1.8 L-Jet to 2.0 L-Jet. Any advice? Options

[mapguy]

Howdy,

I have just torn down a bone stock '74 1.8 L-Jet from another 914 with plans to build it back to stock. Plan is to drive my 914 with this engine while I build the original 2.0 the way I want it. I get experience building my first type 4, and get my teener back where it belongs. On the road.

I have the parts available to swap out the crank, rods, and P/C from a '76 2.0 to make it a 2.0 L-Jet. I'm very tempted to do this, as I rarely turn down cheap horsepower! No replacement for displacement, right?

Any land mines I should look out for? Main concern for me is the stock L-Jet system. I understand I might have to tune the MAF for the extra displacement, but I can't find anything discouraging me otherwise. I found an article that details a 3-step process for MAF tuning, but am too lazy to look up the link. Do tell if you know something I don't.

More details:

As implied, stock '74 L-Jet system
Stock '74 1.8 heads (41x34, I believe)
web cam 142/lifters
necessary machine work
Cylinders honed and new rings (I have a set of 94s in excellent condition)
Full re-seal on engine and all peripherals
New fuel lines, vacuum lines, etc etc...

One other thing, I haven't built many engines, but all the ones I've been involved in pop through the intake when first firing them off, and one in particular did it several times before finally lighting off (my old bus engine was a PITA to get running first time). Won't this be dangerous for the MAF on first start? All my experience is with carbed engines. Does this just not happen on FI engines?

Any advice is greatly appreciated.

[ClayPerrine]

I have already done this. It works fine. I have even run 1.8L L-Jet on a real 2.0 motor.

Don't mess with the air flow meter. It will compensate for the extra displacement.

Are you using 1.8 or 2.0 heads? If you use the 1.8L heads, you are limiting yourself on the valve size. You could always have them redone with 2.0 valves. That will help a bunch.

If you use the 2.0 Heads, you will need to be careful about the intake hoses. The runners on the 2.0 have slightly longer tubes. You can compensate by using radiator hoses in place of the intake hoses.

The 1.8L throttle body is the limiting factor. It is way too small for a 2.0L motor. There is a bus throttle body that is a bolt on replacement for it that is much bigger. I saw it in a thread here, but I don't have the link handy.

Everything else in the induction system will be a bolt on, plug and play setup.

Good luck!

[type47]

There is a bus throttle body that is a bolt on replacement for it that is much bigger.

Here is one/are some FS on the Samba. (no affiliation)

http://www.thesamba.com/vw/classifieds/sea...s=throttle+body

If I recall, the 2L engine started in the bus in '79 (maybe 78?) and continued through until '83.5. I looked in a VW online parts catalog for a part number for an '81 Vanagon but it gave no pn and listed it as NLA.