It's actually NOT good to do this 'coolant bypass' free mod. The coolant running through the TB serves a purpose. That valve that the coolant runs into and out of is waht controls how fast your car idles. When the valve is open(the coolant running through is cold, or not at operating temp) the car idles higher, at 1500rpm, that valve is why the car idles up while it's cold, if you take the coolant away, the car will never reach temp, and will always idle high. When the coolant is at temp the thermo valve closes, and the car idles normal.
no, its a good idea as long as you block off the ports in the fast idle thermo valve... then your idle will be normal. if you do the bypass without blocking off the ports, then your idle will fluctuate from like 1k to 2k.
prelude styl, what you said about always idleing high is not true at all.
The engine still senses the car is not at operating temperature somehow besides that valve. I have the bypass done and when I first start the car in the morning it will sit at about 800 for roughly 3 seconds, then go up to normal rpm for warming up, about 1500. Then it idles back down like normal when it reaches operating temp.
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