JAMMNN

I would like to know what are the danger levels for Intake Temps.

Thanks

rynberg

Unless you are in a traffic jam for over an hour on a 100F day or you are tracking the car with the stock IC, don't worry about it.

What temps are you seeing?

ZeroBanger

I used to get a bit worried when my intake temps exceeded my water temps.

FormerPorscheGuy

95c is the highest I see.

rynberg

Yikes! I hit that once when stuck in a traffic jam for over an hour in 100F heat. The highest I've hit at the track has been high 60sC at 13 psi.

FormerPorscheGuy

Oh sh@t, I feel like a dumb a$$ now. I miss read the post, sorry everyone.

My water temps don't get above 95c

My air intake temps are between 40c and 60c, this is Houston and it get hot here. Heat soak is 70c when its over 100c outside.

Sonny

100c outside? Damn, I didn't know it got that hot in Houston.

Sonny

RotorJoe

Just go easy on boost if you see temps extremely high intake temps. The highest I have seen has been around 50 or 60C. That is on a hot car with heat soaking. In traffic on hot days I see around 40 C. Once the cars starts moving things come down.

FormerPorscheGuy

Ok, too much beer tonight for me, I need to go. lol.

dclin

iTrader: (4)

It's the humidty, ya know.

twokrx7

iTrader: (1)

Be careful if you park it hot and then get in. Wait till the intake air temp dropps before you go into boost as the engine will lean out under these conditions. This condition is worse with the sensor in the stock location.

I've never seen mine hit 60 except for a heatsoaked condition when the car is shut down and parked for a bit then restarted.

FD_Newb_1974

All these discussions of AIR intake temperatures would be more helpful if people included their mods, specifically intercoolers.

Sonny

60 deg C ain't got nothin' on this:



This is what boost is like with NO intercooler. I don't recommend it.

Sonny

SkywarpR

Agreed, see my sig for mods...

I have the stock intercooler, and I typically see temps in the 40's. It goes up higher on a hot day. With heat soak, I might see temps all the way up to the 70's.

KaiFD3S

iTrader: (37)

I have a Greddy SMIC intake temp are between 40C and 55C,

t-von

iTrader: (8)

Is this on a rotary? Did you bypass your IC just to see how high the temps would get under boost? At what psi is this chart based on?

twokrx7

iTrader: (1)

lol, "... is that on a rotary", didn't know rotary had VTEC ... lol

rceron

Why would you have a lean condition when air is hotter than normal? Aren't lean conditions of a function of insufficient fuel and/or too much air? When the air gets warmer it is LESS dense and thus technically there would be less O2 molecules. Heat soak and high temps can definitely cause detonation/pre-ignition but I'm not sure about a lean condition.

Maybe the computer reduces fuel when it reads higher temps? Still doesn't make sense.

R

rynberg

The PFC (and most likely, the stock ecu) reduces fuel when it measures intake temps above 45C(?). However, the amount of reduction is only 3% at maximum -- if you are tuned that close to the edge, well.....

Besides, Zerobanger has both a relocated and the stock IAT sensors, I have seen that the relocated heat sensor gets heat soaked as well. Also, since the UIM is really that hot, it stands to reason that the air is getting heated up as it enters the engine.

All that said, if you get stuck in hot day traffic and your intake temps hit 80C or more, it's best to not go WOT until the temps have gone done a bit -- just to be safe.

ZeroBanger

"Water Injection"

skotx

I believe the issue here is as follows:

You drive the car, park it, it gets heat soaked. Thirty minutes later you hop back in and take off. Let's say the IAT is reporting back to the ECU that the temp is 70C, so the ECU pulls fuel. In reality, the air coming in is 40C, but the stock IAT reacts very slowly and is heat soaked anyway. Colder air is denser, the ECU is pulling fuel, thus you're running lean.

As you can imagine, this problem gets more severe the colder it is outside, i.e, the greater the difference between the reported IAT and the actual incoming air.

Beast From The East

Hey, rynberg, I know you've been around the rotary block, so you may know this, but just to be sure, the amount of fuel correction for the PFC is at 6 different points (from -30 C to 80C), and you can adjust those settings using the datalogit software (just about all of us using datalogit have). At 45C the default adjustment is ~ .98 (roughly 2 percent reduction in base fuel map), because the default settings for 50 c are .984 and at 30C they are 1.012. The PFC just uses simple extrapolation between the points.

I have no idea what the stock ecu is set for.

rynberg

Yeah, I knew about the discrete points, the extrapolation, and approximately the maximum percentage of fuel reduction at 80C, but I didn't want to get into all that... Thanks for posting that though, it's damn good info. I still don't have a datalogit yet, so I'm just at the stock PFC settings for those types of settings.

Beast From The East

Dude (help, I'm stuck in the 80's) - with all you know and how much you've invested in your ride, you don't have datalogit?



Granted, in San Lorenzo you're in areas that are fairly temperate, but if you ever go to where it can get cool (saw in the 20C area) and you go for boost, you run some risks......

cewrx7r1

iTrader: (2)

Why isn't this thread in the PFC forum where it should be.

I have a Blitz FMIC and live in Hosuton. My air temps are never over outside air temp + 10 in celsius, unless from heat soak. My ATS in located in the outlet pipe from the FMIC.

I have also replotted my INJ vs Air Temp Map for all three seasons that we have here in Houston.

That is hot as hell, warm, and cool.