WHy do peeps connect the rear water ports on an intake??

[396_WAYS_TO_SPIT]

I was browsing through some pics and noticed that people are connecting the rear water ports. Is this for better cooling of the motor??? :confused:

[SmokinLowriderSS]

According to my Air Gap manifold, it is supposed to eliminate a "dead spot" in the water flow at the back of the heads to cool them more evenly. Couldn't hurt anything so I hooked 'em up.

[Wicked Performance Boats]

Helps eliminate air pockets in rear of engine Budlight

[Moneypitt]

I was told by Bud Gilbert, (RIP), not to use them. They may work in a vehicle with a closed system, but without the pressure controling the flow, like in a boat, they will create hot spots in the cylinder heads because the water doesn't return to the front, taking heat with it. Fast moving water will not absorb the heat, simular to removing the thermostate from your grocery getter, only to find out it needs some restriction to properly cool the engine......Just my .02....MP

[Fiat48]

If it ain't broke then don't fix it.

[Wicked Performance Boats]

I was told by Bud Gilbert, (RIP), not to use them. They may work in a vehicle with a closed system, but without the pressure controling the flow, like in a boat, they will create hot spots in the cylinder heads because the water doesn't return to the front, taking heat with it. Fast moving water will not absorb the heat, simular to removing the thermostate from your grocery getter, only to find out it needs some restriction to properly cool the engine......Just my .02....MP
Sorry to here about Bud Gilbert. We've lost another great one. However I disagree. If you have the crossover hose between the back intake ports, all it will do is help create an even pressure flow forward through the heads. It can't hurt. Budlight

[Moneypitt]

So you just connect the two heads in the rear, and still exit from the front. That should work as the water still has to pass through the whole head to get out. I can't help but believe if there was an advantage to adding these ports that GM would've done it from the beginning, especially in the heavy duty truck applications. I've seen it done on circle cars, but those were pipes that connected to an extended thermostat housing, so the thermo still dictated the flow out. ......And I've seen at least 1 circle boat that took the water from there and dumped it overboard, it was that example that Bud said wasn't a good idea...........MP

[franky]

Connect the two ports and tap the discharge side of the tee to accept a carb jet drilled to about 0.100". Vent over the side. Keeps steam pockets from forming, better even cooling.

[Hemicbx]

Connect the two ports and tap the discharge side of the tee to accept a carb jet drilled to about 0.100". Vent over the side. Keeps steam pockets from forming, better even cooling.
I knew an old timer with a twin-turbo rat motor in a V-drive Cougar pickle fork hull. He did a similar deal. He drilled straight down (vertically) into the water jackets in two places on each head. Then he ran those lines straight to the back of the boat and discharged overboard. Claimed it would let steam pockets out and promote better water flow to all areas of the water jacket. Never seen it since. . . .

[steelcomp]

Steam pocketing is one of the "black arts" in Pro Stock engine building, and let's just say if you're not doing it right, you probably won't be competitive.
That's all I can say on that.

[Blown 472]

I take the water out of the front and the back of the head, but the water from the pump comes into the block via the drain holes, floods the block and flows up into the heads and goes out front and back, just had to match the head gaskets front to back. A very wise jet boat guru showed me this trick, haven't cracked a head since.

[396_WAYS_TO_SPIT]

yup, thats the one rio;) I was just curious because I have been seeing it around alot more these days.

[Nordicflame]

This is standard issue on Whipple kits.
Can't be too bad of an idea :cool: