Crab distributor question

[Daveyjonez]

Hello All:

I just want to make sure I have my ducks in a row- I have dressed the front of my 8ba with early pumps, cam, 2 bolt timing cover, pulley, etc. I am going to run a stock rebuilt crab distributor, w vacuum brake. I need to run vacuum to the manifold from the timing cover, what is the fitting for the timing cover- where can I grab one??

Thank You!
DaveAAA4B634-CFA9-47E4-8B59-ABFE15540848.jpg

[petehoovie]

Originally Posted by Daveyjonez

Hello All:

I just want to make sure I have my ducks in a row- I have dressed the front of my 8ba with early pumps, cam, 2 bolt timing cover, pulley, etc. I am going to run a stock rebuilt crab distributor, w vacuum brake. I need to run vacuum to the manifold from the timing cover, what is the fitting for the timing cover- where can I grab one??

Thank You!
DaveAttachment 509105

[Lawson Cox]

The vacuum line runs FROM the intake to the timing cover, if that really matters. 3rd Gen has a pre formed line for that. Comes with all the proper bends, curves and fittings. Good luck.

[Daveyjonez]

Originally Posted by Lawson Cox

The vacuum line runs FROM the intake to the timing cover, if that really matters. 3rd Gen has a pre formed line for that. Comes with all the proper bends, curves and fittings. Good luck.

Great, thanks-I will give them a shout tomorrow- yes, I understand vacuum signal comes from manifold, not the other way around😀

[tubman]

That looks like an 8BA intake manifold. Unless the pre-formed line from Third Gen is a specialized piece, I'll bet you'll have to make your own as there is no provision for manifold vacuum on an 8BA (other than the wipers). You'll probably have to "tee" off of that or drill and tap a new port (probably the best way to do it).

[Daveyjonez]

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Originally Posted by tubman

That looks like an 8BA intake manifold. Unless the pre-formed line from Third Gen is a specialized piece, I'll bet you'll have to make your own as there is no provision for manifold vacuum on an 8BA (other than the wipers). You'll probably have to "tee" off of that or drill and tap a new port (probably the best way to do it).

Thanks- yes, the manifold is an edelbrock regular dual, it does have a port under the back carb, I’m sure I will have to make some stuff to get it all sorted. Really just wanted to make sure I get the correct fittings.

[Lawson Cox]

Just darn, I am just not very observant nowadays I guess. I seem to be fixated on a stock flathead 60HP presently.

[cas3]

Tubman is correct, thats an 8ba manifold. So...what are you going to do about the difference in the way the block breaths? No room for the front breather tube with short water pumps, is there ?

[Mart]

Hello.
Have you used original water pumps?
Have you used 59A type cam drive gears?
Have you sealed the water bypass hole in the left hand bank?
Have you sealed off the road draft vent in the oil pan?
Have you made provision for PCV or other type breather?

These items all MAY be relevant to your build.
I covered most of these jobs in a recent build series in my videos.
This is the first part:

https://youtu.be/LsDXGco2E_8

It is a complete build series so you will have to wade through all the videos to find the relevant parts.

Mart.

[Daveyjonez]

Originally Posted by cas3

tubman is correct, thats an 8ba manifold. So...what are you going to do about the difference in the way the block breaths? No room for the front breather tube with short water pumps, is there ?

pcv

[Daveyjonez]

Originally Posted by Mart

Hello.
Have you used original water pumps?
Have you used 59A type cam drive gears?
Have you sealed the water bypass hole in the left hand bank?
Have you sealed off the road draft vent in the oil pan?
Have you made provision for PCV or other type breather?

These items all MAY be relevant to your build.
I covered most of these jobs in a recent build series in my videos.
This is the first part:

https://youtu.be/LsDXGco2E_8

It is a complete build series so you will have to wade through all the videos to find the relevant parts.



Mart.

Drake pumps, sealed bearings- no need to seal extra hole up top in block (water pump).

Correct 59a Cam gears for proper thrust

Holes in block sealed with welch plugs

Not sealing the pan- going to run a pcv setup in the road draft hole in the intake to vacuum (in the intake).

Did you come up with a spiffy way to pull vacuum signal to the timing cover for your original crab??

[Tony, NY]

I don't have a vacuum line to my crab and runs great. Do a search and you'll see others have done the same. Back off the brake.

[35fordtn]

As Tony NY indicates, the Vacuum brake is really not needed with the octane level of todays fuel. I run the line for appearance only. The purpose of the Vacuum brake is to retard timing on low vacuum conditions such as climbing a steep hill where spark knock prevails. With the 87 and up octane fuel on our low compression flatheads spark knock is a rare instance. Essentially the vacuum brake takes away performance. If we ever get back to 65 octane fuel of unless you are running a suoer high compression or a supercharger, it is not needed.

I run the plunger for the vacuum brake at 1/2 turn in so it has just enough tension to bring back the mechanical weights to static retard at idle.

[Daveyjonez]

Thanks very much guys- I’ve read a lot about vacuum brake no vacuum brake- I know Bubbas had indicated it should be used. Makes sense that the higher octane/ low compression reality renders the advance brake not necessary.

Thanks Again!

[JayChicago]

Bubba also told me that the brake should be used, needed for ease of starting. He said it should be adjusted with light tension, just touching the weight. And now Michael's post #13 explains why.

[Mart]

Originally Posted by Daveyjonez

Not sealing the pan- going to run a pcv setup in the road draft hole in the intake to vacuum (in the intake).

You're using an 8BA pan. I only have exerience with French blocks which need the road draft vent hole blocking off to use a 59A type pan.

Did you come up with a spiffy way to pull vacuum signal to the timing cover for your original crab??

Just the standard type 3/16 tube with salvaged brass fittings. I have also used modified brake bleed nipples with rubber hose but I wouldn't call it spiffy.
FWIW I always run vacuum and leave the brake just very lightly dragging.
Mart.

[Daveyjonez]

Originally Posted by Mart

Just the standard type 3/16 tube with salvaged brass fittings. I have also used modified brake bleed nipples with rubber hose but I wouldn't call it spiffy.
FWIW I always run vacuum and leave the brake just very lightly dragging.
Mart.

Thx Mart!

[rotorwrench]

Generally, the vacuum advance gives better fuel mileage over the long haul. Around town, it likely won't affect much. If the vacuum system leaks then it will cause a lean condition. The vacuum line fittings were used as long as Ford still used the metal tube set up up into the 60s. Eaton still makes the 6100 series flare fittings. The flared seat adapter to the pipe thread fitting is also out there if a person wanted to connect it in similar fashion to what Ford used on the front mounted Mallory design distributor.

[FlatheadTed]

We just had this problem were this 38 had a no port front connection we fitted the two bolt front cover and took a connection to the Vacuum cv port under the carb ,the idle was pretty rough ,so i squeezed of the rubber hose cv connection . The engine smoothed out ,it appeared to be a leaking 2nd hand one ,Ted

[19Fordy]

Davey: Are you sure you want to use an intake manifold where the generator mount is offset towards the driver side and not centered?