Currently I have a '75 1.8 Liter with L-Jet FI in my car that has been performing well. I recently purchased a '74 2.0 Liter (4 cylinder GA) motor that came with dual Weber 40 IDF carbs. I have not yet determined if the cam in the 2.0 Liter motor has been switched out with one that is suited to the carburetors. If I find an original FI compatible cam inside, I might want to consider swapping over the L-Jet from the 1.8 Liter to the 2.0 Liter and selling the dual Webers. So my question is how simple is it to swap the L-Jet over from the 1.8 Liter to the 2.0 Liter motor. I'm sure this has already been addressed in the forum, but my various searches came up with nothing. I'm thinking that I'll need 2.0 Liter manifolds and possibly 2.0 Liter injectors and that everything else might just come over and bolt on. Any and all advice welcome.

You need the 2 liter runners to match the heads. They won't line up right with the L-Jet plenum but can be connected with the proper diameter Silicone tubing instead of the stock hoses.
D-Jet injectors don't work with L-Jet.

You pretty much need the 3 bolt manifolds from the 2.0 D-jet system (HERE) & the entire L-jet kit from the 1.8L (sans its manifolds) including its injectors
The flow rate for those is withing the envelope of the stock 2.0L
Dan Root did this conversion on his a few yrs back and was a pretty respectable runner!

So why not source and install the correct 2.0L injection? Lots of reasons why this is the best approach.

Sounds quick and easy to slap on what you already have, but why create a Franken-motor?

It's a race car that's already a "FrankenCar", 1972 car with a Chalon body and a '75 1.8 L-Jet now. Might be nice not to have to re-jet carbs when I race at different elevations. In my opinion, the L-Jet is way simpler to set up and troubleshoot than the D-Jet, and I already have the L-Jet. I could sell the Webers and use the money to buy a nice new FI harness for the L-Jet and then it would be solid as a rock. It all depends on what cam is in the 2.0 Liter. Thanks for all the input.

a big race cam and carbs will make more power... as long as your there......

As the car was originally an L-jet, and if the wiring plug ins, double relay, etc. are still intact for that, it's probably easiest to stick with L-jet. That is what I did when I had my 1.8L motor swapped to a 2056 motor using the 2.0L runner setup above and it works great. It is also fairly easy to adjust the Air Fuel Meter for the increased displacement, especially if you have an air/fuel ratio gauge or the plx multigauge one that works with a smart phone (thanks for the tip on that I found on this site). Here are good instructions that explain L-jet AFM adjustment for even a non-mechanic like myself https://www.itinerant-air-cooled.com/viewto...f=50&t=7761 and will get you close to the correct settings. Some people on this site have also increased the size of the throttle value for performance increases and there are threads on that.

BTDT it works good.

While I tend to agree with you Jeff its his car he already has the L-jet kit and
Franken-motor is a little harsh considering the 912E

L-Jet is a good fit for a 2.0L. Done it multiple times, as the spare motor for Betty's car is the 2.0L that was originally in my car.

Get some injectors from a 280ZX. They are the same as the 912E injector, and work great with a modified engine under the L-Jet system. If you are keeping it long term, put a bigger VW bus throttle body on it too. The extra airflow will wake up the engine.

Good luck.

I liked L-Jet on the 2.0.

Conversion starts around page 8:

http://www.914world.com/bbs2/index.php?sho...4990&st=140

Definitely try to source the Vanagon throttle body, they came in two sizes, get the bigger one. I found them on both eBay and The Samba. It’s a direct fit and, there’s a thread on this in the garage
See: https://www.gowesty.com/product/electrical/...-throttle-body-