Yellow Bullet Forums banner

1 - 19 of 19 Posts

·
Registered
Joined
·
3,804 Posts
Discussion Starter #1
About to fire up my engine , 588 BBC aluminum heads , Bracket car . I have a few cooling system questions :
First what type of coolant should I run , Distilled water or just tap water .I know NO ant-freeze . I plan on running some type of water wetter as well.I was also reading that some guys use bottled drinking water as well.
Second question is my radiator is lower than the water neck so that's where my fill is gonna be(water neck) and obviously where my one of my caps is gonna be is gonna be .Radiator called for 22-24 lb cap .What do I do about the radiator cap on the actual radiator . I'm thinking it's gonna be less lbs .Or do I just weld up a screw on cap ?
I'm running the biggest Moroso restrictor plate as far as holes go in the water neck as well.
As far as overflow I just have a Jaz overflow tank coming off the water neck .
Thanks in advance
 

·
Registered
Joined
·
2,462 Posts
I use tap and water wetter.
That’s a lot of pressure for a cap.
Never seen one for cars that high.
Get a Lisle radiator fill kit.
Great tool. 30 bucks on internet stores.
Keeps fill high.
 

·
Registered
Joined
·
711 Posts
Ditch the filler neck on the intake and fill at the radiator. It will help you get the air out of the system easier.
16lbs radaitor cap is all you need.
If your running an electric water pump remove the restrictor is will help you get more water flow and help to cool down between round quicker.
Use a recovery style catch can to manage air int he system.
 

·
Registered
Joined
·
12,991 Posts
I used distilled water and NAPA Kool additive.

Getting close...Sounds good buddy.
 

·
Registered
Joined
·
150 Posts
Ditch the filler neck on the intake and fill at the radiator. It will help you get the air out of the system easier.
16lbs radaitor cap is all you need.
If your running an electric water pump remove the restrictor is will help you get more water flow and help to cool down between round quicker.
Use a recovery style catch can to manage air int he system.
With radiator lower than neck, I'd keep the neck. Always better to purge air from highest point in the cooling system.

16lb cap more than enough pressure to allow system to work correctly.
 

·
Registered
Joined
·
3,970 Posts
Jack the front end up until the cap on radiator is highest point and fill and let air out there. You can drop the front end fast and burp some more air out. You don't really want 2 caps and have to have 2 overflow tanks. Usually a 10# cap is enough for strictly drag racing. Use filtered water from WalMart. Use a wetter wetter that does not have cellulose in it, it will turn to brown mud. Use a recovery tank and not an overflow tank.
 

·
Registered
Joined
·
16,315 Posts
Here's some info to think about. I have a pressure sensor on my engine at the intake manifold so it basically measures the coolant system pressure before it enters the radiator. When the engine is hot and running at low rpm, the pressure reading will be close to the pressure on the radiator cap - 16lbs.

I have a mechanical pump so it pumps more flow at higher pressure with higher engine rpms. Going down the track I see pressures up to 25-30lbs. There is a huge pressure drop at high flow rates between the intake water neck location and the radiator cap side of the radiator. Because of this, the pressure at the cap is still "normal" so the system is not pushing fluid out thru the radiator overflow.

My point is simple. The measured system pressure will vary depending on flow thru the system. An electric pump this will be less of a variation but a mechanical pump it can be quite significant. Regardless, the cap pressure setting at the normal location on the radiator (inlet side of pump) will be the most predictable and have the least amount of variation.
 

·
T/S 368E
Joined
·
26,104 Posts
.

You can't use tap water if you have nasty ass well water, trust me I learned the hard way :(

I know it's being argued now a days, but I used distilled water 20+ years with zero issues and no additives.
I also use a 28 lb cap IIRC. My guy took the plate off trying to be sneaky I guess??
I always use a higher or equal cap at the radiator than the intake.

I want the biggest volume you can fit for a bracket car, the more water the better.
Also the best electric pump you can afford, again, the more volume of water moving the better.


.
 

·
Registered
Joined
·
150 Posts
Ok 16 lbs on water neck ,What about the cap on the radiator ?
I'd run 16lb on neck with overflow to tank and solid cap on radiator with no overflow outlet. Based on your description, this would make system perform well and easiest to deal with (air, etc.). BTW - airlift is excellent for any cooling system. Surely, the simplest/fastest way to get a system filled correctly.
 

·
Registered
Joined
·
14,431 Posts
OP, read the Wetter Water bottle or similar product bottle. Some of those type products say DO NOT use with distilled water.
 
1 - 19 of 19 Posts
Top