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i have slipped a thermocouple near the plenum and have been taking some readings. i have only had it in for 2 days. i thought it would be interesting to get some numbers before making any changes but i would like to know what is a reasonable temp range (allowing that ambient conditions can vary).

driving to work it has never gone above 20 degrees (usually around 15 deg) except sitting at the lights, 30 degrees on sunday with spirited consistent driving and 48 deg spike on booting it up a hill from a near standstill, as the airflow increased the temp eased back.

at rest you can see temp rising as it soaks engine heat.

is it a front mount cooler? i saw this fellas car at a shop the other day and they had a thermo gun on the cooler pipes and it was actually hotter going into the motor than it was coming out of the turbo due to the way he was running his cooler piping.

Be careful, those guns perhaps tell you the surface temperature of the piping, not the temp of the airflow inside the piping.

sunday was around 18-20 degrees, i had the back seat out of the car installing sound deadening and it was a pretty warm for this time of year.

mornings obviously cooler so i imagine around 10 degrees ambient.

i want to move the thermocouple into the airbox and get some readings from in there later.

it was reading 30degrees on steady/spirited driving on sunday which was approximately 10 degrees above (est.)ambient. at the lights the temp would run significantly higher as the pipework heats up and when you start moving again temps decrease (as expected). the highest single temp it reached was 48 degrees when i got a slight cramp in my right foot up a hill.

how high is too high??

What is a reasonable estimate of intercooler effeciency , 80-85%?

So of you are seeing more then say a 20% diference in temp then perhaps time for a better intercooler, dropping boost or perhaps require better shrouding around the intercooler. So on a 30 degree day shoudl be able to keep within 6-10 deg of ambient prvioded you arent cooking air with your turbo.... on paper it sounds right, dotn know about in practice

I would be very interested to see how the new motor affects the air temp compared to amb temp at the same boost levels.

The new motor obviously breathes much easier due to ~5mm x 2 larger inlet valves, slightly bigger ports etc.

Where can I get the required gear to take the readings I need, and what do I need? Jaycar?

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