Injectors and Spray Pattern
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I think the pattern changes dramatically from a single long pulse versus very fast short pulses, as under real conditions. So, you can clean them this way, but you can't evaluate the spray pattern unless you cycle them rapidly. Also, holding them open for very long may not be good for the solenoid.
Sorry to confuse with the pictures. I am essentially saying that the four streams LOOK like the 2 streams (but there are four). By saying this I mean its a stream of fuel instead of what I IMAGINED it to be, which was a fog of smaller droplets in a larger fan - like the other pic.
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From: Washington "Dc"
If you're using an adjustable FPR you may be too low on the rail .
Low fuel pressure will stream like a garden hose. 36psi on the rail or 55 should give you the pattern you want.
Dirty injectors are quiet and leak. Run seafoam and carb cleaner through them and check them with 36~40 PSI and re-evaluate.
You may want to rig a momentary switch so you can pulse them . If you hold them open (As someone else mentioned) the solenoid can burn up its a small one made to operate in short burst.
Low fuel pressure will stream like a garden hose. 36psi on the rail or 55 should give you the pattern you want.
Dirty injectors are quiet and leak. Run seafoam and carb cleaner through them and check them with 36~40 PSI and re-evaluate.
You may want to rig a momentary switch so you can pulse them . If you hold them open (As someone else mentioned) the solenoid can burn up its a small one made to operate in short burst.
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If you have complaints about the 4 hole injectors you should see the single hole early euro injectors, just like a hose on a hard spray. Now because of this issue I bought motorcycle injectors some years ago now. This would require 2 injectors per cylinder which for you Brendan would not be an option due to the ethanol issue and compatibility and fuel flow volume.
RC injectors have better injectors than 4 hole injectors. Not sure how many holes but it could be about the same as one of my motorbike injectors which have 12 holes each. This means that I would have had 24 holes spraying and that would be fairly fine in terms of pattern. Direct petrol injection injectors could be an option? It would require a lot of work for a small return. They spray in more of a fog than a diesel. Most EMS systems can't run a direct injection system. Bosch aftermarket can, I don't believe Motec can, or they certainly couldn't. It is very top end expensive technology. I wouldn't go there myself.
RC injectors have better injectors than 4 hole injectors. Not sure how many holes but it could be about the same as one of my motorbike injectors which have 12 holes each. This means that I would have had 24 holes spraying and that would be fairly fine in terms of pattern. Direct petrol injection injectors could be an option? It would require a lot of work for a small return. They spray in more of a fog than a diesel. Most EMS systems can't run a direct injection system. Bosch aftermarket can, I don't believe Motec can, or they certainly couldn't. It is very top end expensive technology. I wouldn't go there myself.
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If you have complaints about the 4 hole injectors you should see the single hole early euro injectors, just like a hose on a hard spray. Now because of this issue I bought motorcycle injectors some years ago now. This would require 2 injectors per cylinder which for you Brendan would not be an option due to the ethanol issue and compatibility and fuel flow volume.
RC injectors have better injectors than 4 hole injectors. Not sure how many holes but it could be about the same as one of my motorbike injectors which have 12 holes each. This means that I would have had 24 holes spraying and that would be fairly fine in terms of pattern. Direct petrol injection injectors could be an option? It would require a lot of work for a small return. They spray in more of a fog than a diesel. Most EMS systems can't run a direct injection system. Bosch aftermarket can, I don't believe Motec can, or they certainly couldn't. It is very top end expensive technology. I wouldn't go there myself.
RC injectors have better injectors than 4 hole injectors. Not sure how many holes but it could be about the same as one of my motorbike injectors which have 12 holes each. This means that I would have had 24 holes spraying and that would be fairly fine in terms of pattern. Direct petrol injection injectors could be an option? It would require a lot of work for a small return. They spray in more of a fog than a diesel. Most EMS systems can't run a direct injection system. Bosch aftermarket can, I don't believe Motec can, or they certainly couldn't. It is very top end expensive technology. I wouldn't go there myself.
24lb injectors on a stock engine with Ken's chips should be okay for my ethanol usage (I use it in all of my cars now - except my wife's acura). I have to turn up the fuel pressure and will need to turn up Ken's resistor for richness I believe. The more complex issue is that ethanol will act differently with reference to the "port wall pooling" phenomenon, and it could cause issues later on with the other cars, boost, and aftermarket ecus -
but I have digressed -
this is just for getting a cheap 85 on the road for DD duty. I have redone the top end and wish to put in the best used injectors I have.
But with your mentioning RC injectors - I am tempted to unbox the 75lb RC units I have in my desk drawer! See how those suckers look!
Maybe I will take some pics. For that I will need to employ the help of my 9 year old son to at least hold the camera.
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From: Texas
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Normally everything I do requires custom fabrication, so no easy just drop them in unfortunately. So other than the idea, I can't help you, sorry.
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OK, it might be worth giving witchhunter a call. Perhaps the 4-holes you have are not correct for our application. The stock single hole S4 injectors throw a decent spray pattern due to the center pin.
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I have some S4 injectors - I can try and test them as well.
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From: Texas
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