zeroptzero

I got myself a scan gauge today from crappy tire and did some preliminary runs/testing with my car. I know some others have used these devices and was wondering how their intake temps matched up in different driving conditions. Here are some initial observations on my car.

When I first plugged in the gauge after driving to the store and purchasing it and the car sitting fully hot for about 20 minutes in the parking lot with the hood closed the intake air temp read 134 degrees before I started the car up. With an ap1 you are really measuring intake manifold temp when the car is fully hot, not just air temps as the temp probe sits deep within the metal manifold.

With ambient temps around 70 degrees my car was reading about 92 degrees in steady state city driving about 70 km/hr with the throttle partially open in cruise conditions. In slower city stop and go driving conditions around 50 km/hr temps rose to about 105 degrees. In highway driving conditions of 120 km/hr I saw temps dropping down to 85 degrees. The longer I drove on the highway with steady state conditions the lower the air temps got as the intake manifold cooled off. Air temps were cooler with the throttle open, and they climbed as the throttle was closed (as the manifold heated up), the change was very quick as the throttle plate closed.

Tomorrow I will take some readings starting with a cold engine and it will be more representative of actual air temps until the manifold heats up. Unfortunately once the engine heats up on an ap1 you are getting readings based on manifold temps as all the metal heats up. I think if I could have driven the car for another 15 minutes on the highway today I would have been very close to ambient temps, but starting out with a manifold at 134 degrees had an effect during the relatively short 10 minute drive.

My setup is an ap1 with J's intake snorkel that runs to the front bumper, stock air guide, stock air box and filter, exposed Mugen header (no heatshield). I didn't measure coolant temps but I might try that tomorrow too as I learn how to use this device a bit better. I have a mishimoto aluminum radiator with stock temp sensor, stock thermostat, oem fans.

If anyone else has some information from their car please post it up. Thanks for reading.

starchland

I do.

84 C coolant most of the time with the exception of hard driving it will go to 88-90ish

IATs are highly dependant on ambient temps and whether the car is moving or not. Today I was seeing 40s roughly around town. When the car is moving, the temps drop significantly. Fipk coated in reflectagold & Tb bypass.

FluKy15

Shit I forgot to do the TB bypass

Im going to be watching it on my netbook with my flashpro during my trip. Ill post up my results.

zeroptzero

Thanks for the reply, I'll switch mine to celsius next time I run to compare numbers.

I'm liking this scan gauge thingy,

myflys2k

My temps with supercharger and stock intake manifold gasket I see the same temps as you Joey. WOT on a 70F day drop the temps down quick

When I had the hondata intake manifold gasket (recently removed) my intake temps were way more constant and cooler. there was nothing wrong with the IMG but the fear of it melting on a track day wasn't worth it.

zeroptzero

I got a chance to take the car out this morning with a cold engine. Exterior temps were 60 degrees.

Driving on small rural road 50 mph the temps steadily rose up to 90 degrees, then hitting the highway temps dropped to 80 degrees. Getting into some city driving with stop and go traffic temps rose to 100 degrees. Once the car was moving in city driving 30-40 mph temps would drop to 95 degrees. Getting back on the highway temps dropped to 85-89 degrees. Then driving through my residential neighbourhood the temps rose to 110 degrees with speeds no more than 20- 30 mph.

A big factor in driving is the position of the throttle plate, going WOT immediately reduced temps up to 10 degrees very quickly, I think throttle plate is even more effective than just vehicle speeds. At closed throttle the temps jump quickly, due to the position of the temp sensor being in the manifold.

As I got home I measured various parts of the engine. The intake manifold was 110 degrees which equaled exactly what I saw on the scan gauge at closed throttle. The rubber intake hose was 90 degrees, the intake box measured 80 degrees, my snorkel measured from 60-70 degrees and was very cold. The hottest part of the intake box was the resonator air-chamber that sits in front of the radiator fan, one thing I'm going to do is block the hole inside the airbox so it doesn't take air/heat from the resonator chamber.

My water temps were 180 degrees the entire drive, about 20 minutes. The intake manifold temps rose by 50 degrees, the intake box rose 20 degrees, my snorkel was feeding ambient air temps which brought down manifold temps by up to 30 degrees with the throttle open in the best of conditions.

Highway driving temps were 20 degrees over ambient, driving on a rural road in steady state driving temps were 30 degrees over ambient, city low speed stop and go driving conditions temps were 40-50 degrees over ambient.

o'malley_808

Interesting. So are you thinking of mods to lower your intake temps or just observing it more or less for curiosity? I havent payed too much attention to my IAT just since I have all the possible cooling mods and there really isnt anything more I can do.

My coolant temp on the other hand is a different story lol. I swear I look at that more than the road. It drives me mental!

zeroptzero

I was pretty much interested in air intake temps, since I installed my J's Racing snorkel the car has run much more consistently throughout the daytime, much less afternoon heat soak bogging going on, so I was curious to see how the intake temps measure up. I didn't get a chance to measure the temps before the snorkel installation.

I wasn't too concerned with coolant temps as my mods are fairly simple, my coolant temps are pretty much pegged at 180 degrees all day long when fully warm.

This ap1 intake manifold mounting of the air temp probe really messes up the readings of air intake temps though, the heat of the manifold plays with the readings quite a bit and throttle position has a big impact on the air intake readings. The higher the air flow through the manifold the cooler the temps.

zeroptzero

I was pretty much interested in air intake temps, since I installed my J's Racing snorkel the car has run much more consistently throughout the daytime, much less afternoon heat soak bogging going on, so I was curious to see how the intake temps measure up. I didn't get a chance to measure the temps before the snorkel installation.

I wasn't too concerned with coolant temps as my mods are fairly simple, my coolant temps are pretty much pegged at 180 degrees all day long when fully warm.

This ap1 intake manifold mounting of the air temp probe really messes up the readings of air intake temps though, the heat of the manifold plays with the readings quite a bit and throttle position has a big impact on the air intake readings. The higher the air flow through the manifold the cooler the temps.

o'malley_808

If you check the FI section they were just recently having a debate on this. They basically said that the AP1 IAT is an accurate reading and that the heatoaked IM is super heating the air coming in. They said that explains why when you get on the throttle you can watch your IAT's drop as you are literally cooling the IM with air...