S2K Coolant Throtle Bypass

[alpinebs]

Can anyone provide experince realated information to the alleged throtle bypass? I hear it can help keep the throtle body cooler after the enginge comes to temp rather than heating it when the hot cooland flows through it. I also hear it can cause ECU issues.

[smac2K]

Hey man! Just helpin a local out! I live out here on the east side of INDY...hopefully you can meet up with us sometime...

I moved this to this forum, because Dave (Xviper, repiv) is our resident tech and will help you out as soon as he can!

Thanks,

Justin

[repiv]

There's pros and cons to this mod. The pros being that you will keep the TB cooler for longer and even once the temps get up to operating, it will remain about 30 degrees C cooler. The intake manifold typically can get as hot as 70*C once everything heats up. Your coolant temp runs around 95 to 100. The cons would be that if you drive the car in cool or cold temps, it will run poorly and very rich for some time till the TB warms up. The ECU incorporates a "richening" protocol on cold starts. This can include running rich, prolonged air pump operation and timing adjustments.
An easy way to do this "bypass" is to simply block the flow of coolant using a ball bearing inserted into the TB coolant line. This ball bearing is small enough to fit inside the hose, but big enough it won't go into the metal pipe that the hose attaches to.
However, professional Honda S2000 techs indicate that this mod is not worth while as the benefits are so short lived. On the other hand, those who have done this mod have said they felt the car was stronger and didn't suffer from heat related issues. This may have simply been a placebo effect. Only you can be the judge of the results.
Personally, I've been trying to find a valve that I can install in that line so I could open and close the coolant flow from one season to another. So far, I haven't had much luck in finding such a valve with just the right size openings.

[alpinebs]

Thanks for the info. I got a new piece of fuel line hose and routed it between the two locations. I didnt necessarily notice a performance gain but did notice that the intake plenum was much cooler after tooling around noblesville. I will probably replace it to stock diring the winter to help with cold starts. My plan is to do a block back ehaust and wait until i can afford an SC kit for the HP.

smac2K,
Id love to meet up with some fellow car junkies. I saw the ride to Brown county next weekend but my cousin is getting married. Does anyone meet up anywhere around Indy regularly?

[Shahab]

I live in Fishers, and work in Noblesville, I'm sure you'll see me around sometime 08 laguna blue pearl

[hecash]

Thanks for the info. I got a new piece of fuel line hose and routed it between the two locations.

I suggest that you check the temperature rating on the fuel line hose. While you will not normally run this hot, to be safe, I would think that it needs to be rated at least 250 deg F.

[alpinebs]

If my memory served correctly, fuel line hose is backward compatable with anything on a car unlike...say...vacuum hose. I will check to be sure. Thanks for the heads up.

[desmo4]

I tried this and it is a dead waste of time. If you look at the path the water makes through the throttle body you will see it is minimal. I have an imoni and can monitor the intake air temp. I think the Mugen intake keeps the air cooler than the stock airbox and thus keeps the manifold cooler. When I left Glenn Falls last Friday the outside air temp was 50 F and the intake air temp sensor was reading 75 F after a few miles. As I drove South it kept increasing to 104 F when I arrived home in Richmond Va and the outside air temp was 64.

Jonathan