Hey I have a s5 turbo with cx racing radiator and e fan and NO thermostat and the stock gauge still goes up to normal operating temp just below half way
Any ideas?
Thanx
P.s. I know the stock gauge sux but can it be that off and my car is carb turbo no wiring harness hooked up

 

Why would it not go up to normal operating temps? And why are you running without a thermostat?

 

Couple of things here.

First, put a thermostat back in the car. These engines have a bypass cooling system. If you don't have a thermostat you can not get full flow through the radiator. You have only about 20% of the cooling capacity if the thermostat is taken out.

Second, only use an OEM thermostat. Period.

Third, the stock S5 gauge has a clamping circuit. It does not read in a linear fashion and so cannot tell you anything helpful about the actual temperature of the engine. It reads normal at about 180* and does not rise any more until the temps get to about 240*. Really. So get an aftermarket gauge.

 

^ What about s4 gauges?

 

+1 to everything Jack said.

The S4 temperature gauge is linear from about 160 - 250 F. The S5 gauge is a 3-reading warning light: cold, warm & rebuild.

 

I'd still like to know why you thought running without a thermostat was a good idea? It's there for a reason. And as Jack stated, its a bypass cooling system. You're a lot worse off without one.

 

The answer is likely that people simply assume the thermostat is a restriction in the circulation of coolant to the rad - remove the restriction, leave a bigger hole, that's always open, so coolant can flow sooner and more freely to the rad, and therefore have everything run cooler. They fail to understand that the thermostat functions more like a switch on a rail line, directing the flow back through the engine when it is not warm enough, and out to the rad when it is.

And +1 to jackhild59's response, as well.