Vac lines 351 w

Just fyi it’s the moded 351 in the falcon.

Now, I am making sure the vac lines for the distributer and c-6 tranny are properly connected. The distributer is hooked up to the lower vac port on the edlebrok (should it be on the upper or lower? the manual didn’t specify for a 351 ) And the vac line for the tranny goes into the intake manifold.

does everything sound ok?

The reason I am asking is that the rpms are at 3000 when I am going 55, and I am wondering if the tranny is shifting properly.

Do you have anything that explains how to adjust the down shift rod at the carburator for the transmission? Because if this isn’t adjusted correctly, the transmission won’t shift correctly.


The transmission vacuum line does connect to the intake manifold.

On the Edelbrock carburetors the right side (as you face it) vacuum fitting is also manifold vacuum and the left side is ported vacuum. (meaning little/no suction at idle)

If you have the single advance dist. the left side vac. hose will attach to the advance and the right side will be capped.
If you have the dual advance unit the left will attach in the same manner and the right side will attach to the other vacuum fitting on the advance. (that would be the vacuum retard)

On a 3-speed automatic the RPMs could be about right depending on the axle ratio. A ratio in the lower 3’s would make 3000 about right.
Everyone is accustomed to overdrive automatic and manual transmissions so a standard 3-speed really makes the engine sound like it’s screaming.

The only way around that is to change the axle ratio or swap the trans out for an AOD; or both. Hope that helps.

There is only one vac line coming off the distributer. That means it has single advance, correct?

It had a holly on it before, could the person who put the edlebrok on put the hoses on it bacwards because the holly has the vac lines the other way?

The reason I was wondering about the rpm is I asked the prevous owner and he said it would be doing 80 @3000. If, say the tranny never came out of second, would the speed to rpm ratio be correct?

You should be able to feel the shifts in a C-6 transmission. You can see it, too, if you have a tachometer. The revs should drop with every shift. If you accelerate hard, the shifts will be firmer.

BTW, my Ford Explorer with an overdrive transmission would run 3200 rpm at 80. My Toyota Supra runs about 3500 rpm at 80. My old Toyota Pick-up with a non-OD 4 speed ran about 4200 at 80.

I tested the rear end. It is not limited slip, and non-posi. It one spin of the tire turned the drive shaft approx 1 and a half times. what is the rear end? and is it low or high geared?

Single advance is one vacuum line and it should be connected to ported vacuum. Just make sure the hose going to the advance has extremely little or no suction on at a normal idle speed.

You might clarify the part about the previous owner. The owner of the engine or car?
Was the prior owner of this car also the one who put the 351 in?

As mentioned, you should be able to feel the transmission shift through all of the gears. If the transmission is not shifting into 3rd then you might take a look at adjusting the transmission linkage; both the gear lever linkage and the kickdown linkage. Out of adjustment can burn a transmission up.

I’ve got a '79 Camaro with a TH350 transmission (3-speed auto) and from a hazy memory both the 350 and the C6 have about the same final drive ratio.
The Camaro HAD 3:42 gears and it turned about 3200 RPM at 60 MPH.
It got a gear change to 2:56s and it turns about 2200ish now at the same speed.

You might look at the door tag. I think there is a code number on there for axle ratios although I don’t remember them other than possibly “1” denoting a 3:00 ratio. And I’m not certain even on that one.