Thread: what is the best coolant for the V8??

Originally Posted by Hardchina

Mate if it never went above 1/3 youre probably missing a thermostat. I'd check, just in case

I fitted a brand new one myself when I refitted the heads, has no coolant at the moment as I am about to flush it & then refill it with a decent coolant to try to keep the old girl alive.

I trust you put in an 88C .

I reckon even an 82C might fall under 80C on a very cold day and send the injection into cold start mode.

Regard sPhilip A

I use Nulon Ultra Cool mixed with demineralized water. It is a rust, scale inhibitor, not an anti-freeze, anti-boil coolant. It provides maximum thermal efficiency because it contains no glycol. Costs about $9 for 500ml which treats 10 litres of water.

Originally Posted by PhilipA

I trust you put in an 88C .

I reckon even an 82C might fall under 80C on a very cold day and send the injection into cold start mode.

Regard sPhilip A

Was fitted with whatever the "recommended" thermostat is......... will have to pull it out & have a gander.

Originally Posted by Traco

I use Nulon Ultra Cool mixed with demineralized water. It is a rust, scale inhibitor, not an anti-freeze, anti-boil coolant. It provides maximum thermal efficiency because it contains no glycol. Costs about $9 for 500ml which treats 10 litres of water.

This sounds exactly like what I'm after, any idea of how much water is in the system? my service book is still pack away in the container somewhere

Originally Posted by PAT303

Good point,if the thermostat is missing the coolant bypasses the block and the engine will boil.I get my rad cleaned,filled and pressure tested for $110. Pat

The coolant cant bypass the block as the t/stat position is not a 3 way join the t/stat simply opens and shuts depending on the temperature allowing more or less water to flow through the block. There is an enourmous anount of debate on whether removing or leaving it in is better or worse, my thoughts are the design engineers have better brains than me so I leave it in. BUT we can change one to suit the enviornment we live and drive in.

Originally Posted by PhilipA

I trust you put in an 88C .

I reckon even an 82C might fall under 80C on a very cold day and send the injection into cold start mode.

Regard sPhilip A

as a point of reference, i fitted an 82C thermostat into my 3.5V8 which has been megasquirted, therefore i can plug the laptop in and log the data coming from the sensors when i drive

i found on the freeway the temperature dropped to 77C on a 16C day, i took it offroad and in low range the whole time, the highest it got was 83C but that was for very brief periods, most of the time it was 80-81C

and driving around town, it was at a constant 79C

Originally Posted by blitz

The coolant cant bypass the block as the t/stat position is not a 3 way join the t/stat simply opens and shuts depending on the temperature allowing more or less water to flow through the block. There is an enourmous anount of debate on whether removing or leaving it in is better or worse, my thoughts are the design engineers have better brains than me so I leave it in. BUT we can change one to suit the enviornment we live and drive in.

another observation i had with my old engine (which died a premature death), it was not fitted with a thermostat, it never got above 65C (verified on datalogging software)

i had lousy economy, and a general lack of power

i dismissed it as a wrongly calibrated sensor, the engine eventually packed it in, and upon tearing it down i discovered there was no thermostat fitted, so in my experience, it is better to have a thermostat fitted, it keeps the engine in a close range of temperature, if you have overheating problems with a thermostat fitted, look elsewhere for the cause of them