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intake air temperatures?


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Hey guys just finished installing the turbo on my mighty max and just wondering what you guys are kinda ball park running for intake air temps say

 

Sitting in traffic in a spring day

 

Cruising at highway speed on a spring day

 

Aggressive driving

 

I kinda have a odd set up and with out some base numbers I can't tell how efficient I am running

 

Thanks

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What are you seeing?

 

Highway cruising should be within a few degrees of ambient, sitting in traffic a few more, aggressive driving (boost) will shoot it up into the 100's F.

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I am just running a stock turbo set up at about 7psi. I am running a top mount intercooler passenger front side of engine bay with a little hood scoop and sealed nice against the hood.

 

Nice short pipes makes for nice fast spool...I wanted all low end engine almost never sees above 4500-5000rpm.

 

Sitting in traffic on say a 10 Celsius day it will great soak to about 40-45 but that's cause i have not got my intercooler fan installed yet

 

At cruise maybe 20-30 Celsius and prob 30-40 under hard boost.

 

Sounds like I have some room to improve...some more heat shields and the fan I think will go a long way...

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I agree that you have some room for improvement. Like Scott said at cruising you shouldn't see more than 15C on a 10C day. Just out of curiosity why would you run a top mount?

I actually see my temps drop under hard load due to the water/methanol injection. So that's always an option for you too. Although if you get more airflow over the IC you wil probably be OK.

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I did a top mount for a few reason..keep it out of the mud....almost no room for a front mount...short pipes for faster spool.

 

If it was a 2wd built for performance I would deff front mount but for this truck top mount seemed to be the best

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  • 1 year later...

Piggybacking: My air temp is very constant compared to what everyone here is saying. It was right around 95F today with an ambient of 70F. When I start the car it will be around ambient. Under boost it doesn't really go up.

 

Does it matter where its placed?. mine is in the OVCP.

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This is the MPI/Standalone sub forum Speedy, lol.

 

Mike it does matter where it's placed, I'm sure you're getting some heat soak. Not really an issue though unless its not running right. Is it an open element sensor or closed?

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/facepalm So true Scott lol. Ok so let me try and redeem myself with this question. How does the ecu measure that? I guess I don't typically hear about air temp sensors being used. Maybe they just arn't mentioned a lot?
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The intake air temp is a big deal for proper fueling, especially when using speed density as the fuel equation starts with the ideal gas law, PV=nRT. Pressure, Volume, air mass, a constant and air Temperature, without proper air temperature reading you will get poor results as the ECU isn't calculating air mass correctly. DIY sells both the open element and closed, it would be worth your time to take it out and look, the closed element will look like a coolant sensor (because it is) and the open will have a plastic cage around the element with holes for airflow. If its not an open element I'd get one, note that the pigtail is different between the two so you can't cross connect your CLT and IAT.

 

The factory MAF has an IAT in it but for speed density its on the wrong side of the turbo, it's OK with MAF but MAP (speed density) needs to know the air temp with a lot more precision and closer to if not in the intake. The first Starquest I megasquirted I put the IAT right where yours is, where the factory put it on the 86's, but I moved it in short order because of heat soak. The problem wasn't so much a running issue as a hot restart issue, it was just hard to start since the IAT was telling the ECU the intake air was 180 F. The MS2 and 3 firmwares have ways to tune around that issue but that was an MS1 and all those issues went away when I moved the IAT to the post-intercooler hard piping at the front firewall.

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I checked it and its the closed type with no holes. I would have never figured that out, thanks Scott !

 

I'll order up the open type sensor and pigtail and go from there. It'll be nice to be able to fine tune it better...

 

Doing some searching it looks like there are some settings for hot restart if heatsoak is an issue. Maybe I can figure that out, if not I'll move the sensor like you suggest.

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I checked it and its the closed type with no holes. I would have never figured that out, thanks Scott !

 

I'll order up the open type sensor and pigtail and go from there. It'll be nice to be able to fine tune it better...

 

Doing some searching it looks like there are some settings for hot restart if heatsoak is an issue. Maybe I can figure that out, if not I'll move the sensor like you suggest.

keep the closed for spare, its also used for a coolant temp sensor lol

 

try and add some shielding between the motor and intercooler if possible, there is ALOT of heat rising off the motor, especially if you dont have the heatshields on the turbo and manifold

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  • 3 weeks later...
Yeah a lot of people end up putting the IAT sensor in their IM. Mine is in the charge piping leading to the TB about a foot away. It seems to generate good numbers and doesn't have too much piping for heat soak to set in. In the future I will probably put my meth injection nozzle where my IAT sensor is and move the IAT sensor to the IM itself so it knows what the temp difference is when the methanol is being introduced.
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It's a matter of opinion. If you are putting the meth injection in solely as a safeguard against detonation then its placement in relation to the IAT isn't critical. Since most people like to use it as a power booster as well, allowing the system to know the correct IATs and tune for more timing advance is desirable. I've used it both ways with good success and prefer to have the nozzle in front of the IAT for tuneability, but just wanted to throw it out there. Edited by polarisman14
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Yeah a lot of people end up putting the IAT sensor in their IM. Mine is in the charge piping leading to the TB about a foot away. It seems to generate good numbers and doesn't have too much piping for heat soak to set in. In the future I will probably put my meth injection nozzle where my IAT sensor is and move the IAT sensor to the IM itself so it knows what the temp difference is when the methanol is being introduced.

you dont want it IN the intake, i tried that, out of boost driving IAT reads 130f+ and goes down as you are in boost, idling i have seen it hit 140f

You absolutely want the IAT sensor after the method nozzle. I made that mistake when I first installed water/meth. Having the sensor post meth nozzle makes for much easier fuel tuning.

It's a matter of opinion. If you are putting the meth injection in solely as a safeguard against detonation then its placement in relation to the IAT isn't critical. Since most people like to use it as a power booster as well, allowing the system to know the correct IATs and tune for more timing advance is desirable. I've used it both ways with good success and prefer to have the nozzle in front of the IAT for tuneability, but just wanted to throw it out there.

 

i think you are both saying the same location, but saying it differently

 

 

turbo - piping - intercooler - piping - Water Inj - IAT - TB

 

is how im reading from both of you

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