Tonight I took my intake off. I will be putting on a Weiand polished intake. First of all I did not expect this thing to way as much as it does! It's got to be about 50 lbs. Anyway when I took it off I noticed that my rear two water jackets are opened. Not closed like many other 350's. Also the one port I guess for the EGR? was blocked up with loads of thick carbon. Had to use a hammer and chisel it out with the shop vac on to get all the pieces. Third - My motor actually has holes for gasket pins on either end. I have never seen this either. Do I have a real problem with all that carbon? And the rear water jackets being open? They look real bad inside, Just the rears. Thanks...



this is it cleaned up.

 

I believe the rear water jacket on the heads is always open but blocked on the intake manifold, if I'm wrong I'm sure someone will correct me. The holes on the ends of the block are normal and are used to install the front and rear manifold gaskets which no one uses anymore, most people just lay a 1/4 bead of silicon on each surface instead of using the gaskets. The carbon can become a problem if you are still using a EGR valve in the system. Hope this helps you out...Tim

 

As far as the water passage in the rear goes, yeah, it's there, but there is no corresponding passage in the intake manifold. You are gonna kick yourself when I tell you why! Think about it: The heads are made to be able to be installed on either side of the engine...............yeah!!! That's right, if you take the head off the driver's side and put it on the passenger's side, the rear of the head becomes the front of the head. So, that explains that.

As far as it being heavy.......well, I guess you have never hefted a cast iron Ford FE intake manifold! I swear, it's gotta be 1/4 of the weight of the whole engine!!! I'm exaggerating, but you get the idea. Even if your new aluminum intake didn't increase performance, it would still be worth doing just for the weight savings.


Scott

 

Dont worry yourself.
There is nothing going on there that will be a problem.

 

I just put it on a scale. 42.6 Lbs!! New intake 15.0 Lbs. I never did put my exhaust manifolds on. I assume there's another savings of about 20 Lbs. Compared to the headers.

 

What would cause all that carbon??

 

Just a collection of exhaust 'junk' accumulated over many years. Just remove all that crud and check out EGR function (or eliminate it, if you don't have any emission checks to pass).

 

My carb. has two vacum lines that connect to the old manifold. The new one does not offer a place on the side for a vacum hook up. What should I do? One line is for the choke, the other connects to the secondaries.

 

Lovely timing as I'm looking to remove my intake. I was however going to just clean it up and put my stock intake back in. Is the Weiland a drop in replacement intake with a Rochester carb? Why are you changing intakes (other than the weight savings)?

 

So it's commonly accepted practice to not use the rubber front and rear gaskests that come with the intake manifold kits?

 

[QUOTE=daanbc;1578836030]My carb. has two vacum lines that connect to the old manifold. The new one does not offer a place on the side for a vacum hook up. What should I do? One line is for the choke, the other connects to the secondaries.
QUOTE]

Bubba put a 78 L48 Auto carb on my 74. The manifold is the original 74. To overcome the different choke setup, I just bought an electric choke to fit in the 78 q-jet choke housing, and blocked the vacuum ports off.

 

Saving weight over the heavy junk stock intake is a performance gain 10Xs over.
And no one uses the end gaskets any more.

 

The carbon built up over time just because that intake area is colder than the exhaust. When using an egr it cna get mostly blocked and promote pinging on pump gas. If the intake still has the crossover passage, I would fill it and use a blocked intake gasket. You can use block fill or plaster.

If you don't have headers on, remove or disable the exhaust heat flapper.

The choke tubes for the carb can be eliminated altogether and cap the port going to the choke housing. You can adjust the black thermo cap to keep the choke butterfly full open when cold and not use a choke or replace it with an electric choke thermostat from a later year truck or any parts store.
If not using the choke, just pump it a couple times to start, feather it for about 15 seconds and then let it warm up at idle.

The water ports should be cleaned out. There is no flow there, so it cruds up. After your engine is assembled, I would disconnect radiator hoses and cap off at engine.Directly connect a garden hose to the top of the intake. Remove the two block plugs and flush out the block until clear. Once the block is clear, then do it again with the rad connected until clear.
When installing the heater fitting, put teflon tape on the fitting and also put a bit of antisieze on the intake threads.

I like to use SS bolts in the intake, but make sure the lengths are correct if changing, too long and they bend pushrods.

All this works very well in S Florida because it hardly ever gets below 60° and usually daytime temps are around 90.

 

Yes, most engine builders no longer use the rubber gaskets due to the fact that have a bad habit of leaking. A good silicon seal is all that is needed.....Tim

 

If you install a new set of Vortec style heads, you won't have to worry about the Carbon build up as there is no exhaust cross over. Looks like a typical 35 year old engine to me. No worry's Al

 

Thanks to all... noonie what about the vac. that goes to the back of the carb. looks like it goes to the secondaries. Can this be plugged too! Is it normal to block off that one port?

 

That's really a filtered air intake for the heated choke air tube system, not vacuum.
Cap it off with a rubber cap.

Just for fun, post a pic of the bottom of the new intake. Just want to see the crossover, if it has one.

 

Here ya go. It does have the cross-over. My gasket kit has the block off plates in it. I will use them. What do ya think.

 

Looks good.
I would fill it and still use the block off plates.
Years ago, we would stuff it full of alum foil.

BTW, throw all your old stuff in the attic, just in case emission testing comes back. The gov met with California officials a while back about this. Cali testing here would be scary.

 

Yeah I have been keeping ALL the stuff I have replaced. Starting to run out of room. LOL So your saying to fill the ports on the new intake? Correct? Then also use the block off plates.