GuysOnce your truck is up to operating temps - ~190 ..... and you stop for any reason. Pop the hood and put your hand on the compressor cover of the turbo.How warm/hot ??? curious.thx:thumbup2:

Compressor side, not real hot. Exhaust side, really hot.

Compressor side, not real hot. Exhaust side, really hot.

Its the comrpessor side interested in ...... on my twins its quite warm/hot

--- Update to the previous post...

Its the comrpessor side interested in ...... on my twins its quite warm/hot

Updated in CF also - seems its normal with twins as its already comrpessed from primary ...... wow

I dont have twins but common sense would tell me that the compound compressor would be hotter.

I dont have twins but common sense would tell me that the compound compressor would be hotter.

I agree

Ok let's take this from another angle What IATS are you guys seeing under operating conditions after engine is warmed ?

If I remember right when I had my multimeter hooked up to my IAT sensor my readings were always within about 20 degrees of the outside temp as taken from ISX's chart he made, but this is with the stock HX35Sent from my DROIDX using Tapatalk 2

If I remember right when I had my multimeter hooked up to my IAT sensor my readings were always within about 20 degrees of the outside temp as taken from ISX's chart he made, but this is with the stock HX35

Think I'm close to 130* in around 85 degrees .....

Ok let's take this from another angle

What IATS are you guys seeing under operating conditions after engine is warmed ?

Mine follows +40*F over what ever outside temp is... So like today its 60*F outside so it would be roughly 100*F IAT Temp.

Tough to reduce IAT temps when the intake manifold is heated with 190-195*F coolant.

Think I'm close to 130* in around 85 degrees .....

That's about right... (130 - 85 = +45 offest)

High humidity will make the offset worse.

Also that why my IAT fooler is set for 143*F so it like 100*F day to the engine...

Mine follows +40*F over what ever outside temp is... So like today its 60*F outside so it would be roughly 100*F IAT Temp.

Tough to reduce IAT temps when the intake manifold is heated with 190-195*F coolant.

That's about right... (130 - 85 = +45 offest)

High humidity will make the offset worse.

How accurate is the IAT sensor you think ??

Yeha I was curious with the extra heat comming from the 2x compression what that did to IAT levels ...... sounds like not a whole lot by the time its back out of the intercooler .....

How accurate is the IAT sensor you think ?? Yeha I was curious with the extra heat comming from the 2x compression what that did to IAT levels ...... sounds like not a whole lot by the time its back out of the intercooler .....

Check it... Check your IAT and ECT temp at startup and see if they are the same or close. Or you could break out a DVM and ohm it out... http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/26-engine-systems/59-intake-air-temperature-sensor-iat-sensor [TABLE] [TR] [TD=width: 50%, bgcolor: #3870cc, align: center]Temperature[/TD] [TD=width: 50%, bgcolor: #3870cc, align: center] Resistance[/TD] [/TR] [TR] [TD=width: 50%, align: center] 13°F[/TD] [TD=width: 50%, align: center] 56K ohms[/TD] [/TR] [TR] [TD=align: center] 26°F[/TD] [TD=align: center] 39K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 87ºF[/TD] [TD=width: 50%, align: center] 7.4K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 91°F[/TD] [TD=width: 50%, align: center] 6.8K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 100°F[/TD] [TD=width: 50%, align: center] 5.6k ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 107°F[/TD] [TD=width: 50%, align: center] 4.7K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 112°F[/TD] [TD=width: 50%, align: center] 4.3K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 119ºF[/TD] [TD=width: 50%, align: center] 3.6K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 123ºF[/TD] [TD=width: 50%, align: center] 3.3K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 127ºF[/TD] [TD=width: 50%, align: center] 3.0K ohms[/TD] [/TR] [TR] [TD=width: 50%, align: center] 132ºF[/TD] [TD=width: 50%, align: center] 2.7k ohms[/TD] [/TR] [TR] [TD=align: center] 143°F[/TD] [TD=align: center] 2.2k ohms[/TD] [/TR] [TR] [TD=align: center] 148°F[/TD] [TD=align: center] 2.0k ohms[/TD] [/TR] [TR] [TD=align: center] 163°F[/TD] [TD=align: center] 1.5k ohms[/TD] [/TR] [TR] [TD=align: center] 173°F[/TD] [TD=align: center] 1.2k ohms[/TD] [/TR] [TR] [TD=align: center] 184°F[/TD] [TD=align: center] 1.0k ohms[/TD] [/TR] [/TABLE]

Check it... Check your IAT and ECT temp at startup and see if they are the same or close.

Check IAT and coolant are same at startup ? Should be same ?

One a warm morning above 65-70*F there shouldn't be any grid heaters and both ECT (Engine Coolant) and IAT (Intake Air) should be the same temp. FACT: Both ECT sensor and IAT senor are the same thermosistor. So they both have the same values for resistance and the only difference is the plug and the housing.All this talk about IAT temp no longer even bothers me for fairly stock trucks. The fact is yes after the turbo the air is warmer but after passing through the intercooler it now same temp as the air outside. So now when you enter the manifold that has a coolant passage running with inches of the IAT sensor it hard to get "Cold Air" in the engine. The only way you truly can is mill the entire manifold off, plug the coolant passages and use a racing manifold.But after all my studying of IAT and Intake Air Temps I still say warmer the better for MPG's. When the IAT reaches 100-140*F is the sweet spot for MPG reasons. For racing/performance you'll want to shoot lower like 60-100*F...

One a warm morning above 65-70*F there shouldn't be any grid heaters and both ECT (Engine Coolant) and IAT (Intake Air) should be the same temp. FACT: Both ECT sensor and IAT senor are the same thermosistor. So they both have the same values for resistance and the only difference is the plug and the housing. All this talk about IAT temp no longer even bothers me for fairly stock trucks. The fact is yes after the turbo the air is warmer but after passing through the intercooler it now same temp as the air outside. So now when you enter the manifold that has a coolant passage running with inches of the IAT sensor it hard to get "Cold Air" in the engine. The only way you truly can is mill the entire manifold off, plug the coolant passages and use a racing manifold. But after all my studying of IAT and Intake Air Temps I still say warmer the better for MPG's. When the IAT reaches 100-140*F is the sweet spot for MPG reasons. For racing/performance you'll want to shoot lower like 60-100*F...

perfect

Guys Once your truck is up to operating temps - ~190 ..... and you stop for any reason. Pop the hood and put your hand on the compressor cover of the turbo. How warm/hot ??? curious. thx

It takes no time at all to heat up the aluminum housing from the surrounding block and exhaust manifold once you stop. That being said hot is normal, it's why we have an intercooler. Check this out... http://www.stealth316.com/2-turbotemp.htm

I dont have twins but common sense would tell me that the compound compressor would be hotter.

Only because the air is already warm from the primary compressor, not from the pressure obtained thru the secondary. The temp increase come from compression, and even thou the total pressure is 45 psi the secondary is still only working in a 2:1-3:1 range, so the temp increase is the same if the secondary is fed ambient pressure or 20 psi.

Neat calculator... But for what every reason the final temp numbers don't even come close for high boost number (30-35 PSI) for my truck it report like 170-180*F final temp. Not! I've rarely even seen 150*F (Maybe while using my exhaust brake)...:rolleyes:Mine follows the +40*F offset to outside temp rather closely and change very little while even at high boost. But I'll check again...

The OEM intercooler is probably a lot more efficient than that calculator allow, and item's such as humidity, speed, fan operation, etc will have an effect on the final air temp. Our IC's are HUGE relative to the gasser world, and that's a generic calc.Using that calc I am about 92% efficient at cruise, and 90% at full boost.

It takes no time at all to heat up the aluminum housing from the surrounding block and exhaust manifold once you stop. That being said hot is normal, it's why we have an intercooler. Check this out... http://www.stealth316.com/2-turbotemp.htm Only because the air is already warm from the primary compressor, not from the pressure obtained thru the secondary. The temp increase come from compression, and even thou the total pressure is 45 psi the secondary is still only working in a 2:1-3:1 range, so the temp increase is the same if the secondary is fed ambient pressure or 20 psi.

Good information. I agree, that only because the air is already warm and the secondary compression will warm it further. Also, not to split your hairs but we have an "aftercooler".

Potato...potato (wait, that doesn't work on a keyboard)..Generally I hear intercooler as air-air and aftercooler as liquid-air.

Potato...potato (wait, that doesn't work on a keyboard).. Generally I hear intercooler as air-air and aftercooler as liquid-air.

Technically.....an "intercooler" is between two compressors thus the wording "inter" whereas an "aftercooler" is "after" the compressor. I dont have the squiggly line on my keyboard to say potato either.

Technically yes... just like fast idle vs high idle.