What to do with vacuum adj on distributor, and what to do with oil breather

[hienz]

Hi,
I am converting my 1975 911s from CIS to Webber.
What should I do with the vacuum hose that hooking up to the distributor?
Also, what should I do with the oil breather?
Thank you so much in advance.

[Lyndon302]

Oil breather goes into the rain hats. Comes in the kit

[AndrewCologne]

What should I do with the vacuum hose that hooking up to the distributor?

As you switched from CIS to carbs, there shouldn be any vacuum hose left leading to the distributor.
BUT to get the best out of the new mixture control by the carbs you should think about at least recurving your distributur so the ignition timing will be optimizied though the whole rev range.
Another option would be an electronic iginiton timing control set up.

[Flat6pac]

The vacuum hose on a 2.7 is a vacuum retard, not necessary with carbs
Bruce

[hienz]

Thanks all for valuable info. Now I must modify my engine breather so it can breathe.
I bought a small cone style filter for breather. Now where is the best place for this tiny cone filter so driver won’t smell the oil?

[hienz]

Originally Posted by Lyndon302

Oil breather goes into the rain hats. Comes in the kit

I do not have the rain hats. I use the tiny screen which snap on top of velocity stack lips.

[stownsen914]

I assume you mean your oil tank breather and not the crankcase breather? The engine should vent to the tank, and the tank to atmosphere.

If you vent your crankcase directly to atmosphere, you risk spraying oil all over the engine bay.

Even from the tank, you're better off with a catch can in case the tank spits oil.

[hienz]

Sorry. I did not think that far about venting crankcase directly and risk spraying oil all over the engine bay. Thank you Stownsen914 for deeper thought. I will have to use the original catch can
to vent the crankcase. Thank you again.

[Jeff Alton]

A small filter on the oil tank breather outlet or route to catch can. I can't remember the last time I say a setup that vented to the rain hats, even though the parts are included in the kits from PMO. We toss them in the garbage....

Cheers

[hienz]

Thank you everyone for info. I am ready for my 1975 modification.

[Jonny042]

1978 SC 3.0L - I locked mine out and covered the hole....

[hienz]

That would make my engine bay looks very clean. I would like to do the Jonnny’s way.
Thanks Jonny.

[chrismorse]

If your car is frequently used on the street, (not just race), retaining the vacuum advance could be of considerable help getting better fuel mileage. My old autoshop instructor called the vacuum advance, "a load compensating device".
More to your point, I would recommend getting your distributor advance "re-curved" to get the best power and economy. Talk to those folks regarding the costs/benefit of retaining the vacuum advance if the car will be mostly street.

Ventillating the engine from engine to dry sump tank and from tank to a catch can, then, vent the catch can to a small filter. If the car has significant mileage, you might want to keep an eye on the engine compartment around the filter to see if the filter is catching all/enough of the oil.

The velocity stack screens look ZOOMIE, but do nothing to keep the dirt and dust out of your engine. This dirt will cause more rapid engine wear and not appreciably help mileage/performance over good filters.
chris