Getting ready to do the swirl tank modifications.
do you use a pressure cap on the swirl cap on the swirl tabk?
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The pressure cap goes on the new "Header Tank" aka previously the overflow tank. The swirl tank is now a properly closed tank with air&fluid now leaving out of the top fitting.
wanted to keep the original two cap look.
Here are the notes I provided to Builder.
Thanks David! Looks good
Dan
David -
Are you running the same size tube from the thermostat housing to the swirl tank?
That’s an interesting fitting, it seems smaller than the stock tubing.
Nice looking tank, BTW!
JFB - Based on the detail that you have in your document (five pages) – that looks pretty expensive. Have you had good luck with your builder reading (and following) your very comprehensive instructions?
Rocky
The heads are SVO C302B so there is no thermostat housing like there is on a 351C. Each head has a -12AN coolant "out" line that connects directly to the swirl tank. BTW, two temp sensors live in this tank and there's also a sight glass, so it's easy to make sure the tank is full. A length of 1.5" tubing leaves the bottom of the swirl tank and runs all the way to a remote, by-pass thermostat at the inlet of the rad. If the thermostat is closed, coolant bypasses the rad and returns to the water pump. In the return line, there is a Stewart electric booster pump, to help the mechanical water pump pull coolant back to the engine. It's main purpose is to eliminate cavitation.
As an aside, the suction is so strong at the inlet to the electric water pump, I use it to pull coolant through the heater core. The inlet fitting is just before the remote thermostat housing, in the opposite coolant line, and the heater control valve is up there too. The heater hoses pass through the bulkhead and connect to the core with two very short hoses. This would be a good strategy for Coyote conversions, to help eliminate a bunch of heater hose related "clutter" from the front of the motor.
Also note- stock black painted steel water tanks on most Panteras were chrome or nickel plated inside and out to resist rust. Welding or brazing on such tanks will burn away the plating, then your welds will rust. Recommend you use an aluminum or SS tank as shown for such mods. I've seen everything in redneck Panteras including gallon soup cans soldered to rusted out water tanks!
So with this modification, the tall tank fills the system with the 5/8 heater hose to the water pump?
Does that take for ever to fill?
David
do you have a part number on that 8psi cap?
dan
I used a Moroso cap, Summit part # MOR-63309. It’s an 8-10 lb cap.
How full do you keep the header tank? I bought rigid acrylic pip to use has a depth gauge like an aviation fuel level tester
I initially filled my header "full" at cold. it then pee'd with several drives, leaving a cold level about 6" down. i can't recall the diameter of the tank to calculate the volume due to heat swell.
that was the amount i once calc. for coolant expansion (70 to 220f) so i set the top of header tank about 6" above top of swril so swril should stay full.
having excessive empty volume will delay building pressure as that volume of air compresses
The normal coolant level in the header tank should be at the middle of the tank. At idle, the level won’t change but it can rise and fall when driving, although only an inch or so. Even that is temporary and it will return to the mid-level. I used a sight glass on my tank, so monitoring the level was quite easy.
how do you guys have the radiator plumbed? does the top of the radiator go to the pump or from the thermostat?
On my car the top goes to the water pump. Feeding the radiator from the bottom may help push the air to the bleeder on top.
I tried it both ways on a 500 mile trip to/fm 'Vegas one year. It made absolutely no difference in how cool or hot the engine ran. And its shown both ways in various Owners Manual illustrations. But I left it as Forest said above as this may make bleeding out air easier.
Thanks
I’ve ordered a davis craig Aux water pump on a PWM temp control to go between the pump and the radiator.
i think i already have the flowkooler water pump but i ordered one anyway.
Dan, where were you going to mount the electric water pump? I was told by everyone I asked, to mount it as close to the outlet of the rad as possible, which I did. Here’s the issue: if the electric booster is putting out 35 GPM and your mechanical pump is flowing 5 GPM at idle, the suction fitting on your mechanical water pump, that is connected to your header tank, may not work. It needs to be connected to the lowest pressure point in the system and that will now be at the inlet of the electric booster pump.
A question might be asked of the inline pump maker about the likely backflow that results from 2 pumps on the same line with different flows. I always thought they would use an inline check valve? All this at ridiculously low pressure compared to industrial stuff.
connecting the pump in the front by the radiator, i’m not sure if i’ll pull from the top or the bottom yet.
i used gates hoses, i can’t imagine there would be enough pressure to collapse one.
David! you’re right, i would have to put the pump inline with the outlet, well shoot..
or tee off on the auction side of the pump to the tank.
not sure if there is enough room to mount it on the gas tank side or not, have to fabricate an online 5/8 bung.
Dan, hopefully, that booster pump is the magic pill that finally conquers your Arizona heat. Coolant flow is everything and yours is about to increase by a substantial amount. Another issue you’ll encounter is when and how fast to run the pump. Do the Davies Craig pumps block coolant flow when they are off? If so, it had better be running when the thermostat opens but on the other hand, you don’t want it running too hard against a closed thermostat.
I used a Stewart Components booster specifically because it has zero resistance to flow when it’s not running. I considered this to be a key feature of a booster pump. If it fails, you won’t need a tow truck! I really wanted to use a Meziere booster pump but it blocks flow if it isn’t running.
David, it’s a flow through and it pulses to maintain temp.
i ordered 5/8 and 3/8 aluminum tubing to run front to back and hopefully make room, i’ll have a 5/8 bung welded to a coolant tube between the pump and the radiator.
thanks for the insight, i totally never thought about it
I'm using a 13lb cap on my header tank and coolant level is about 6" down from the top. That seems to be where it works the best.
John
#3590
david
taht pump looks like a way easier install, what model did you use? how is it triggered? what controller? pics of it?
how loud is it?
also would you put the header tank suction and the heater core suction y’d together to the pump inlet?
I did, I used the heater return as my header tank suction, with heater return going to header tank. on cold crank I open heater valve to purge the heater core.
JFB
im mounting a remote booster pump near the radiator, i’m adding a bung between the pump and the radiator to go to the header tank and maybe the heater core return line
Sorry. . .
@Bell3156 posted:david
taht pump looks like a way easier install, what model did you use? how is it triggered? what controller? pics of it?
how loud is it?
Dan, my Holley Dominator activated the pump when the engine started and left it running for one minute after turning the ignition off, if the coolant temp was above 190 degrees (it never was). It always ran at full speed, so I didn't need any kind of more sophisticated control. I was told that lots of coolant flow was critical to eliminating hot spots in the cylinder heads. Speaking of heads, I also had small fittings that connected to the coolant passages in the rear face of my heads, that connected to the header tank with #4 AN hose. The model # of my pump was the E558A-BK. The pump was very quiet. I could never hear it from inside the car.
The square box to the left of the pump is the remote thermostat housing.
quite a set up!
the davies Craig suggests drilling two 1/8” holes in the stat and has its own digits trigger.
having another engine built that i’ll use the dominator and your set up.
looks good! you didn’t do the header/swirl deal?
did you hook up your heater hoses? where did the return line go, on the oem pump or to before the booster pump? or did you remove the mechanical pump?
I used a Stewart Stage 4 mechanical pump. My heater hoses were connected up front. The inlet was just before the remote thermostat housing and the outlet was just before the remote water pump. There was sufficient, unassisted flow through the core, for the heater to work fine. I ran the heater hoses through bulkhead fittings on the front bulkhead.
so where was the header tank connected?
pretty intricate design
Nice work, David. Very impressive.