L-Jet Idle on new build with 9550 Options

[andreic]

Hello,

I am just finishing up a new engine build for a 1975 914 1.8L.

The engine is mostly stock, except for the fact that I am using 96mm cylinders (1911cc total) and a Raby 9550 cam. Using the stock L-Jet fuel injection.

I managed to get the engine started, broken in (25 minutes at 2500 RPM), all is well. I also adjusted the timing as per standard instructions (showing the L-Jet mark on the fan at 800 RPM with vacuum lines removed and plugged). The engine is accelerating smoothly and seems to have good power throughout the whole RPM curve (without a load, though, I am testing it outside the car).

The only thing not working is the fact that it will die (stall) at idle. Does not matter if it is hot or cold. I tried the idle adjustment screw on the throttle body, and while I can perhaps get the idle up to 500 RPM with the screw all the way out, I can't get it to 900. And at 500 RPM it is very shaky.

Any suggestions as to what I can do? I knew that using the 9550 cam with the L-Jet was going to give me trouble, but I hope there is some way to fix this. Tomorrow I want to check if there are any vacuum leaks, but I suspect there are none, I was quite careful with all the vacuum lines. If the problem is the cam, can the throttle be perhaps modified to let in more air at idle?

Thanks,
Andrei.