bikky

For those of you that run in car monitoring. What's the difference to your ext temp compared to intake temp?

It's winter here in the UK and I noticed the other day, at 40mph, with outside temp of 8-10 degrees, my intake temp is approx 35 degrees. At standing traffic it goes up to about 50 degrees.

Today at 1-2 degrees and at 60mph, I was seeing abuot 20degrees intake temp.

My concern is that I'll cook in summer.

Is this right, or is it a by product of the K&N FIPK, and I need to rid myself of it?

Comparisons to standard box would be nice.

Thanks

tehlonz

Are you using the stock IAT for datalogging?

zeroptzero

Is your IAT sensor on the manifold (ap1) or the intake arm (ap2) ?, that makes a difference on the readings you get.

Intake air temp readings are largely dependant on throttle opening on an ap1 setup where the sensor is in the intake manifold. The wider the throttle is open and the longer it stays open the lower the temps are. As soon as the throttle plate closes or is reduced the higher the temp reading will be. It is largely affected by the temp in the manifold. The incoming air cools off the intake manifold so you will see temps decrease, as soon as the throttle plate closes the intake manifold temps climb rapidly.

On my ap1 with a Mugen cold air intake driving in steady state highway conditions my temp readings are about 12-19 degrees above ambient, this is in perfect driving conditions where the throttle remains open for long periods of time. In mixed driving it will increase to 30 degrees over ambient as you encounter closed throttle conditions, some stop and go driving combined with steady state driving in town. In slow bumper to bumper driving conditions it can spike up pretty high, but as soon as the vehicle accelerates over 50 km/hr the temps start to decrease again.

It's not unheard of to get spikes as you have listed 50 degrees +, in very slow driving conditions, but once the vehicle is moving it should drop. If you continue to get higher temps as the vehicle is moving in steady state conditions then you need to get a better cold air source.

I've never logged temps in an ap2 setup with the temp sensor in the intake arm so I can't comment on that.

bikky

Thanks for that. It's ap1, I'd seen similar with my astra and k&n, but not as much difference as this one.

At least I know.

zeroptzero

In the summer months the numbers will obviously be higher, but it will be similar in terms of the increases over ambient temps. Also in the summer months the temperature of the air coming off the hot asphalt about 2-3 feet above the roadway can be quite a bit hotter than the outside air temp. Lots of factors to consider. I recall one very hot summer day I was recording intake temps on my ap1 around 119 degrees F with exterior air temp of 90 degrees F, but when I stopped to measure the temp coming off the asphalt it was well over 110 degrees and that's where many cold air intakes obtain their source of air.