3 gallons

[dvx216]

5.7 v8 raw water cooled took 3 gallons using the method of pour anti-freeze into intake manifold after removing the thermostat.Roughly 2 1/3 gal. in the block and the rest poured into the exhaust manifolds until it comes out the outdrive.
I'm sure someone is going to ask so there it is. If someone gets a different result so be it but that is what I did today.
It's up to you what color and type of anti-freeze you use but that is what I came up with.I personally pay the extra
money for Quick Silver -100 degree but that's just me.

 

[Strecker25]

5.7 v8 raw water cooled took 3 gallons using the method of pour anti-freeze into intake manifold after removing the thermostat.Roughly 2 1/3 gal. in the block and the rest poured into the exhaust manifolds until it comes out the outdrive.
I'm sure someone is going to ask so there it is. If someone gets a different result so be it but that is what I did today.
It's up to you what color and type of anti-freeze you use but that is what I came up with.I personally pay the extra
money for Quick Silver -100 degree but that's just me.

Sounds about right. i was about 4gals per motor on our 350's but we have the 3" riser extensions, and I filled the intake hose/CF/PS cooler until the pink came out the drive inlets.

 

[dvx216]

Just an FYI because someone always asks

 

[Strecker25]

Just an FYI because someone always asks

yep, good info!

 

[Bt Doctur]

I have had it go between 2 gallons and 2 -3/4 gallons just in the motor.Could be a design change in the block casting method.

 

[LiquidWrench]

Makes me glad all I had to do last year was drain my risers, PS cooler, and heat exchangers. This year thanks to a move in a couple weeks I won't even have to think about winterizing ever again.