Keeping my upgraded motor cool

[Milwaukee Midget]

Like I said in my previous statements the temp rose very fast in the last mile of the run. 

 

Sustained high speed operation can lead to coolant cavitation.

If it's a stock style pump, how fast are you spinning it?

I'd be tempted to make sure the system you have in place is working 100% - there may not actually be a problem that simply changing the pulley to slow the pump down won't fix.

[Paul P]

Like I said in my previous statements the temp rose very fast in the last mile of the run. 

 

Sustained high speed operation can lead to coolant cavitation.

If it's a stock style pump, how fast are you spinning it?

I'd be tempted to make sure the system you have in place is working 100% - there may not actually be a problem that simply changing the pulley to slow the pump down won't fix.

It's a billet pump specifically designed to run at high speed.  The fastest I could spin it was 7100 rpm's but my target is 8000 rpm's.  I have changed gears so 8000 rpm's will happen next time.

[Paul P]

Well Evans Coolant is out.  Thanks Milwaukee.

Hey TheBaron can you give any details of the spray bars (manufacturer info) and what type of pump are you using?  Any details would be appreciated.  My air intake is under the hood so the motor would be eating the water too.  Not sure what effect, if any, that would have on performance.

I did leave out one detail, I am running an air/water intercooler for the turbo.  It uses 3 bags of ice per run.  Tank holds a total of 15 gallons and the water in the tank after a run is lukewarm. 

  Can you put more ice in the tank? We put 10 bags, 100 lbs in our tank but its about 38 gal and a 12 x12 internal size intercooler. 24 lbs boost, no radiator about 24 gal water tank over 2000 hp and no cooling problems.

 How much boost do you have? Bigger intercooler and tank should help lower air temps = lower engine temps.

   JL222

Yes I could add more ice to the tank for the intercooler.  It's 15 gallons total and I could drain more water and add more ice per run.  I have been running up to 25 lbs of boost but I want to increase it to 40 lbs. 

[1leg]

We have had success using our 55gpm electric pump to feed the stock mechanical drive pump. This helps to prevent cavitation I high pump speeds.
You would plumb the pump in line on the lower radiator hose with the pump outlet going toward the inlet of the stock pump.
I also suggest running the stock size hose which is normally about 1.75”.

This also allows you to run the electric pump after running the engine to continue to cool the engine.
The 1 drawback is you need to make sure the electric pump is running whenever you are running the engine.
The mechanical pump will not be able to pull coolant through the electric pump.

Let me know if you need any help.

[Paul P]

We have had success using our 55gpm electric pump to feed the stock mechanical drive pump. This helps to prevent cavitation I high pump speeds.
You would plumb the pump in line on the lower radiator hose with the pump outlet going toward the inlet of the stock pump.
I also suggest running the stock size hose which is normally about 1.75”.

This also allows you to run the electric pump after running the engine to continue to cool the engine.
The 1 drawback is you need to make sure the electric pump is running whenever you are running the engine.
The mechanical pump will not be able to pull coolant through the electric pump.

Let me know if you need any help.

After much thought and a few calls to the tech guys for SCTA I think my best approach is to build a 10-15 gallon external tank that will feed the mechanical pump with an electric pump (like you described) then run the output from the engine through the radiator and the outlet of the radiator back into the external tank.  I will mount a couple of good puller fans on the radiator for cooling between runs and I have verified with the mechanical pump builder that the electric pump will be able to pump past the mechanical pump fairly easy when the motor is not running.  The biggest challenge I see is accounting for the pressure in the cooling system with all the hoses running from the back of the car to the front and the possibility of a high pressure situation such as a blown head gasket.  I don't want the tank blowing hot water inside the car if a blown head gasket causes the pressure to spike. 

What's your opinion on the size of the external tank?  I am running a small (172 ci) F class motor and I am sure the regular cooling system doesn't hold more than 3-4 gallons.  I am thinking a 10-15 gallon tank will be completely circulated about twice during the 2 minutes of actual run time.  That should keep things under control I think.  What do you think?

[Stainless1]

Do you run a thermostat?
I'm sure you run a pressure cap... one should also be on your tank.... that should keep the water confined to the hoses... but you can use stainless tubing to run through the cockpit so water hot water can't spray on you if there is a mishap
You may want to look at putting a radiator in a water tank... search the site for info on that.

[Paul P]

Do you run a thermostat?
I'm sure you run a pressure cap... one should also be on your tank.... that should keep the water confined to the hoses... but you can use stainless tubing to run through the cockpit so water hot water can't spray on you if there is a mishap
You may want to look at putting a radiator in a water tank... search the site for info on that.

No thermostat.  I will run a 20 lb. cap. 

[John Burk]

Paul , thermostats create back pressure that raises the boiling point in the engine quite a bit .

[Milwaukee Midget]

It's a billet pump specifically designed to run at high speed.  The fastest I could spin it was 7100 rpm's but my target is 8000 rpm's.  I have changed gears so 8000 rpm's will happen next time.

This is my point - you may actually be spinning the water pump too fast for an LSR application.

By slowing the flow down, you may actually be able to pull more heat out of the engine.

If the coolant is moving too fast through the block and radiator, you may not be able to effectively release the heat through the radiator, which allows warmer water into the engine and the temp creeps up.

We wound using pulleys which slowed our water pump down to about 60% of what the stock pump was turning, and and I don't think we hit 200 degrees.

[Dynoroom]

Chris is right. Not all but most automotive water pumps are designed turn ~4,500 rpm max. My water pump is a racing pump but I run it at 60% of crank speed. YMMV

[Interested Observer]

It's a billet pump specifically designed to run at high speed.

Patent nonsense.  Unless you have a valid pump delivery curve hopefully operating under the required conditions, you don’t know what it is doing.

By slowing the flow down, you may actually be able to pull more heat out of the engine.

If the coolant is moving too fast through the block and radiator, you may not be able to effectively release the heat through the radiator, which allows warmer water into the engine and the temp creeps up.

Unfortunately, this too is an erroneous notion, however seductive it is.   It will not stand up to an actual heat transfer analysis. 

Slowing the pump down may be advantageous due to possibly avoiding cavitation and consuming less horsepower, but not because the coolant goes through the radiator too fast.

[fordboy628]

It's a billet pump specifically designed to run at high speed.  The fastest I could spin it was 7100 rpm's but my target is 8000 rpm's.  I have changed gears so 8000 rpm's will happen next time.

This is my point - you may actually be spinning the water pump too fast for an LSR application.

By slowing the flow down, you may actually be able to pull more heat out of the engine.

If the coolant is moving too fast through the block and radiator, you may not be able to effectively release the heat through the radiator, which allows warmer water into the engine and the temp creeps up.

We wound using pulleys which slowed our water pump down to about 60% of what the stock pump was turning, and and I don't think we hit 200 degrees.

Chris is right. Not all but most automotive water pumps are designed turn ~4,500 rpm max. My water pump is a racing pump but I run it at 60% of crank speed. YMMV

Paul,

Some things to consider:

A/   Oil temp in the pan is fine.   Wet Sump?    Oil manufacturer can suggest the "optimum" temp range for their product.    Sustained operation @ very elevated temps is going to require use of a synthetic based lubricant to retain film strength at those high temps.   Loss of lubricant film or lubricant "breakdown" will kill your bottom end in short order with a turbo.   Depending on high temp film strength, very hot oil might gain extra bhp.  I typically use 220/235 degrees F.

2/   Some sort of "restrictor" should be installed in the engine coolant (water) outlet.   This will raise the pressure in the coolant passages and can prevent localized "boiling", common with a "free flow" system.    Run as high a pressure cap as you can, as this also adds protection.

d/   Keeping coolant temp low, within reason, can allow extra boost or timing, thereby improving bhp output.   Realize that this is a "balancing act".    Your goal should be to have a temp under 212 F (less would be better) at the end of your run.

z/   Billet pump for high speed?!?*?     NO SUCH ANIMAL.   Check out the pump drives on Cup engines . . .  notice that the pumps run @ approx 50% crank speed.   That's not a happy accident.   Engineer your setup for 4000/4500 pump shaft rpm max.    There are numerous pulley ratios available for v-belts, poly v-belts, and gilmer drives.    Do some research.

 
Fordboy

[Paul P]

Paul , thermostats create back pressure that raises the boiling point in the engine quite a bit .

The main issue I see with using a thermostat is the delay in opening.  Can it react fast enough?

[Paul P]

It's a billet pump specifically designed to run at high speed.  The fastest I could spin it was 7100 rpm's but my target is 8000 rpm's.  I have changed gears so 8000 rpm's will happen next time.

This is my point - you may actually be spinning the water pump too fast for an LSR application.

By slowing the flow down, you may actually be able to pull more heat out of the engine.

If the coolant is moving too fast through the block and radiator, you may not be able to effectively release the heat through the radiator, which allows warmer water into the engine and the temp creeps up.

We wound using pulleys which slowed our water pump down to about 60% of what the stock pump was turning, and and I don't think we hit 200 degrees.

Chris is right. Not all but most automotive water pumps are designed turn ~4,500 rpm max. My water pump is a racing pump but I run it at 60% of crank speed. YMMV

Paul,

Some things to consider:

A/   Oil temp in the pan is fine.   Wet Sump?    Oil manufacturer can suggest the "optimum" temp range for their product.    Sustained operation @ very elevated temps is going to require use of a synthetic based lubricant to retain film strength at those high temps.   Loss of lubricant film or lubricant "breakdown" will kill your bottom end in short order with a turbo.   Depending on high temp film strength, very hot oil might gain extra bhp.  I typically use 220/235 degrees F.

2/   Some sort of "restrictor" should be installed in the engine coolant (water) outlet.   This will raise the pressure in the coolant passages and can prevent localized "boiling", common with a "free flow" system.    Run as high a pressure cap as you can, as this also adds protection.

d/   Keeping coolant temp low, within reason, can allow extra boost or timing, thereby improving bhp output.   Realize that this is a "balancing act".    Your goal should be to have a temp under 212 F (less would be better) at the end of your run.

z/   Billet pump for high speed?!?*?     NO SUCH ANIMAL.   Check out the pump drives on Cup engines . . .  notice that the pumps run @ approx 50% crank speed.   That's not a happy accident.   Engineer your setup for 4000/4500 pump shaft rpm max.    There are numerous pulley ratios available for v-belts, poly v-belts, and gilmer drives.    Do some research.

 
Fordboy

I seem to have created a monster from my statement that the pump is designed to run at high rpm.  I should have added the pump AND pulley combination are designed to run at high rpm.  It's an Esslinger pump and pulley and I am sure they know about high rpm applications.

[Stainless1]

Personal opinion... Run a thermostat... especially if you add a water tank
We ran without one for a lot of years, data always showed the water was in the 220 range at the end of a run... we had a small radiator with a NACA duct, data showed it removed about 3-5 degrees, we needed the room so we took it out.  This is an enclosed car, 5 gallon water tank, both 1 liter and 65 inch, approximately 250 HP (not dyno verified) N2O motors  that were warmed to 100 degree tank water temp and hotter than that oil temp before a run. 
Changed to a 90 inch motor after the 65 inch motor failed (understatement) and left the stock 180* thermostat in.  Warm up time reduced to thermostat opening, about 5 minutes or so with oil pan too hot to leave your hand on it, then allowing the motor to heat soak from there.  Can see thermostat opening and restricting on the data, water 180 to 190 entire run. HP close to the same, ran about 1 MPH slower on gas than the 65 did on N20. 
So yes I recommend running a thermostat to help control the heat
YMMV