Wrong 24LB Injectors? Part 0 280 155 715
#1
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Fuse 24 Assassin
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Fuse 24 Assassin
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Wrong 24LB Injectors? Part 0 280 155 715
I bought a set of S300s for my S4 and some injectors a while back. While they are 24lb, these Design III injectors appear to be missing the groove for the injector clips. Did I buy the wrong ones?
#2
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I remember reading that some people were cutting their own groove in some injectors to fit the clips...but I can't say for sure if they were this model. I know people have used Design III, although they seem to be thinner. I'm not sure if any of them have the groove?
#3
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Get your Dremel out a cut a groove.
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Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
#4
Team Owner
#6
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These injectors look "too narrow" at the top section-presumably that is what Hilton alludes to in his post.
Check measure the diameter of your stock injectors at the ring groove point and measure same on the new ones- I would hazard a guess that there will be a few mm difference.
Rgds
Fred
Check measure the diameter of your stock injectors at the ring groove point and measure same on the new ones- I would hazard a guess that there will be a few mm difference.
Rgds
Fred
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#8
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Full disclosure, I have three sets of these 24 pounders and should sell one or two at some point. Long story. However a twist of safety wire seems to do the trick perfectly. A full harness could be done also. The light blue injector is secured as well as the other (stock 944S2 I think). A possible alternative might be an O ring in place of the wire.
*EDIT* a Dash 012 O ring stretched over the injector top in place of the wire works perfectly. The clip is harder to get on but holds well. The upsides of the O ring is that it won't ***** your fingers and will not fall out of place with the clip removed.
*EDIT* a Dash 012 O ring stretched over the injector top in place of the wire works perfectly. The clip is harder to get on but holds well. The upsides of the O ring is that it won't ***** your fingers and will not fall out of place with the clip removed.
Last edited by Jfrahm; 05-19-2015 at 11:31 AM.
#9
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Gasoline, 55 psi rail pressure, aging hi-voltage ignition wires and red-hot exhaust... Seriously?
Keep in mind however that not all 24# injectors are the same. Flow rates and latency differ, and an ECU maps created for one injector won't be appropriate for another.
Keep in mind however that not all 24# injectors are the same. Flow rates and latency differ, and an ECU maps created for one injector won't be appropriate for another.
#10
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Sorry if my real-world experience does not comport with your internet-based speculation. Or maybe I'm unfamiliar with the hidden titanic forces that might rip a ziptied injector out of the fuel rail? Probably. Not.
I have 19's in my blower car right now and FWIW they seem captive despite not having any clip or alternate retainer. Maybe some manifolds lack a step in the injector well but I recall seeing one in the 87, and that injector will not move down at all let alone pop out of the rail. The injector body might prevent it if not whatever I thought a saw in the manifold. So in my application the clip might just be for assembly. Maybe in other years the clip more critical and since it's easy you might as well run one. The stock clips are not very strong however and so I doubt there is a great deal of force acting on them.
I've heard of injectors shifting down and dislodging but my first thought was that it was a human factor problem.
-Joel.
I have 19's in my blower car right now and FWIW they seem captive despite not having any clip or alternate retainer. Maybe some manifolds lack a step in the injector well but I recall seeing one in the 87, and that injector will not move down at all let alone pop out of the rail. The injector body might prevent it if not whatever I thought a saw in the manifold. So in my application the clip might just be for assembly. Maybe in other years the clip more critical and since it's easy you might as well run one. The stock clips are not very strong however and so I doubt there is a great deal of force acting on them.
I've heard of injectors shifting down and dislodging but my first thought was that it was a human factor problem.
-Joel.
#11
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Joel, start at post #18.
https://rennlist.com/forums/928-foru...-cranking.html
Probably a human factor problem, but your bailing wire trick is also a pretty epic human factor problem too. It may work for now, but what happens when that o-ring dries out ever so slightly and that bailing wire relaxes ever so slightly after a couple hundred temperature cycles and all that vibration, in the next few thousand miles?
I make enough human factor errors that I need all the safety margin I can get. Which includes buying injectors with molded grooves where they belong, and properly attaching them to the rails.
https://rennlist.com/forums/928-foru...-cranking.html
Probably a human factor problem, but your bailing wire trick is also a pretty epic human factor problem too. It may work for now, but what happens when that o-ring dries out ever so slightly and that bailing wire relaxes ever so slightly after a couple hundred temperature cycles and all that vibration, in the next few thousand miles?
I make enough human factor errors that I need all the safety margin I can get. Which includes buying injectors with molded grooves where they belong, and properly attaching them to the rails.
#12
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Modding cars isn't for everyone. However a solution that holds the injector in place adequately is a solution regardless of anyone's ability to mock it.
My blower car did not even have injector clips on it when it came into my possession, and it'd run for years and probably at least 5k-10k miles without them. I'm not sure yet if it's possible to dislodge an appropriately sized injector, at least in an 87 S4, if the rails are mounted properly. Maybe with a hammer and chisel. Maybe in other years the fit is different.
All that being said I think one should use a retainer even if it's pointless once the rail is installed, and when I settle on injectors for the blower car there will be one in place. It's not challenging to do adequately if you are OK with tolerating some ignorant mockery.
-Joel.
My blower car did not even have injector clips on it when it came into my possession, and it'd run for years and probably at least 5k-10k miles without them. I'm not sure yet if it's possible to dislodge an appropriately sized injector, at least in an 87 S4, if the rails are mounted properly. Maybe with a hammer and chisel. Maybe in other years the fit is different.
All that being said I think one should use a retainer even if it's pointless once the rail is installed, and when I settle on injectors for the blower car there will be one in place. It's not challenging to do adequately if you are OK with tolerating some ignorant mockery.
-Joel.
#13
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Seriously I can't dislodge them by hand. But then that's just real-world experience.
-Joel.
#14
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'87 rails are different from '88-95 rails, the early '87 with rubber buffer mounts and later '87 getting aluminum spacers, so maybe there's a detail difference that we're both talking past here. All I know is that with '88-95 fuel rails, if you mount a stock injector plus its o-rings without a retaining clip on it, and bolt the rails down, you can absolutely move the injector up and down with your hands. That's been my experience based on an 'n' of about 6 engines' worth of fiddling with fuel injectors. Hence my paranoia about clipping them properly.
How do your fuel rails mount to the intake?
How do your fuel rails mount to the intake?
#15
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FJfrahm you have a PM.
I would prefer not to ebay these injectors to finance a different set of design IIIs.
I have an early 1987 car build date of 10/86.
I would prefer not to ebay these injectors to finance a different set of design IIIs.
I have an early 1987 car build date of 10/86.