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L-Jet injectors

 
Old 02-14-2012, 12:06 PM
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umc276
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Default L-Jet injectors

Been thinking it would be nice to change the 30yr old injectors ('83 928S) for new set of Ford type.

Problem is the expense and bother of new fuel rails and hold downs.

Since there is so much distance between the stock fuel rail and injector (2" hose connector between), seems as though a simple 1" adapter-barbed at one end for a short hose connection with the rail, and a cup at the other to accept the new injector with the O ring would work.
Probably $5-$6 cost each to have machined if a small quantity were ordered.

Before I look into this further, would appreciate any comments from those who know more about this setup than I do.

Also, has anyone converted the L-Jet to Ford type injectors, and if so, any problems?
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Old 02-14-2012, 12:12 PM
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i would be worried about how that cup is held down on the injector.
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Old 02-14-2012, 12:14 PM
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If the car runs well why bother ? the rest of the car is 30 years old as well. No point looking for things to change which do not need it and will not improve how it runs. Plenty of things WILL need replacing as they fail. And the question should be "any benefits ?"
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Old 02-14-2012, 12:56 PM
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http://www.fiveomotorsport.com/impor...uel-injectors/

Or 928motorsports
http://www.928motorsports.com/parts/ljet_injectors.php

They all are pricey..... Typically the high wear item is the little bit of hose from the injector to the rail....I just bought a bunch of fuel hose and C clamps and replaced them all myself....
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Old 02-14-2012, 02:28 PM
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Originally Posted by IcemanG17 View Post
http://www.fiveomotorsport.com/impor...uel-injectors/

Or 928motorsports
http://www.928motorsports.com/parts/ljet_injectors.php

They all are pricey..... Typically the high wear item is the little bit of hose from the injector to the rail....I just bought a bunch of fuel hose and C clamps and replaced them all myself....
I think UMC276 is thinking of using off-shelf injectors with a custom made adapter between them and the stock fuel rails.
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Old 02-14-2012, 03:30 PM
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I can get you 8 brand new L-Jet injectors for less than $300. If you decide to go with new style injectors be sure that you buy low impedance injectors.
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Old 02-14-2012, 04:52 PM
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As an alternative to buying new, about 100 bucks to send them to Witchhunter. They flow them and send you a report; you will know if there's a bad injector. Good time to replace the injector hose too.

Last edited by NoVector; 09-09-2018 at 12:49 AM.
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Old 02-14-2012, 05:42 PM
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Originally Posted by Fabio421 View Post
I can get you 8 brand new L-Jet injectors for less than $300. If you decide to go with new style injectors be sure that you buy low impedance injectors.
No problem using a high impedance injector in either a high or low impedance system. The problem is using low in a high system, it lacks the current capacity and fries.

Injectors have improved in the last 30 years, rail type systems are MUCH safer, injectors deteriorate over time, and biggest reason to change them is that the 928 fires all the injectors together. This means all the ones that flow a bit above average run there cylinders rich, and all that flow below average run lean, so lots of benefits in tuning using a flow matched set.

The newer rails can be modified to work on early cars.

Various vendors sell rail stock and a special drill bit that makes the injector fitting in a single pass. Fabrication of the rail mounts seems about the only issue.
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Old 02-14-2012, 06:04 PM
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Speaking of injectors, I have a set from a '84 that have been rebuilt and tested from someone that decided to go with the 928 Motorsport's custom setup with Ford injectors instead. He put the 84 928 motor in his Pantera with twin turbos, too cool.

Anyway, In the past the one or two that failed I'd just rebuild it so I never spent the time to learn about the details between the different year models and their injectors.

My question is, are the injectors the same for the 4.5 and the 4.7?
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Old 02-14-2012, 06:55 PM
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Originally Posted by NoVector View Post
As an alternative to buying new, about 100 bucks to send them to Witchhunter. They flow them and send you a report; you will know if there's a bad injector. Good time to replace the injector hose too.
They're up to $21/ injector (so $170/set), but the idea still holds. I'm about to send off two sets myself.
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Old 02-14-2012, 07:38 PM
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WOW , this is so wrong in so many ways " He put the 84 928 motor in his Pantera with twin turbos,"
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Old 02-14-2012, 10:40 PM
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I've cleaned them myself and replaced hoses about every eight years and always noticed improved gas mileage each time (performance probably too small to notice). Time to do it again hence my questions.

Watching videos of old vs new style injectors (pencil spray vs fine mist) makes it easy to believe that better combustion and mileage, and lower emissions would be achieved.
Placebo effect would make you believe you got better performance also.

There are many good sources and pictures for injector flow rates and sizes. So it may be possible to find a 24lb injector with the proper size injector end to fit stock intake without drilling.

Yes I am thinking of a simple adapter about 1" long with barbs on one end and cup with cutout for hold clip like new style injectors use.

If anyone is thinking of cleaning attached is a parts list for some injectors from Injector Rehab (most rebuild parts available for pennies ex. lower seal $0.36 filter $0.56)
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Old 03-11-2012, 09:37 PM
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anyone know if L-jet is Hight impedance? I'm going Mega squirt and want to use carls injectors that i got...
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Old 03-11-2012, 11:53 PM
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Originally Posted by Ducman82 View Post
anyone know if L-jet is Hight impedance? I'm going Mega squirt and want to use carls injectors that i got...
The L-jet injectors are low impedance.
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Old 01-06-2019, 04:33 PM
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Resuscitating an old thread here. I still have original injectors in my ‘83 but will do a fuel line and injector refresh. I saw another thread about using modern 4-hole injectors in the 32v models. Is there a similar modern injector upgrade for the L-jet cars nowadays? Want a dropin replacement. Otherwise what’s the consensus on the best oem-style replacement injectors?
Cheers,
Rick

PS here’s the 32v thread https://rennlist.com/forums/928-foru...e-ii-info.html
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