MFI/ Throttle linkage question

[jm66au]

Hello,

I have assembled the throttle rods on my 911E MFI, but I find that if I respect the recommended length of 114mm for the rod from the centre shaft to the MFI, the regulator lever is open a lot at idle, and it runs very thick (producing a lot of smoke). I understand the MFI should be fully closed at idle, so the only solution is to make the rod shorter. Is this correct, or am I going off in the wrong direction?

Thank you

[tobluforu]

Do not change the rod length. Yes, some will say that you can dial your car in by doing this. I fooled with it years ago, same with adding and removing shims on barometric cell. But ultimately, I put it all back to stock. Something else is wrong. Read edmayos post to get you started.. https://www.early911sregistry.org/forums/showthread.php?48679-MFI-rod-lenghts

[rowingone]

Disconnect every rod but the 114MM one and see where your restriction is . . that 114 is where you need to be.

[nickelplated5s]

Try an air flow meter too.

[Jeff Higgins]

What are you calling the "regulator lever"? I'm assuming it's the throttle bellcrank on the pump itself.

Make sure that the two linkage rods from the throttle bodies are disconnected from the throttle crossbar when you set this 114mm length. Then, with both throttle bodies closed (butterflies resting on their stops) and the bellcrank on the pump resting on its stop, adjust the length of the two rods to the throttle bodies. Adjust them until nothing moves when you snap them on and off the ball pivots.

The two rods from the crossbar have a large range of adjustment, and a large range of allowable variation between them. It is with them that we "take up the slack", or allow for all of the variations in this system.

You should also disconnect the rod that goes down to the transmission bellcrank while you're doing this. It should be the last one you hook up. And, again, nothing should move when you snap its ball cup over the ball.