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Picked up a fresh import 34 GTT last week, now its in townsville, just wondering if anyone knows if the crushing humidity here (generally 75 to 95% all the time) has an effect on the performance or fuel efficiency? If so to what extent? I assume the car is made for cooler and less humid japan, hence the small intercooler so if anyone can help please do. Thanks in advance.

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yeah its common knowledge that temperature would affect performance, humidity on the other hand i am unsure

just use good fuel and ensure the engine is in good working order

the intercooler is not on the factory setup to suit the climate, it is there to reduce heat from the intake charge from the turbocharger. the intercooler is only as a good as the ambient air temperature

yeah its common knowledge that temperature would affect performance, humidity on the other hand i am unsure

just use good fuel and ensure the engine is in good working order

the intercooler is not on the factory setup to suit the climate, it is there to reduce heat from the intake charge from the turbocharger. the intercooler is only as a good as the ambient air temperature

Yeah i know temp is an issue, but cant figure out the humidity, the air is so thick and heavy, i know its not the same but breathing while running here is so much harder than in low humidity i thought maybe it could have a similar effect on a car.

it should be ok, i mean there isn't much you can do it about - ie you can't negate humidity

Yeah true,but i noticed in 1/4 mile time cards humidity is listed as a factor alongside temp, wind etc.

Maybe slightly worse for wind resistance or something, im out of ideas haha.

Thats why I live in Tassie. It's cold ALL the time! ha ha ha. Good crisp air is awsome for power production and throttle response.

It would be hard to know what effects humidity (if any) would have in such a warm climate.

If your worried about intake temps and humidity, throw the car on a chassis dyno in summer and give it a good work out. Then log the coolant, oil and air intake temps as well as afr's/detonation.

If your so inclined- install a larger intercooler and oil cooler with a thermostat. Also if the car is auto, invest in a trans cooler if your going to give the car a hard time.

Edited by XRATED
Thats why I live in Tassie. It's cold ALL the time! ha ha ha. Good crisp air is awsome for power production and throttle response.

If your worried about intake temps and humidity, throw the car on a chassis dyno in summer and give it a good work out. Then log the coolant, oil and air intake temps as well as afr's/detonation.

If your so inclined- install a larger intercooler and oil cooler with a thermostat.

May try that actually, will have to wait until the end of the wet season for a cool day with lower humidity but.Yeah bigger intercooler is on the to do list lol

May try that actually, will have to wait until the end of the wet season for a cool day with lower humidity but.Yeah bigger intercooler is on the to do list lol

Try that.... moving to Tassie, Good plann! ha ha ha.

If your worried about the heat/humidity throw the car on the dyno on the hottest- most humid day you can...

Yeah I know... ha ha ha

I was stationed there for a while. PT on mondays after a sunday session is not fun in 45deg heat and 95% humidity.

Tell me about it, i still have 2 1/2 years here haha, thats what made me think about the car, it affected my performace so much i thought maybe the principal would transfer over?call me crazy

The effect of Humidity on engine performance is not worth considering.

Temperature and air pressure are the main factors that effect air density, which in turn will dictate engine performance. Every degree of temperature increase is equivalent to going up in elevation by 120 feet. A drop in pressure by 1 HPa has the effect of going up in elevation by 30 feet.

A turbo charged car is going to be less effected by pressure changes than a naturally aspirated one, because air is being forced into the manifold at greater than ambient. Temperature is the main thing that will reduce a turbo charged cars performance.

In Aviation we doing not factor Humidity into performance calculations because it is negligible.

The effect of Humidity on engine performance is not worth considering.

Temperature and air pressure are the main factors that effect air density, which in turn will dictate engine performance. Every degree of temperature increase is equivalent to going up in elevation by 120 feet. A drop in pressure by 1 HPa has the effect of going up in elevation by 30 feet.

A turbo charged car is going to be less effected by pressure changes than a naturally aspirated one, because air is being forced into the manifold at greater than ambient. Temperature is the main thing that will reduce a turbo charged cars performance.

In Aviation we doing not factor Humidity into performance calculations because it is negligible.

Sounds pretty definitive, thanks mate.

Humidity does have an effect on any engine.

Those water parrticles are taking up space, oxygen space. The greater the humidity, the less air your engine has to breathe.

Why do you think a dyno needs input from humidty, inlet air temp, etc etc?

It's all compensated for in the dyno's computer package.

Give Trent or someone who does a lot of tuning a PM.

Humidity does have an effect on any engine.

Those water parrticles are taking up space, oxygen space. The greater the humidity, the less air your engine has to breathe.

Why do you think a dyno needs input from humidty, inlet air temp, etc etc?

It's all compensated for in the dyno's computer package.

Give Trent or someone who does a lot of tuning a PM.

Those are the lines i was thinking along.Who is trent?

Yeah the humidity up here is very annoying, walk outside for five minutes and feels like you have walked into a shower. I notice a huge difference from day time to night time driving here, mixture of humidity and air temperature definetely has a very noticable effect.

Edited by PM-R33
Yeah the humidity up here is very annoying, walk outside for five minutes and feels like you have walked into a shower. I notice a huge difference from day time to night time driving here, mixture of humidity and air temperature definetely has a very noticable effect.

Yeah i notice that too, but night here is still hot and humid like a rainy hot day anywhere else hey.now its crazy with all this rain its just getting worse.

Yeah its not the best place for enjoying a modified car. Hopefully if all goes through i should have my car out doing circuit work this year. Really worried about water and oil temps going throgh the roof though. Most of my "spirited driving" is done at night time where i never have an issue with temps, day time however is a bit of an unknown.

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