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well when i posted this...

1 - i had my car for less than a year

2 - i obviously had too much time on my hands

3 - i knew next to nothing about skylines

its amazing how you can learn on SAU... but you'd expect this from a newbie

...now can we close this thread already?

My opinions .

The thermal mass of your typical automotive turbocharger is not that great - meaning the heat that its bearing housing is capable of absorbing . You would not expect to gain any noticable performance through running the core 40 deg cooler . The purpose of having the water jacketed centre section is to prevent the bearings getting hot enough for their lubricating oil to bake on when the engine is shut down - in this situation you also have the thermal mass of the turbine housing and to a degree the exhaust manifold . Provided that coolant through the turbo can be made to thermosyphon the turbos centre section can be kept around 100C or a bit over with the water coolant carrying the heat away into the engines cooling system . The ideal system is one that picks up the coolest water (usually down low on the block ie drain bung hole) and feeds it back in just below where the head feeds coolant back to the radiators top tank . This was how my FJ20 was done and you could plainly hear water boiling in the turbos jacket and hot water/steam bubbles rising up to the head side of its thermostat (which was obviously open) and out to the radiator and up through to the coolant overflow tank . Its critical to have the water lines rise up to the turbo then up to a high point in the cooling system where steam pockets won't allow localised overheating ie VL RB30 head where the radiator is lower than the head outlet . DON'T make the turbo a high point ie water outlet facing down allowing gas bubbles to be trapped in the turbos water jacket because where there's no water there's no cooling . This bubbling/gurgling only happened for a couple of minutes with hotter (less dense and therefore lighter) water floating up and out of the turbo and being replentished by water from the lowest coolest part of the engine . Great system because its fully automatic .

Just in case you don't know FJ20's have the thermostat at the heads water outlet where RB's have it at the blocks water inlet . In theory you could feed water back to the top hose or even the rads top tank if there was a convienent place . You can't do it this way with the thermostat before the upper hose because the turbos water plumbing acts as a thermostat bypass and the engine takes longer to warm up .

I guess if you really wanted to make a small improvement to the cooling system you could place a cooler core between the turbo outlet and the high point but your cooling system would have to be really struggling for it to be of any practical value .

Night all .

lmao WAZ.. Yes I've came across a few of my old threads from time to time. Bit of a laugh.

In theory you could feed water back to the top hose or even the rads top tank if there was a convienent place . You can't do it this way with the thermostat before the upper hose because the turbos water plumbing acts as a thermostat bypass and the engine takes longer to warm up .

Unsure with the R33's but the R32's area already setup like this.

Trace the turbo's water line back to the inlet manifold, it runs through the inlet manifold near the injectors and directly to the top radiator hose; basically a direct path to the top rad hose. ;)

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