I found this while searching the net. Very comprehensive and answered all my questions considering most everyone here deals with D-jet. Has anyone ever seen this or is this old news?
http://www.itinerant-air-cooled.com/viewtopic.php?t=7761
I hope this works. I've never added a link before!
Full Version: L-jet adjustment
......looks good Black22, never seen that 1......I've only had 1 D-jet car in all
the decades of my 914 life....I prefer Ljet(10 914's posessed)
the decades of my 914 life....I prefer Ljet(10 914's posessed)
I used that same info to adjust my air flow meter with some great results, i.e better off the line performance, RPM performance. Now I just need to add the Mallory distributor from CFR.
That article should be pinned or stickied to the classic section! Thanks for finding this. 
QUOTE(tim_nd @ Aug 16 2012, 04:25 PM) 
That article should be pinned or stickied to the classic section! Thanks for finding this.
I wanted to see if it was new/ good info and then was going to PM the link to you Tim. Glad you saw it!
Outstanding illustrations!
Great link, thanks
Great link, thanks
Good article, used it in the past.
Couple of years ago I checked out a modified 1.8 ( now for sale in the classifieds) that had just installed the Tangerine exhaust. This car had some added pep; the owner sent me the following email explaining the mods he did. I did drive the car and can verify the changes made a difference:
" Here is the link the owner referenced, and his modifications ( in quotes) :
http://www.opeltuners.com, then select articles Engine Tuning injection specs; About Opel FI system
"The 1975 914 uses the L Jetronic system. It is the best of all the injection systems used in the 70’s and 80’s. You will find the L system on Opals, Range Rovers, Porsche 911’s, BMW and others. You may also use parts off these cars if the pins are the same for the airbox. You can also use the throttle body off these cars if the pins are the same.
In the articles from opeltuners, you will notice that a small change in throttle body and airbox means a large change in available horsepower. The throttle body that is on the 1.8 is good for 160 hp. Just clean up the rough edges inside the throttle and airbox with a grinder and you will be set. Next step is to increase the fuel flow to the engine. You can do this by larger fuel rails, and lowering the full on timing of the injectors to 3000 RPM. Down from the normal 3500 – 3800 stock setting.
I replaced the injectors with stock Bosch; increased the fuel pressure to 43 #; lowered the full on timing of the injectors to 3000RPM. Then I reduced the spring tension in the airbox by a -4clicks and increased the injectors on-time in the lower RPM by one contact slot on the inside dial of the airbox ( inside the tension spring adjuster ) This inside adjuster set the idle to 1000RPM, but made the idle rich so I leaned the low RPM using the bleed screw on the top of the air box. This lets the air by pass the airbox and go directly into the intake after the throttle body, leaning the mixture at low RPM.
So, I have increased the airflow through the engine by exhaust and small mods to the sir box; increased the fuel flow at low and high RPM; and leaned the mixture at idle."
" Here is the link the owner referenced, and his modifications ( in quotes) :
http://www.opeltuners.com, then select articles Engine Tuning injection specs; About Opel FI system
"The 1975 914 uses the L Jetronic system. It is the best of all the injection systems used in the 70’s and 80’s. You will find the L system on Opals, Range Rovers, Porsche 911’s, BMW and others. You may also use parts off these cars if the pins are the same for the airbox. You can also use the throttle body off these cars if the pins are the same.
In the articles from opeltuners, you will notice that a small change in throttle body and airbox means a large change in available horsepower. The throttle body that is on the 1.8 is good for 160 hp. Just clean up the rough edges inside the throttle and airbox with a grinder and you will be set. Next step is to increase the fuel flow to the engine. You can do this by larger fuel rails, and lowering the full on timing of the injectors to 3000 RPM. Down from the normal 3500 – 3800 stock setting.
I replaced the injectors with stock Bosch; increased the fuel pressure to 43 #; lowered the full on timing of the injectors to 3000RPM. Then I reduced the spring tension in the airbox by a -4clicks and increased the injectors on-time in the lower RPM by one contact slot on the inside dial of the airbox ( inside the tension spring adjuster ) This inside adjuster set the idle to 1000RPM, but made the idle rich so I leaned the low RPM using the bleed screw on the top of the air box. This lets the air by pass the airbox and go directly into the intake after the throttle body, leaning the mixture at low RPM.
So, I have increased the airflow through the engine by exhaust and small mods to the sir box; increased the fuel flow at low and high RPM; and leaned the mixture at idle."
......Cool you've did alot of research,trial & error...Jim!, I see you appreciate
that system(Ljet) also.....
that system(Ljet) also.....
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