically, I am approaching this build/resto as trying to eliminate any and all possible pitfalls to a successful & nice running engine.
I have back flushed and most "seem" to spray ok, however, I am no genious as to what is ok and what it should be.
Maybe I can get them flowed to match that way. That way I can hopefully get 1 or 2 sets that have all of the injectors flowing the same.

[craigyirush]

Has anyone used this company to clean 3.2 injectors?
Just curious what the improvement might be.
I have no idea what state mine are in but am currently getting
terrible mpg . . .

[Jubbie]

I had my C3 injectors cleaned by Witch Hunter back when he was still saying that he would clean them. They did well. Gave me a before and after test report.

I guess he doesn't want to sign up to doing that anymore. Too bad.

[spuggy]

Tweaks, there's a company that sells a special tool to hold the pintle(?) of the CIS injector open so you can back-flush the injectors. Interested as to how you back-flushed yours? Did you make your own tool?

Guy on the 930 forum said he had NAPA ultrasonically clean his injectors, and the spray pattern went to a wide mist pattern from what it was before.

Apparently you can adjust the flow, they should be within 5% of one another, IIRC.

[911 tweaks]

spuggy,
yes I did do a back flush fro the technique I got from a great fellow and porsche enthusiast of which his name escapes me know, and basically what you do is get a pc of (1 strand) 18 awg wire, use a tweezer tip or such to lift the pintel top up off the injector seat and la-sew the pintel tip, pull the wire strands down the side of the injector, push a 12" long pc of 5/8" id rubber hose down over the pintel end and the wire so as to keep the pintel tip up, fill the hose with berrymans or any other cars cleaner~solvent, put a compressed air hose fitting on the end snuggly and blow 100psi thru the hose, put a rag over the normal fuel input end of the injector and see all of the sh^t that comes out... usually. After this, put the hose on the other end and check the spray pattern out pintel end and check for drips out pintel end when filled cleaner and no air applied.
That is the compressed version. Read it slowly as these are all of the steps and have at it.
This being said, I still bought new injectors for piece of mind and to ensure as evenly as possible the same amount of fuel going into each cylinder as I don't want to burn out a valve or leave any power on the table. These injectors WILL, not maybe, rust, especially with the ethanol in gas now the these injectors are made out of stamped steel. The internal spring on the pintal is steel. Their is a rubber seal on the base where the pintel seats against and these dry out - become hard - basically impede a good seal with the pintel allowing lower pressure to trigger them releasing fuel sooner and longer than spec - hurting performance & wasting gas.
Good luck!
Bob

[jonbot]

Hey tweaks, I ended up purchasing all six injectors. I'll be honest, I didn't really see any difference afterwords. If I were to do it over again, I'd probably send them off and have them all flow tested, and just replace the ones that were faulty.