Another timing question

[bcgreen]

The purpose for checking your timing at 6K is to see if your dist. is working properly. If you're dist. is functioning properly you will not need to make changes to your timing from when you set it at idle. Am I wrong or correct?

[Bob Kontak]

Originally Posted by bcgreen

Am I wrong or correct?

Absolutely correct as long as you check it at 6k rpm.

[Quickstep192]

And what if it doesn't show 30-35BTDC at higher RPMS. Does this point to a distributor problem? (sounds like it). Any info available for diagnosing the advance mechanism in the distributor?

[rwest]

Since we're asking questions, my Porsche spec book(1977) doesn't list an advance spec at all, just an idle spec. Is 30-35 still a good number to go by?

[E Sully]

35' should work fine. This is from the Bentley. Besides the weights moving properly, part of the setting depends on the vacuum pod. If it is leaking or not moving properly it will affect your timing. It is also important to see if the correct distributor is installed. The '77 California distributor has a more radical effect then the earlier ones.

[bcgreen]

Still I am asking, do you still need to check it at 6K, is it really necessary when your dist. is finei?

[E Sully]

Yes.

[Quickstep192]

How does this change when there's no vacuum advance? My car was converted to Webers and now has no connection to the distributor's vacuum advance. Does this mean I should use something other than the 5º ATDC mark as recommended in the tech spec book when adjusting the timing at 900rpm?

[RSTarga]

Just use the 6 k then see if it is close at 900 rpm

[Bob Kontak]

Originally Posted by bcgreen

Still I am asking, do you still need to check it at 6K, is it really necessary when your dist. is finei?

In theory, no, you do not have to check it.

As soon as we say it's all good and bank on what you say, when you experience detonation or lose performance because something in the mech advance is not right, we steered you wrong.

If you had a wimp max advance like in the SC, who cares.

[E Sully]

Originally Posted by Quickstep192

How does this change when there's no vacuum advance? My car was converted to Webers and now has no connection to the distributor's vacuum advance. Does this mean I should use something other than the 5º ATDC mark as recommended in the tech spec book when adjusting the timing at 900rpm?

If the recommended timing at idle is with the vacuum line attached, and you are not using it, then timing at idle will be different. It is also important to check to see if the distributor is the original. If a you or a previous owner changed to a different distributor, things may change also. The most important thing to check is that maximum advance is not exceeded.

[bcgreen]

One last question: can I manually rotate the engine so I can put a paint mark on the notch?

[E Sully]

Yes you can, but only clockwise, don't rotate counterclockwise.

[bcgreen]

Thanks