Water tank construction

[Dynoroom]

Generally, when I see pressure come up in the cooling system, shortly after start up and when load is applied, that is a sure sign that the head bolts/studs are inelastic.  The heads will start to grow quickly, and the gas leakage past the fire ring stops quickly....but cooling system pressure takes a jump when read directly.  Usually, I see the head bolts/studs overtorqued.  This can be really ugly when running aluminum heads.

Regards, JimL

Again, this is not totally true. Sorry Jim but the extream case you mention is not the issue here. If you look at the head gaskets you'll see different size coolant passages. This is what helps make pressure in the block. When you put a pressure tap in the block water jacket you'll see what I mean....

Back on topic, water tanks are your friend at Bonneville.

[John Burk]

A few thoughts .

A hose from the top of the water tank to the bottom of an over-flow tank with the pressure cap on the OFT would allow the water tank to be topped off .

A problem with a circuitous path tank is the bubbles can't get out .

A tank can't bulge if the sides arn't flat . A cross-section is like CCCCD .

Without enough outlet back pressure the boiling around the exhaust ports has all the symptoms of an overheated engine . Top fuel engines need no cooling because of the fuel blown out the exhaust port during the overlap .

[McRat]

Luckily, with a pickup, we can put the tank in the bed, and have no water lines in the cab.  But in a car, it would be very bad to have steam or boiling water intrusion.  The driver might have to change his name to Stew.

My thoughts were to have pressurized water move very, very rapidly through the block and heads to stop hot spots by way of removing heat as fast as possible, but I have zero experience in this area.  Seems this is not the right path.

Our pistons overheated last year, yet water temps never went past 210F on exit in a 15psi pressurized system with radiator.   So 210F water might not work me, and was looking for 160deg water to give the water more punch.  Probably using the factory cooling system, designed for 310HP, wasn't too clever when running 3 times the power.

Well, I'll build the tank to hold pressure, and put extra fitting plugs in for changing it's configuration.

[Rex Schimmer]

First a couple of things regarding water. It is compressable, if you look at the great web site that Doc Goggles provided go to the "Bulk Modulus" of water and it gives a pretty good example of how much force it takes to compress water (and also other fluids). Every thing is compressable, even steel, it just takes more force. Second pressure in a fluid system is developed when there is resistance to flow, which is why Dynoroom sees pressure without having any water temperature. Third: Air in the water: Being concerned that you need to be able to have the air in the water come out in the water tank, if you have the system pressurized to above 15 psi is a mott point, once the system is at 15 psi any air that is desolved in the water is trapped. Because of the very low viscosity of water it does not hold air in solution well so this is probably not worth even worrying about. If you are concerned with the fact that you may have air pockets in the engine then you don't have a big enough water pump. Yes the expansion of the water due to heat makes pressure, but a properly designed cooling system will use a pump that can develop 30 to 40 psi of pressure when it tries to pump the proper amount of water through the engine (10 gallons per minute per 100 hp is a good rule to sizing the pump). So now the pumps inlet sees the pressure in the tank and then that pressure is added to the pressure developed by the pump forcing the water thru the restrictions of the engines cooling system. So the engine looks like a big orifice to the water pump with the pressure on one side being the "orifice" resistance to water flow and the pressure on the other side is the pressure in the water tank which also happens to be the pumps inlet pressure. You cannot have to big of a water pump, and you cannot pump the water to fast thur the engine, all of the BS that is out there about if you pump it to fast it does not have enought time to adsorb the heat is just that! pure and simple BS!!! A water pump that is pumping 100 gpm at 40 psi and is only 50% efficient only requires 5 horse power to turn, which is a good reason to avoid electric water pumps, they will not make this type of pressure.

Regarding the 30x16x12 rectangular tank that Krusty wantst to build, your material selection is good but you will, you must! internally brace the large 30x16 sides of the tank or it WILL deform to a nice somewhat round shape. Using internal stiffeners or welding a series of alum rods in various places from one side to the other will work, and the more the better. I would also to some on the 12 inch sides just to be safe.

Rex

[McRat]

Hmmm...  That seems to make sense.

Guess I go with plan "A", and make sure I have >100g/min capabilities and can develop 40psi "post-pump, pre-block".

[John Burk]

We talked about this in the past but what methods does anybody use with copper head gaskets to seal around water holes ?

[Dynoroom]

Hmmm...  That seems to make sense.

Guess I go with plan "A", and make sure I have >100g/min capabilities and can develop 40psi "post-pump, pre-block".

Note: When using a water tank like we do at the salt or the lakes the coolant gpm from a stock type pump is not a major issue (i.e. chevy at 40 gpm example). If running a closed system in an endurance application then Rex's 10 gpm per 100 hp is a very good baseline, it worked for those Offy's huh Rex.  

[Dynoroom]

We talked about this in the past but what methods does anybody use with copper head gaskets to seal around water holes ?

Wwhen I'm forced to use copper I use orange hi-temp silicone and sewing thread on both sides of the gasket around the coolant passages.

John if your running a big block (I think you are?) there's a company in Lancaster, ca. called SCE that has gaskets with silk screened silicone around the coolant passages.

[jl222]

We talked about this in the past but what methods does anybody use with copper head gaskets to seal around water holes ?

  I just use silicone, a little dab and thin smear around hole on block then gasket.

   JL222

[Dynoroom]

We talked about this in the past but what methods does anybody use with copper head gaskets to seal around water holes ?

  I just use silicone, a little dab and thin smear around hole on block then gasket.

   JL222

What type water pump are you running John? Most copper gaskets leak if you use a mechanical pump that builds block water pressure....

[jl222]

We talked about this in the past but what methods does anybody use with copper head gaskets to seal around water holes ?

  I just use silicone, a little dab and thin smear around hole on block then gasket.

   JL222

What type water pump are you running John? Most copper gaskets leak if you use a mechanical pump that builds block water pressure....

 I just run a small jabsco electric water pump I forget the gallons per min but about 8 or less. We have about a 20 gal tank and unpressurized but have a gatevalve in the return that we vary when warming up, then leave about 3/4 closed
when running. Never gets above 180 on runs

              JL222

  Good info on pressurized systems I better not do it. You wouldn't believe the trouble we had to make this block flow water and we had to punch our own holes in the gaskets after special ordering them for water.

[The wonderful One]

May I offer something here? I just had a fuel tank built by Kenny Upton here in So Cal. (Disney Land area)14ga. SS - AN/SS fittings and just a work of art. Complicated 16 gallon tank. $300.00. I will have him do the water tank in my car also and it will be much less. I will share his information if you wish and will post a picture in this week. The Wonderful One