Syncing webers Options

[pitr256]

Hey all,

Got my 914 running to the point after sitting for 15 years where I can actually drive around the block. Trying to synchronize the webers and noticed that when I put the unisync over cylinder #1, the engine's rpms rise to over 2000. Noticed the same on cylinder #6 but not as pronounced. Opening up the unisync all the way still causes the reduced air to the intake to cause the rpms to rise.

Is this normal?

I have the idle and air mixture screws at the default settings and would try adjusting but it developed an oil leak under the oil filter somewhere so have to fix that first before tuning more. This car has been 2 steps forward, 1 step back all summer. Almost there though.

Thanks for the insights.

Peter

[pitr256]

Thanks for all the tips. I am using the older unisync tool. Maybe it's time to invest in a newer version.

It doesn't seem right to me that the rpms would rise when the airflow is decreased over a particular cylinder head but my "working" theory (and by working meaning only what I've learned in the last 2 months working on these webers and reading about them) is that as the air is reduced, the vacuum is increased and therefore causes more fuel vapors to be injected in to the engine. Or it could be a vacuum leak is part of the issue though I have checked for those and can't find any.

The engine was completely removed and rebuilt by a local Porsche shop so the valves are set. The carbs have been completely stripped and soaked in carb cleaner for hours. I think all the passageways are clear as adjustments can be made on the idle and air screws.

I installed size 75 idle jets that I had and that seemed to help out tremendously with my stuttering past 2500 rpms while driving. I'm going to take out the emulsion tubes and let them soak overnight and put in a extra set of F3s I have to see if that helps.

Thanks again,

Peter