Photos of rear intake ports for more water flow!

[68 Broncoholic]

I finally decided to port the rear intake where water doesn't flow. I drilled and used a pipe tap amd brass fitting so it would seal. Added a T and off to the heater hose with another T. I'll fire it up tomorrow, neighbors wouldn't like a 12am wake up call. %) It should keep the temps down...

 

[Scott M]

what size did you tap to

and what motor is that. the bosses on my windsor were a little narrow so i only went 1/4 NPT, as opposed to 3/8. but yours looks big. also looks like a 302, so it may be different.

also, what fitting do you have on the manifold. i was looking for a 90 degree elbow that would go 1/4 NPT to 5/8 ID hose, but couldn't find shit. so i ended up at a hydraulics store and got a real nice peice but its expensive and sits up high enough to block my throttle linkage.

 

[Madgyver]

I used 3/8" NPT to 1/2" hose barb, It also was a 45 degree adaptor.

 

[68 Broncoholic]

I run a 302 with 289 heads. Its a skinny motor so it wasn't easy using the following...
I used 3/4" heater hose with a 45 deg angle in them. The tap size is 1/2-14 which means the ID of a water pipe (looks to me close to 3/4" threads). I then used a 45/64 drill bit which is between a 5/8 and 3/4 drill bit.
The brass fittings are treaded in almost flush. These large fittings are larger in diameter than the water jacket hole in the head. If you do this do n't tap too far into the intake so the fitting stops before pertruding out the bottom. I was going to go smaller but I wanted more flow. I'll find out today when I finish hooking it up.
Did you all connect to the heater hose that connects to the water pump or the intake?
Guess I should ask which way the water moves into or out of the rear of the motor.

 

[68 Broncoholic]

Ok I looked closer to your photo and see you are connected to the intake manifold just after the thermostat. Wouldn't there be more water pressure if you connected to the heater hose thats connected directly to the water pump?

 

[ricks77eb]

TTT

Wondering which way is best myself......Anyone?

 

[broncnaz]

I'm not 100% sure but I think the fitting on the water pump is a return line not pressure (I think because the heater core is plumbed to get hot water from the manifold then the water runs back to the water pump) which is where I would hook it up to as you want to remove the hot water from the back of the engine. I havent done this mod yet but I'm looking at doing it.

 

[BUCKETOBOLTS]

Doesn't the water come out of the pump into the front of the block, around the cylinders, up into the heads, then to the intake. My temperture control valve is in the hose coming from the intake. This hose feeds hot water to the core. It returns to the pump, so this is where I'd return the rear cross over also.

 

[68 Broncoholic]

Oh boy, 2 answers, who has the correct one??? The water pump sucks water from the bottom radiator hose and into the motor, through the heads, through the intake, past the Tstat and back into the radiator. Sounds to me like the flow wants to suck water out of the back of the motor and not push into it like I thought.
So I would think connecting a T or Y to the intake heater hose side is the right location for return and the pump is the one pushing the water into the heater core. I might find out for sure and let water fly.
I'm thinking of connecting between the heater core and heater control valve so I can turn it on or off with a pull of the knob on the dash.
If its pulling water out of the rear of the motor then a Y would be the best bet so no cross flow problem.
Guess my question still stands, does water want to enter (push) into the rear of the motor or exit by pulling?

 

[BUCKETOBOLTS]

Start the engine and as it warms see which hose starts to warm first. That will tell you which hose is supplying the water for heat. The other will be the return.

Okay here's another theory. If the pump feeds the heater core from the radiator, why not pump that cool water to the rear? The warmest water will be in the heads. On a stock intake with a rear passage the water just circulates from side to side.

On a LT1 the intake has no water at all. They call it reverse cooling. Take the cool water and pump it through the heads first then the block. I believe the Ford Modulars work the same way.

 

[Madgyver]

The whole idea to running the hose at the back of the heads is to provide circulation (spell?ng). The 351w intake doesn't have the coolant passages so the coolant dead ends at the back of the heads= no flow. So by adding the passages, It makes for more efficient cooling.
Look at it this way, It's like San Francisco Bay..... ;D

Is my spelling correct? ?:?

 

[68 Broncoholic]

Ok I got it figured out.
We can attach it in any of the two hoses as long as a Y fitting is used so it draws (pulls/sucks) the water out of the back of the motor/intake.
So if you want to connect to the water pump hose (its pushing water) you will need the Y in the direction so both the rear intake ports like I made and the water from water pump are moving in the same direction. The causes a suction.

Or if you don't want it going thru the heater core connect the Y just after the heater control valve so it enters on the top of the manifold. Just make sure the Y is going the correct direction and it will suck the water...

Here's a quick sketch...

 

[68 Broncoholic]

OK... I talked to Edelbrock tech support cause a friend said they have an intake like the mod I did if you don't want to drill and tap (#3721).
Scroll down to view... http://www.edelbrock.com/automotive_new/mc/manifolds/ford_sb_perf.shtml

This is for EGR carbs only but its an option.

He claims what I did is a usual modification these days and works well.
He even said there is no need for a Y (drawing water)when it enters the heater hose cause there is enough water pressure that will be pumping out of the back of the engine I could use a T. He likes the idea of the Y and thought it would help so you don't get cross pressure. They have always used T's with good luck.