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-   -   L-Jet injectors (https://rennlist.com/forums/928-forum/680461-l-jet-injectors.html)

umc276 02-14-2012 12:06 PM

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?

Ducman82 02-14-2012 12:12 PM

i would be worried about how that cup is held down on the injector.

brutus 02-14-2012 12:14 PM

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 ?"

IcemanG17 02-14-2012 12:56 PM

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....

Ethre 02-14-2012 02:28 PM


Originally Posted by IcemanG17 (Post 9276129)
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.

Fabio421 02-14-2012 03:30 PM

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.

NoVector 02-14-2012 04:52 PM

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.

danglerb 02-14-2012 05:42 PM


Originally Posted by Fabio421 (Post 9276641)
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.

Tenshieternal 02-14-2012 06:04 PM

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?

Ethre 02-14-2012 06:55 PM


Originally Posted by NoVector (Post 9276912)
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.

brutus 02-14-2012 07:38 PM

WOW , this is so wrong in so many ways " He put the 84 928 motor in his Pantera with twin turbos,"

umc276 02-14-2012 10:40 PM

3 Attachment(s)
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)

Ducman82 03-11-2012 09:37 PM

anyone know if L-jet is Hight impedance? I'm going Mega squirt and want to use carls injectors that i got...

Fabio421 03-11-2012 11:53 PM


Originally Posted by Ducman82 (Post 9353507)
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.

rjtw 01-06-2019 04:33 PM

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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