[opeliac]

I read through past threads, and have a few questions...I'm building a 482" with a IA2 dry deck block and edelbrock heads...

I am going to use a remote meziere pump with two outlets...My plan is to split one outlet and feed the front of the block, split the other and feed the front of the heads, and then return all four back to the radiator...Does anyone see an issue with this?

I ask because it seems that most come out of the rear of the block, then route back in at the rear of the heads, then out of the front of the heads and back to the radiator...



Any ideas/info is appreciated.

[taff2]

Yes, the rear two cylinders/chambers 7 & 8 will have the hottest of the coolant flow as it takes the heat from the front 6 cylinders/heads, these rear 2 cylinders will run very hot. Hot enough on my previous turbo combo to burn the paint on the block . A better way is to feed the coolant into the front of the heads with one pump outlet, but then feed coolant from the other pump outlet into the rear of the block - this will average out all the cylinder/chamber temperatures.
This is just what I'm doing with my current combo, except that I have drilled/tapped the SBC electric pump for two extra outlets , and then feed two lines to the rear of the heads and two lines to the front of the block - all terminating in a Moroso thermostat housing (minus the 'stat) before returning to the radiator.

[opeliac]

Originally Posted by taff2

Yes, the rear two cylinders/chambers 7 & 8 will have the hottest of the coolant flow as it takes the heat from the front 6 cylinders/heads, these rear 2 cylinders will run very hot. Hot enough on my previous turbo combo to burn the paint on the block . A better way is to feed the coolant into the front of the heads with one pump outlet, but then feed coolant from the other pump outlet into the rear of the block - this will average out all the cylinder/chamber temperatures.
This is just what I'm doing with my current combo, except that I have drilled/tapped the SBC electric pump for two extra outlets , and then feed two lines to the rear of the heads and two lines to the front of the block - all terminating in a Moroso thermostat housing (minus the 'stat) before returning to the radiator.

What about feeding the front, and rear of the block, and then return it out through the freeze plugs? At the point, you could actually put a temp sender at each freeze plug outlet and restrict the cooler ones until you even out the temps...

The heads will be on their own...

[GTOGEORGE]

A long time ago when u was running gas I drilled and tapped my electric water pump for two hoses and ran them to the back of the heads to get cooler water to the heads (water not going through the block first), didn’t run it long engine to see if it helped or not.
I had to run a hose from the back of the block under the intake to the water crossover in the intake. So basically I was feed the front of the block and the rear of the heads at the same time.

GTO George

[taff2]

It will be a fair amount of work to make outlet fittings to fit in the freeze plug holes, I just drilled and tapped the side of the block for 1/2" NPT fittings.

[opeliac]

Originally Posted by taff2

It will be a fair amount of work to make outlet fittings to fit in the freeze plug holes, I just drilled and tapped the side of the block for 1/2" NPT fittings.

Shouldnt be hard to drill and tap the freeze plugs.

[taff2]

You're not going to get much thread engagement in a 1/16" thick core plug, and then hanging an AN10 hose and fitting off it...

[opeliac]

Originally Posted by taff2

You're not going to get much thread engagement in a 1/16" thick core plug, and then hanging an AN10 hose and fitting off it...

IA2 has screw in freeze plugs

[RAIV-Z]

I run 2 lines into the fron of the block, cross-over in the back and out the front of the heads to the radiator.

[opeliac]

Originally Posted by RAIV-Z

I run 2 lines into the fron of the block, cross-over in the back and out the front of the heads to the radiator.

That seems to be the way that most are doing it...Any idea why?

Are you guys wanting the warmer water in the heads, as opposed to cooler straight from the radiator?

[GTOGEORGE]

Originally Posted by RAIV-Z

I run 2 lines into the fron of the block, cross-over in the back and out the front of the heads to the radiator.

Thats the way I run my lines but If you come off the water pump and go straight to the back of the heads its cooler water, then bring the lines from the back of the block forward to the intake crossover it should be better.


GTO George

[Tom Vaught]

WHY! I did some similar testing on a back in the 2006 timeframe on a Supercharged engine run on a very accurate dyno cell with very good instrumentation per cylinder.

The engine was plumbed somewhat like a 1965 GTO engine with a heater nipple located on the rear of the passenger head. The people in charge wanted even cylinder temps across all 8 cylinders. They were not willing to go in and change water passage size holes in the block or the heads.

This is what we documented:

1) The drivers side rear of the engine was hotter vs the front of the engine. Dead flow area just like a Pontiac engine (A combination of TRAPPED AIR at that rear portion of the head. Higher combustion and water temps at that location.

2) The passenger side rear of the head was cooler vs the Driver's side head at the rear.
Reasons for that were the rear cylinder saw lots of flow passing by that location.
The front of the passenger head was running hotter vs the drivers side head due to the heater hose and heater inlet pick-up point robbing flow from the rest of the passenger head.

3) So what did I do:

a) I moved the water inlet location for the heater to a location at the front of the engine manifold cross-over. (like a 1962-64 Pontiac Heater hose pick-up point).

b) I added two "Trapped Air" bleed hoses at the rear of the cylinder heads (1/4"ID hose)
and connected these to the water crossover manifold (before the thermostat). I wanted to remove the air primarily, not change the engine basic cooling strategy designed by the Coolant Engineers. Again this was a 50 vehicle test program and not a modification to the cooling strategy for the engine fleet so everyone signed off on the modifications.

We tested the engine again for about 400 hours of dyno time.

The cylinder to cylinder combustion temps were much closer together, the the power per cylinder actually improved at the drivers side rear location and the passenger side front cylinders due to more even cooling and more even timing control for all cylinders.

So the reason why people are doing this is partially because others are doing it.
But a few are doing it (like Langer) to make the engine more efficient for each cylinder.

Most do not have the heater hose hooked up but they would still have the trapped air issue with both cylinder heads (without doing the mods and adding the hoses to get rid of the trapped air at the rear of the heads.

The Pontiac mod is removing air from both the rear of the heads and the rear of the block. A good modification.

One piece of data is worth a thousand opinions. Jim Clarke.

Tom V.

[GTOGEORGE]

OR......REAL experience on a Race car "doing it" is FAR more accurate then paper Data! LOL!


GTO George

[RAIV-Z]

Originally Posted by opeliac

That seems to be the way that most are doing it...Any idea why?

Are you guys wanting the warmer water in the heads, as opposed to cooler straight from the radiator?

At the time, it was the best way to run the lines. The engine runs cool, so no plans to try running the water into the heads first.

[opeliac]

Originally Posted by Tom Vaught

WHY! I did some similar testing on a back in the 2006 timeframe on a Supercharged engine run on a very accurate dyno cell with very good instrumentation per cylinder.

The engine was plumbed somewhat like a 1965 GTO engine with a heater nipple located on the rear of the passenger head. The people in charge wanted even cylinder temps across all 8 cylinders. They were not willing to go in and change water passage size holes in the block or the heads.

This is what we documented:

1) The drivers side rear of the engine was hotter vs the front of the engine. Dead flow area just like a Pontiac engine (A combination of TRAPPED AIR at that rear portion of the head. Higher combustion and water temps at that location.

2) The passenger side rear of the head was cooler vs the Driver's side head at the rear.
Reasons for that were the rear cylinder saw lots of flow passing by that location.
The front of the passenger head was running hotter vs the drivers side head due to the heater hose and heater inlet pick-up point robbing flow from the rest of the passenger head.

3) So what did I do:

a) I moved the water inlet location for the heater to a location at the front of the engine manifold cross-over. (like a 1962-64 Pontiac Heater hose pick-up point).

b) I added two "Trapped Air" bleed hoses at the rear of the cylinder heads (1/4"ID hose)
and connected these to the water crossover manifold (before the thermostat). I wanted to remove the air primarily, not change the engine basic cooling strategy designed by the Coolant Engineers. Again this was a 50 vehicle test program and not a modification to the cooling strategy for the engine fleet so everyone signed off on the modifications.

We tested the engine again for about 400 hours of dyno time.

The cylinder to cylinder combustion temps were much closer together, the the power per cylinder actually improved at the drivers side rear location and the passenger side front cylinders due to more even cooling and more even timing control for all cylinders.

So the reason why people are doing this is partially because others are doing it.
But a few are doing it (like Langer) to make the engine more efficient for each cylinder.

Most do not have the heater hose hooked up but they would still have the trapped air issue with both cylinder heads (without doing the mods and adding the hoses to get rid of the trapped air at the rear of the heads.

The Pontiac mod is removing air from both the rear of the heads and the rear of the block. A good modification.

One piece of data is worth a thousand opinions. Jim Clarke.

Tom V.

Were those tests done on a dry deck combo?

[Tom Vaught]

We did a lot of different configurations, wet deck, dry deck, separate pumps for each, same dual outlet pump Meziere feeding each system separately.

Dry deck was tested but for the application and the different climates the vehicles were tested in we stayed with a normal head gasket flow for the final testing.

Despite what one individual (who never did the job thinks), none of these were paper studies. Paper studies did not win the 24 hours of Le Mans. Actual vehicle testing and hard work did. Mr Paper Study, we ran 40 mph faster than your Best quarter mile MPH, every lap for 24 hours, with a 6 cylinder engine. LOL!

Tom V.

I answered the WHY question. The HOW question can be several different ways.







Tom V.

[LMSRACER]

RAIV-Z is running Ram Air V Heads that do not have siamesed Exhaust Ports. That makes a big difference and may be why he's not having any issues. You, on the other hand are running Heads that have siamesed Exhaust Ports.

IMO, Plumb one outlet from your Pump to the Front and Center (which you will add) Coolant Passages in each Head. Then take the rear Passage in the Head and plumb that Passage to the opposite bank at the rear of the Block. This will give you Reverse Flow Cooling.

The only reason for crossing the Coolant Lines in the rear of the Block/Head Area is ease of plumbing.

The Center Coolant Passage/Passages is/are most effective when added below the siamesed Exhaust Ports.

This pertains to Dry Decked configurations.......

NOTE:
To take advantage of the Dry Deck Arrangement, all of the Coolant Passages in the Deck Surface of the Edelbrock Head should be welded shut/closed.

Be careful who you chose to weld the Deck Surfaces as you may find that the Surface may be softened to the point that the O-Rings/Fire Rings will create depressions in the Deck Surfaces or the Head Studs will not be able to maintain their Torque Setting.

Once again, just My Opinion.

Laurence Snyder

[opeliac]

[QUOTE=Tom Vaught;6247651]We did a lot of different configurations, wet deck, dry deck, separate pumps for each, same dual outlet pump Meziere feeding each system separately.

Dry deck was tested but for the application and the different climates the vehicles were tested in we stayed with a normal head gasket flow for the final testing.

Despite what one individual (who never did the job thinks), none of these were paper studies. Paper studies did not win the 24 hours of Le Mans. Actual vehicle testing and hard work did. Mr Paper Study, we ran 40 mph faster than your Best quarter mile MPH, every lap for 24 hours, with a 6 cylinder engine. LOL!

Tom V.


Obviously you are way sharper on this than i'm ever going to be, so i'll just ask you what the negatives would be if I run a dry deck combo, feed in the front of the block, AND heads, and return all 4 from the rear back to the radiator...

I have read your post multiple times, and apparently missed the reason why this wont work...You can call me dumb...

[Tom Vaught]

Describe the pump and the plumbing you are going to use.
Describe the Mods to the heads as Larry mentioned.
Then we can go from there. The center of the head feed for additional cooling has been proven by Langer and others.

Tom V.

[opeliac]

Originally Posted by Tom Vaught

Describe the pump and the plumbing you are going to use.
Describe the Mods to the heads as Larry mentioned.
Then we can go from there. The center of the head feed for additional cooling has been proven by Langer and others.

Tom V.

Heads will be plugged and welded..

I have the dual outlet Meziere 55gpm pump...I plan to split one outlet and enter the front of the block, split the other outlet and enter the front of the heads...I'm not sure on plumbing into the center of the heads yet, but i'm open to it...

I am also thinking about entering the block in the front AND the back, and exiting it out of the freeze plugs then returning to the radiator. Or, enter in the freeze plugs, and out of the front and the back...

If I am over thinking this, its ok to tell me that...Its in a chassis car, so the plumbing isnt much of an issue.