Idle Adjustment and tuning (webers)

[Cerbin]

I have a 1970 2.2L w/ dual weber setup...

wht if when i give it gas til around 2500 rpm and it takes like 15 seconds to drop off and come back down??? i tap the gas and seems like im still stepping on the pedal but im not. the linkage is fairly tight and carb linkage is right up against the adjustment bolts but it stays at the same rpms for like i said 15 seconds before dropping off. wht the hell?? is this carb tuning problem?? wht do i do?

also there is mild popping (backfiring), which i "think" is carb tuning as well b/c im pretty sure the ignition timing is pretty close...anyone have any ideas?

any help would be appreciated as im am trying DESPERATLY to get this beast back on the road again!

Patrick O

[jtf914]

I had the same problem with my 914-6. Get the engine to idle around 1000 - 1200 RPM and try using a unisym or synchrometer to check the air flow in each throat (Pelican sells the synchrometer). Adjust the air screws to even out the throats (These are the small screws with the lock nuts).

As a precaution I would record the position of each screw before you start adjusting, this way you can always reset and start from square one. If the engine is idling too fast the synchrometer wont reflect your adjustments very well.

Once that is set you can adjust your mixture screws to try and eliminate the backfiring

Justin Fischer
70 914-6

[BRAINIAC]

The above post is good advice. I'll add that you need to check that your mechanical advance is moving freely. If it is sticky, it will hold the timing advanced and keep the revs up until the springs can slowly pull the weights back in.

------------------
Tyson Schmidt
72 911 Cabriolet
92 C-2 Cabriolet