L-jet with a 2200 or 2258, Has it or can it be done? |
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L-jet with a 2200 or 2258, Has it or can it be done? |
JamesJ |
Dec 9 2023, 10:51 AM
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#1
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Member Group: Members Posts: 229 Joined: 30-April 20 From: Sunnyvale, CA Member No.: 24,202 Region Association: Northern California |
Hello World,
Has anyone successfully been able to pair(dial in) a modified 914 L-jet system with a 2200 or 2258? I am looking into doing this for my street car and am aware that the AFM will need to be modified. I have a 52mm throttle body with a modified throttle actuator so the operating arm will work with the L-jet and will fit the stock plenum seal. Will I need bigger fuel injectors than my new 2.0 injectors? If so, which ones? What else do I need? I did a Google search using key words, but was not able to find any previous threads on this topic. Any advice or thoughts would be appreciated. |
Root_Werks |
Dec 9 2023, 11:15 AM
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#2
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Village Idiot Group: Members Posts: 8,508 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
I did a 2.0 L-Jet that worked very well. Would think a 2.2 would also work as long as you used a correct combo of parts. There should be a lot of resources on the Samba, Bus folks.
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Dave_Darling |
Dec 9 2023, 12:57 PM
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#3
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914 Idiot Group: Members Posts: 15,063 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
You might check to see what other ~2.2 liter 4-cylinder engines used L-Jet, and scrounge parts from those. Going to be harder to find in junkyards, though, as those will all be much older cars than the first time I heard this advice...
--DD |
Superhawk996 |
Dec 9 2023, 01:07 PM
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#4
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914 Guru Group: Members Posts: 6,598 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
In this day and age - Microsquirt. Not the answer to OP is seeking but 100% capable of dealing with displacement, cam changes, compression ratio changes, and overall changes in volumetric efficiency that L-jet is going to struggle with.
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Geezer914 |
Dec 9 2023, 01:24 PM
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#5
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Geezer914 Group: Members Posts: 1,797 Joined: 18-March 09 From: Salem, NJ Member No.: 10,179 Region Association: North East States |
Enlarge the plenum opening for the throttle body using a tailpipe expander. You can use a 2.0L Vanagon gasket as they used a 50mm throttle body.
There are articles on you tube on how to richen up the AFM using an AFR meter. You need to have a bung in the exhaust. |
Montreal914 |
Dec 9 2023, 01:31 PM
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#6
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Senior Member Group: Members Posts: 1,725 Joined: 8-August 10 From: Claremont, CA Member No.: 12,023 Region Association: Southern California |
Also a lot of engine/FI info on shoptalkforum.com
Please share your progress which ever direction you decide to go with. (IMG:style_emoticons/default/smile.gif) |
914werke |
Dec 9 2023, 03:44 PM
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#7
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"I got blisters on me fingers" Group: Members Posts: 11,029 Joined: 22-March 03 From: USofA Member No.: 453 Region Association: Pacific Northwest |
Probably the displacement will have less impact than the cam used to fill those cylinders.
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porschetub |
Dec 9 2023, 04:18 PM
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#8
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Advanced Member Group: Members Posts: 4,754 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
Hello World, Has anyone successfully been able to pair(dial in) a modified 914 L-jet system with a 2200 or 2258? I am looking into doing this for my street car and am aware that the AFM will need to be modified. I have a 52mm throttle body with a modified throttle actuator so the operating arm will work with the L-jet and will fit the stock plenum seal. Will I need bigger fuel injectors than my new 2.0 injectors? If so, which ones? What else do I need? I did a Google search using key words, but was not able to find any previous threads on this topic. Any advice or thoughts would be appreciated. That should be a great combo,go to the larger motor and get the most from the larger throttle body ,L-jet can be run on larger capacity motors because the AFM is controlled by airflow and will self adapt to the volume of air working the air gate . Never heard of any modification you can do to them for flow and it's not required,if you have a good AFM don't mess with it , the only one I ever adjusted was to correct " rolling idle" caused by a "hot " street cam in a Golf 2.0 engine I built running cam chip . Pretty certain stock injectors will cover your needs . I recently fitted a 2.0 16V to replace worn out 1.8 16V in my VW Corrado ,I just swapped the old K-jet system from the 1.8 to the 2.0 and it runs and drives very well this system is controlled by airflow also but is full mechanical with a small basic ignition computer however base principal is the same as L-jet . What cam are planning to run ? , believe this would need to be reasonably mild to avoid rough idle which the AFM won't play well with . The sum of all parts in good condition ,the right cam and exhaust should yield a strong motor with good torque , there are most likely some that have done this conversion and can correct me ?,cheers. |
porschetub |
Dec 9 2023, 09:40 PM
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#9
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Advanced Member Group: Members Posts: 4,754 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
Enlarge the plenum opening for the throttle body using a tailpipe expander. You can use a 2.0L Vanagon gasket as they used a 50mm throttle body. There are articles on you tube on how to richen up the AFM using an AFR meter. You need to have a bung in the exhaust. He is running a 52mm TB not sure you could do that ? ,anyway an AFM is very carefully set from factory and one mistake with quadrant spring will render the part useless ,the signal from a good (condition ) AFM should input a signal to the computer to injectors to alter duty cycles ? . Cam choose as mentioned is a key point ,it has to match the increased flow but be able to hold a reasonable idle without causing issues with the AFM . |
Geezer914 |
Dec 10 2023, 06:20 AM
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#10
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Geezer914 Group: Members Posts: 1,797 Joined: 18-March 09 From: Salem, NJ Member No.: 10,179 Region Association: North East States |
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VaccaRabite |
Dec 11 2023, 11:52 AM
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#11
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En Garde! Group: Admin Posts: 13,616 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
IMO - why bother?!
L-jet is archaic. It uses NLA parts. No one can easily tune it. And you are restricted to a very mild cam which makes a big engine kind of a waste. Its not like you are preserving a stock engine. There are so many good modern fuel injection systems on the market in either kit form or fully DIY. Microsquirt if you want to go DIY. Or Holley Sniper if you want something a little more baked. Or Holley Terminator X (which I am currently running). I think you will be unhappy in the long run trying to get L-Jet to work with any 2.2-2.3 engine. Zach |
porschetub |
Dec 11 2023, 01:55 PM
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#12
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Advanced Member Group: Members Posts: 4,754 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
I am running a 50 mm Vanagon throttle body on my 2056. Moved the large wheel in the AFM 2 notches to get the AFR from 14.2 to 13.2. Sir you are correct ,went thru my notes for VW AFM setting and found that I did change the spring tension on the wiper quadrant on the motor more than I mentioned . What was your final cam choice ? , seems the PO may have an issue there as 914werke mentioned. Appears the larger TB is a useful gain even on a mild engine ,I have the stock one and its pretty small. (IMG:style_emoticons/default/beer.gif) . |
VaccaRabite |
Dec 11 2023, 03:52 PM
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#13
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En Garde! Group: Admin Posts: 13,616 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
The biggest throttle body you can easily run is the GoWesty TB which is around 52mm. I had one running on my 2056.
Not only is it larger and allow more air, but it is new, and does not have to be rebushed in order not to leak. Its a really solid unit. I have a thread here on the transfer. it was very easy. One thing you will need to do is open up the intake plenum or you will have the same restriction you would have with a stock TB. I had my plenum opened up slowly at an exhaust shop, and then tapped it into the right shape with a small chasing hammer. Used a thin smear of RTV to place the TB instead of trying to find a gasket that would fit. The outcome was that I was able to open a whole new row of bins at the top end of my rev range. Zach |
JamesJ |
Dec 12 2023, 12:01 AM
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#14
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Member Group: Members Posts: 229 Joined: 30-April 20 From: Sunnyvale, CA Member No.: 24,202 Region Association: Northern California |
Thank you all for your replies...keep them coming, especially if you have any experience with the combo of 914 L-jet with larger displacement.
Interesting that folks have mentioned modifying the AFM & using a larger TB, but still...all done on nothing larger than a 2056. To answer your question, Zach, my first build that went south(geographically & literally) was a 2056 and I had purchased new injectors and had the AFM & AAR rebuilt. I am attempting to preserve that small investment while considering larger displacement on the re-do build. |
JmuRiz |
Dec 12 2023, 08:34 AM
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#15
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914 Guru Group: Members Posts: 5,514 Joined: 30-December 02 From: NoVA Member No.: 50 Region Association: MidAtlantic Region |
You need something like this...
https://www.youtube.com/watch?v=https://youtu.be/K_A7rPcvYCM?si=zi50x8GaHJNef-mh Kidding...but I know where you can get this exact setup (IMG:style_emoticons/default/wink.gif) |
Geezer914 |
Dec 12 2023, 10:28 AM
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#16
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Geezer914 Group: Members Posts: 1,797 Joined: 18-March 09 From: Salem, NJ Member No.: 10,179 Region Association: North East States |
I am running a 50 mm Vanagon throttle body on my 2056. Moved the large wheel in the AFM 2 notches to get the AFR from 14.2 to 13.2. Sir you are correct ,went thru my notes for VW AFM setting and found that I did change the spring tension on the wiper quadrant on the motor more than I mentioned . What was your final cam choice ? , seems the PO may have an issue there as 914werke mentioned. Appears the larger TB is a useful gain even on a mild engine ,I have the stock one and its pretty small. (IMG:style_emoticons/default/beer.gif) . I am running a 9550 Web cam. |
914_teener |
Dec 12 2023, 12:03 PM
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#17
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914 Guru Group: Members Posts: 5,250 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
What's your budget?
You'll start running into cost benefit tradeoffs with larger displacements in a type 4 above 2 liters. Just saying and yes from experience. I've seen short stroke 2.0 type IV's with L-Jet just smoke the tires on a 914...big bore short stroke engines just pushing the limits of their VE's. To get that same efficiency in a type IV above 2 liters will take more dollars on a log log curve above 2 liters. Good luck....anything is possible. |
VaccaRabite |
Dec 12 2023, 01:48 PM
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#18
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En Garde! Group: Admin Posts: 13,616 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
What's your budget? You'll start running into cost benefit tradeoffs with larger displacements in a type 4 above 2 liters. Just saying and yes from experience. I've seen short stroke 2.0 type IV's with L-Jet just smoke the tires on a 914...big bore short stroke engines just pushing the limits of their VE's. To get that same efficiency in a type IV above 2 liters will take more dollars on a log log curve above 2 liters. Good luck....anything is possible. It seems like the 2258/2270 is the sweet spot for a bunch of different reasons. Piston size is staying within reason at 96mm, so the jugs are not super thin. You can still have a well cooled engine with cast cylinders. 2258 is a combo that I'm getting more familiar with (seeing that I am now driving one). Zach |
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