Injectors - What is flow matching & why do it?
#1
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Will be removing the fuel rail and intake and figured maybe I would have injectors cleaned at the same time.
Can someone please tell me what it means to have them "flow matched" and what the benefit of same is?
Also, for you Canadians, since Witchhunter won't ship to Canada, who do you recommend...
Thanks
Can someone please tell me what it means to have them "flow matched" and what the benefit of same is?
Also, for you Canadians, since Witchhunter won't ship to Canada, who do you recommend...
Thanks
#2
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They get put in a machine that measures exactly how much each injector flows through it when its open for a specific amount of time. Flow matched means each one flows nearly the same amount, so you dont have one injector that flows 10% less when it is open for 2 milliseconds than the others flow when theyre open for 2 milliseconds. The cylinder with that injector would be running leaner than the others. I dont think you can modify injectors to adjust their flow, all they can do is test several sets of injectors and match them up so they are similar.
I had a set cleaned and tested by this shop and I was happy. Theyre in Port Kells BC tho (5 minutes from me). You could call local performance diesel shops or tuner shops and see if there is something similar near you.
http://www.nwfuel.ca/
I had a set cleaned and tested by this shop and I was happy. Theyre in Port Kells BC tho (5 minutes from me). You could call local performance diesel shops or tuner shops and see if there is something similar near you.
http://www.nwfuel.ca/
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Flow matching is very important if you want a good even burn across all for cylinders. It's is most important on a modded engine with higher boost when it comes into play into getting a decent tune file.
So if it a fairly stock motor I don't see that being necessary
But in just makes it more efficient an un-match set usually run about 8-12% off of the set of four but a match set usually run within 2-6% of the set.
costas
So if it a fairly stock motor I don't see that being necessary
But in just makes it more efficient an un-match set usually run about 8-12% off of the set of four but a match set usually run within 2-6% of the set.
costas
#5
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Be careful taking the manifold and fuel rail off. I think my last mechanic blew my DME that way. Car was fine before i had front engine work done. By the way are you still going to 944fest?
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Be careful taking the manifold and fuel rail off. I think my last mechanic blew my DME that way. Car was fine before i had front engine work done. By the way are you still going to 944fest?
I always disconnect the battery before doing anything on the car to avoid any electrical issues and when working with fuel (spark and fuel vapour are a bad combo).
50:50 right now for the fest. Depends on work.
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#8
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Will be removing the fuel rail and intake and figured maybe I would have injectors cleaned at the same time.
Can someone please tell me what it means to have them "flow matched" and what the benefit of same is?
Also, for you Canadians, since Witchhunter won't ship to Canada, who do you recommend...
Thanks
Can someone please tell me what it means to have them "flow matched" and what the benefit of same is?
Also, for you Canadians, since Witchhunter won't ship to Canada, who do you recommend...
Thanks
#9
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Thanks reno I don't have to pull the rail again.
By chance I installed them in order as tested and #4 has the highest flow numbers.
This should have been the first service completed when I bought the car almost five years ago. It's never run so well.
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..And a trained Porsche Mechanic did this work.
Last edited by sebastian944; 05-18-2009 at 12:03 PM. Reason: more
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Try Markus Blaszak - a good 944 Porsche shop in Canada that does cleaning and flowing.
As far as the failed DME - best guess would be that the brittle insulation on the fuel injector wires broke and an injector shorted out. You can't really blame the mechanic - impossible to see and any movement at all can cause an old harness to fail.
As far as the failed DME - best guess would be that the brittle insulation on the fuel injector wires broke and an injector shorted out. You can't really blame the mechanic - impossible to see and any movement at all can cause an old harness to fail.
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Try Markus Blaszak - a good 944 Porsche shop in Canada that does cleaning and flowing.
As far as the failed DME - best guess would be that the brittle insulation on the fuel injector wires broke and an injector shorted out. You can't really blame the mechanic - impossible to see and any movement at all can cause an old harness to fail.
As far as the failed DME - best guess would be that the brittle insulation on the fuel injector wires broke and an injector shorted out. You can't really blame the mechanic - impossible to see and any movement at all can cause an old harness to fail.
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Mark
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Yeah i figured that. They don't have an oscilloscope when i asked about it. That is really frustrating when your paying their labour rate and they don't have the proper tools.