Throttlebody Coolant Bypass

[silverstream]

Hi to all ...

I've recently been toying the idea of a throttle body coolant bypass mod.

However, my mechanic recommend against it, as he mentioned that the throttlebody coolant act as a choke. During warm up, it heats the engine to reach operating temperature (by using a set of mini gear).

Without it, it will take at least 3 times to 5 times longer to warm up and as a result, I will get unburnt fuel and black smoke from the exhaust.

The temperature around my area is consistent 80F-90F ..

Comments ?

[JSIR]

I think he means the cold idle will run longer, the engine still warms up the same as ever. The coolant just helps with cold idle settings, to determine how long the engine runs at cold idle speed and other idle characteristics. I've been running mine in freezing conditions with the bypass mod and it still runs decently, the idle goes down to normal fairly quickly even in these conditions. In your area it should not be a problem at all. Worth looking into IMO.

[!@#$%]

to me this seems like you would get about as much oomph as adjusting your throttle cable. none.

[chakra71]

seems to me that if you're doing the hondata gasket then to actually see any real gain you would need to do this mod.

Without the bypass then the coolant (while still cooler than a hot engine) would warm up the TB and intake air. If you isolate the TB with the gasket and don't allow the coolant in then in theory it should stay much cooler than either alone.

anyone else have any thoughts on the subjekt yO?

:p

[silverstream]

Yes, I went about thinking about it further.

---
Quoted from Hondata:
The cold idle value, which is located under the throttle plate. Late model engines may not have the cold idle valve. The valve consists of a air channel bypassing the throttle plate which is blocked once coolant heats up a wax element. When the engine is cold the cold idle valve will allow a lot of air to bypass the throttle plate, and the idle will be around 2000 rpm. As the coolant warms up the cold idle valve will slowly close, bringing the idle speed down.
---

There is a valve below the throttle plate, so I assume it is the same as above.

The TB Cold Idle Valve is wax element, as such, when the TB reached effective operating temperature, the Cold Idle Valve will be shut.

Now, thinking back .. in order for the wax element to be heated and expanded, the engine still need to reach operating temperature.

As such, either doing a bypass or not, the TB will still get heated up to the required temperature ...

So,we are back to square one ?

Am I right ?

[chunky]

i have yet to see dyno proof of a TB coolant line bypass gaining HP.

till then, i'll leave it the way it is. Even though I live in GA, I'm not too thrilled with the thought of my throttle plate sticking shut.

[JSIR]

I can't say that I've seen any gains from bypassing the coolant lines in my last dyno runs, even though it makes sense to reduce heat in the TB/manifold area. I think the TB and manifold still get excessive heat from the front rad area as something still makes the idle control circuit activate to warm idle conditions even without coolant in the wax plunger sensor of the IAC valve.

[myeverlovinsir]

Originally posted by chunky
i have yet to see dyno proof of a TB coolant line bypass gaining HP.

till then, i'll leave it the way it is. Even though I live in GA, I'm not too thrilled with the thought of my throttle plate sticking shut.

If you've started it in cold weather and your tb plate did not stick, it would not suddenly start to stick due to the bypass mod - its not gonna get any colder anyway. You would idle longer until the sensor is wamed ambiently, and be just burning extra gas. I agree that there would be no gains involved.

[silverstream]

Yeah ... that's my sentiment too.

Eventually, the TB will reach ambient temperature, so there wouldn't be much gain.

[chunky]

Originally posted by myeverlovinsir


If you've started it in cold weather and your tb plate did not stick, it would not suddenly start to stick due to the bypass mod - its not gonna get any colder anyway. You would idle longer until the sensor is wamed ambiently, and be just burning extra gas. I agree that there would be no gains involved.

well, with the air flowing through the TB, it can actually get to BELOW ambient temperature while running when it's really cold.

But you're the cold weather man, so i'll take your word for it. :D

[Hondata]

Anything that reduces the temperature of aluminum that the intake air passes over will help.

[silverstream]

Actually my thought is, if I do the bypass, I get slower warm up.

HOWEVER, if eventually the TB will eventually be heated to the same temperature of that before the bypass, then isn't it the same as not doing a bypass ?