IAT Whipple vs E-Force

[03ss]

Originally Posted by Whipple Charged

Here you go guys, run on the dyno, this is a modified 6.2L Escalade motor. Custom cam, ported heads and dyno headers. The IAT2 temp shows 15-20deg F over the cell temp. This was with the GM 3/8" NPT screw in style sensor which reads a bit higher since it picks up manifold/head temp from the threads.

http://pdfcast.org/pdf/whipple-175ax...c-dyno-results

http://pdfcast.org/pdf/whipple-sc-dyno-results

If you dont mind me asking what calibration are you using for the data loggin of this style sensor? Also, what objective data do you have proving your claim that the screw style sensors read higher due to heat picked up from the housing of the sensor?
I have used these sensors thoughout many applications in the past and I have not seen any reason to question the reading and when it comes to the calibration I have found exactly the opposite of your claim that "This sensor, when used with the stock transfer function reads slightly higher then the grommet style sensor." I have found it necessary to tune in a new calibration when compared to a factory Cartridge style maf IAT calibration as it would be reading lower than actual and in reguarding the GM Grommet style calibration to actually be fairly close to the factory calibartion.
Please correct me if im mistaken but I just want to make sure the correct information is being represented.

On another note I do find it odd that both of these test conducted in these PDF's are before you post where you state that "Thus, its not required to monitor post SC." And there for I ask if it is not important why were you measuring it then?

Originally Posted by Whipple Charged

...standard screw in temp sensors are not as accurate (pickup all the heat from the engine and under hood) and most have different transfer functions. When your in this area with our twin screw, the temps very rarely change and gives almost zero tuning ability since there's almost no swing in temps. Thus, its not required to monitor post SC.
...Ours, with the oversized IC and SC design stays with 10degs of ambient up to 12psi when measured in the air stream....

I also would like to note the general setup the would be run on an engine dyno would be to pump cold water directly from the tap as opposed to using the actual pump and heat exchanger that are part of the kit installation which could net very different results. While the results look good you have to remember that these are most likely the best case senario, if that.

[acric5]

The measured mass of Oxygen is determined at the inlet and is unchanged there after. mass at the air inlet is the same as mass at the heads. It does not mater how the pressure and temperature changes through the blower or intercooler. If we are well tuned using the MAF then as the temperature/humidity/pressure varies at the MAF (air inlet) the relative changes at the head inlet port can be calibrated and the air temperature at the heads is a redundant measurement.

We are fueling to accommodate the Mass of O2 not the air flow because air flow varies once past the intake due to pressure /temperature changes. Once the tuning is correct based on the MAF, calibration for air temperature is a relative function where ever you choose to measure it.

Heat soak is not a consideration when the engine is flowing moderate amounts of air. However if the inter-cooler fails, then all bets are off.

the engine runs in closed loop most of its life when the manifold is under vacuum, this may preclude moving the temperature sensor to the manifold which would interfere with the restart EPA requirements.

but then again I could be wrong.

Originally Posted by Duke

Maybe I can simplify this from strictly an engineering perspective.

The IAT at the air box determines the mass floww of air. The temperature after the intercooler determines the volume flow of air into the cylinders. The lower the temperature the lower the volumetric flow rate. Since the blower is positive displacement and the cylinder volume is fixed, the intercooler outlet temperature sets the blower discharge pressure.

All things being equal, lowering air charge temperature to the cylinders will produce the same horsepower with less boost pressure.

[Whipple Charged]

Originally Posted by 03ss

If you dont mind me asking what calibration are you using for the data loggin of this style sensor? Also, what objective data do you have proving your claim that the screw style sensors read higher due to heat picked up from the housing of the sensor?
I have used these sensors thoughout many applications in the past and I have not seen any reason to question the reading and when it comes to the calibration I have found exactly the opposite of your claim that "This sensor, when used with the stock transfer function reads slightly higher then the grommet style sensor." I have found it necessary to tune in a new calibration when compared to a factory Cartridge style maf IAT calibration as it would be reading lower than actual and in reguarding the GM Grommet style calibration to actually be fairly close to the factory calibartion.
Please correct me if im mistaken but I just want to make sure the correct information is being represented.

On another note I do find it odd that both of these test conducted in these PDF's are before you post where you state that "Thus, its not required to monitor post SC." And there for I ask if it is not important why were you measuring it then?




I also would like to note the general setup the would be run on an engine dyno would be to pump cold water directly from the tap as opposed to using the actual pump and heat exchanger that are part of the kit installation which could net very different results. While the results look good you have to remember that these are most likely the best case senario, if that.

Here's the thing, were a SC mfg and have 3 dyno's and every conceivable testing device needed for development. We've run IAT's, many different ones, in many different applications. I can tell you that moving the sensor in different locations of the manifolds will change your temps (in an aluminum intake). Most of the sensors pickup residual heat unless isolated. Furthermore, if your not in the proper air stream, your not gonna get the actual air temp. Different parts of the intake flow more than others. The tip of the sensor has to be directly in the airstream, not just the intake.

The rubber grommet stock sensor read 8-10deg F consistently cooler (vs 3/8" NPT screw in sensor between 5/7) while a probe under the core read 3-5deg F cooler yet. Probes inserted in each runner, in the middle of the air stream read 1-2deg F hotter then the probe under the core making them almost identical to the grommet style sensor (when installed in air stream).

As for the water feed, we used a closed system to simulate car conditions. For marine, we use raw water.

I'm not sure why its odd that we test? You keep misrepresenting my statements. I said that its not required, as in not mandatory. Clearly the systems run well and have proven themselves so this is not false information. What I also stated is that its best to have both temps, IAT1 and IAT2 like all supercharged Ford systems and most of GM's. All of our Ford Racing systems, co-designed and tested with Ford that work without the temp sensor in the manifold. After 5000+ systems, it really hasn't been a problem. But, if customers and tuners want to install a IAT sensor in the manifold, the port is there. And anyone who has done it so far as witnessed that the temps are incredibly cool and very consistent. And just to be clear, reading temp at the MAF is not wasteful, in many air kits out there get very hot because they suck up temp from the engine bay. The fan system pushes air to the sides. If this happens, it retards the timing.

[RAYSRT8]

It's all about your personal choice and for me it was Edelbrock and at 639RWHP with the SC stock pulley I would put it up against any supercharger out there...But that was my personal choice...