[BrandanK]

My experience isn't exactly the most current, but years ago when the GM 3800 SC cars were big (Grand Prix GTP, Impala SS, Regal GS) I ran an Alky Control kit on my GTP.

I had indicator lights to tell me when the pump was running and I always monitored the light. The issue was that I was out of town once and my cousin's car broke down. Turns out he didn't know anything about the indicator light on my car when he borrowed it. Even though I told him not to beat on the car, he decided to hot lap it and it chipped a piston ring land. The alky pump had locked up and he had no idea.

All could have been prevented if he would have just left his foot out of the gas or if I would have told him he could not drive the car while I was gone.

Long story shorter; yes, they can and do fail, but as others have mentioned, it is all about how you handle the risk. I'm sure the pumps and kits are considerably more reliable now than they were 10-12 years ago.

BK

[EDFHOBBIES]

Originally Posted by JANNETTYRACING

With a properly working intercooled supercharger there is no concern of High IAT.

invest in the LT4 fuel system for an OEM like reliable no baby sitting 600 RWHP.

Ted.

Question Ted could you please share more info on this?

What Is a proper iat reading at the following speeds, conditions, or power levels?

Let's say you have 600 rwhp hp high compression LT1 stock motor with outside temps being 100 degrees on the nose! And zl1 with lower compression same scenario with 800rwhp

1. Cruising temps iat 1 reads the same the temp as outside 100 degrees what is proper for LT1 and a LT4 to read on Iat 2?

2. Under load during run at the track or 30 to 145 roll? Again 100 degrees outside what would be critical if it climbed to make another roll or pass?

3. Can you clear up confusion on iat readings 1, 2, 3 where the temps are measured at (location)

Iat 1 where is that located?
Iat 2 where "
Iat 3 where "

I've noticed that 2 of the 3 sensors read the same I believe 2 and 3.

Thanks for the help Ted

[KingLT1]

There isn't really anything "critical" per say. If MAT's get above a certain temp the ECU is only going to allow so much timing advance to protect the engine. The hotter the MAT the less timing the engine will be fed in order to keep KR at bay. Engines running E can run higher temps without pulling timing vs pump gas. This is all controlled by the IAT vs Spark table. Mine doesn't pull any timing until MAT reaches 154 degrees. I don't believe I have seen it get that high yet but it doesn't reach 100 here...usually 88-92 degrees in the summer. Even after a hard pull at those ambient temps my MAT are hovering around 128-135. I am sitting between your 600 & 800 goal posts for power with high compression running E50.

[EDFHOBBIES]

Originally Posted by KingLT1

There isn't really anything "critical" per say. If MAT's get above a certain temp the ECU is only going to allow so much timing advance to protect the engine. The hotter the MAT the less timing the engine will be fed in order to keep KR at bay. Engines running E can run higher temps without pulling timing vs pump gas. This is all controlled by the IAT vs Spark table. Mine doesn't pull any timing until MAT reaches 154 degrees. I don't believe I have seen it get that high yet but it doesn't reach 100 here...usually 88-92 degrees in the summer. Even after a hard pull at those ambient temps my MAT are hovering around 128-135. I am sitting between your 600 & 800 goal posts for power with high compression running E50.

I was just wondering I assume sitting on the dyno even with fans is noting like the flow driving can produce as far cruising temps I would say the dyno fans have a huge advantage over sitting in traffic though.

Edelbrock 2650 Zl1

Cruising in 100 (car temp on radio matches IAT 1) degree weather I see 108 on IAT 2. If I do a pull to 6900 they fall to 106 and if I do a 3 and 4 gear pull they go ambient out side temp maybe 1 or 2 degrees below then about 1/8th mile later they are back between 8 to 10 degrees above ambient (outside temp)

Sitting at a light in 100 degrees or stop n go traffic with no air movement I see the IAT 1 climb to 116 IATs 2 I've seen 160s. I don't think the fans are on unless I'm running the AC and not sure it would matter. After about 1 minute the IAT 1 returns to ambient or outside temp it may not even be 1 min as soon as it gets some air flowing. The IATs 2 takes about 5 min at 60 or 70 mph to go back to 8 to 10 degrees above ambient.

On the edelbrock 2300 SS camaro

My IAT 1 isn't reading the same as outside temp its always about 8 degrees off(higher) cruising. I need to see if it matches cold. Just cruising its 135 average haven't logged enough to see what it does on hard passes sitting still it gets pretty dang hot maybe 160 plus.

I wonder why the IAT 1 is off or why its calculating different?

[JANNETTYRACING]

Originally Posted by EDFHOBBIES

Question Ted could you please share more info on this?

What Is a proper iat reading at the following speeds, conditions, or power levels?

Let's say you have 600 rwhp hp high compression LT1 stock motor with outside temps being 100 degrees on the nose! And zl1 with lower compression same scenario with 800rwhp

1. Cruising temps iat 1 reads the same the temp as outside 100 degrees what is proper for LT1 and a LT4 to read on Iat 2?

2. Under load during run at the track or 30 to 145 roll? Again 100 degrees outside what would be critical if it climbed to make another roll or pass?

3. Can you clear up confusion on iat readings 1, 2, 3 where the temps are measured at (location)

Iat 1 where is that located?
Iat 2 where "
Iat 3 where "

I've noticed that 2 of the 3 sensors read the same I believe 2 and 3.

Thanks for the help Ted

Well it is complicated because a ZL-1 and an SS do not share the same operating systems or wiring.

In the case of a ZL-1 IAT-1 is in the MAF. IAT2 in in the TMAP sensor.

I am not aware of any IAT-3 on this platform, but it might be your ambient sensor in the grill area.

Keep in mind the data logging software uses generic addresses to log pids and sometimes they might be the same address even though they are labelled different.

There is however MAT or Manifold Air Temp, but it not a sensor, it is a calculation taking in to account Water Temp, Ambient Temp, IAT-1, IAT-2, Altitude, and humidity, there may be more but that is what I know of.

The problem with aftermarket superchargers is the sensors they might change and if calibration for those sensors is correct or not which will skew the MAT.

MAT is what is the top row of your IAT Timing adder or subtractor table.

What most don't understand is that burn rate is effected by MAT so if you don't remove timing as MAT goes up, you will move peak cylinder pressure too early in the crank rotation and lose power.

The ultimate goal is for peak cylinder pressure to occur around 15 Degrees after top dead center on the power stroke.

In the case of an SS model it only has IAT1 which is located in the MAF which is why we break out the wires from the maf and move the to either the TMAP or IAT2 sensor that come with aftermarket PD superchargers.

The SS still calculates MAT in the same manor less one input.

If supercharger and intercooler system where perfect your IAT-1 and IAT-2 in a ZL-1 system would be very close to the same like with in 10 degrees F regardless of length of pull.

If you are seeing a rise in temp over distance then the intercoolers are inadequate for the conditions.

You can expect about 11 degrees of air temp rise per 1 lb. of boost then it is up to the intercooler cores to remove that temp from the charge air.

So IAT-1 + boost X 11 - intercooler efficiency equals IAT-2

Obviously the lower the boost level the less the intercoolers have to work, there will always be a point when adding boost that you overwhelm the intercooler cores with heat then IAT will rise over distance.

AKA most of the factory superchargers when spinning them faster than designed.

As to the comment about Dyno fans vs on road, I believe I have one of the best dyno facilities in the country, My dyno fan can simulate 60 mph traveling speed so anything above that is still considered stationary.

As the car moves through the the air pressure increases exponentially so cooling increases with speed.

Ted.

[laynlo15]

I ran meth/water for 4 years and never had a failure plus I still have my Teeth.

[JANNETTYRACING]

Originally Posted by laynlo15

I ran meth/water for 4 years and never had a failure plus I still have my Teeth.

You won at the casino too LOL

[danhr]

Originally Posted by laynlo15

I ran meth/water for 4 years and never had a failure plus I still have my Teeth.

pics of said teeth

[EDFHOBBIES]

Originally Posted by JANNETTYRACING

Well it is complicated because a ZL-1 and an SS do not share the same operating systems or wiring.

In the case of a ZL-1 IAT-1 is in the MAF. IAT2 in in the TMAP sensor.

I am not aware of any IAT-3 on this platform, but it might be your ambient sensor in the grill area.

Keep in mind the data logging software uses generic addresses to log pids and sometimes they might be the same address even though they are labelled different.

There is however MAT or Manifold Air Temp, but it not a sensor, it is a calculation taking in to account Water Temp, Ambient Temp, IAT-1, IAT-2, Altitude, and humidity, there may be more but that is what I know of.

The problem with aftermarket superchargers is the sensors they might change and if calibration for those sensors is correct or not which will skew the MAT.

MAT is what is the top row of your IAT Timing adder or subtractor table.

What most don't understand is that burn rate is effected by MAT so if you don't remove timing as MAT goes up, you will move peak cylinder pressure too early in the crank rotation and lose power.

The ultimate goal is for peak cylinder pressure to occur around 15 Degrees after top dead center on the power stroke.

In the case of an SS model it only has IAT1 which is located in the MAF which is why we break out the wires from the maf and move the to either the TMAP or IAT2 sensor that come with aftermarket PD superchargers.

The SS still calculates MAT in the same manor less one input.

If supercharger and intercooler system where perfect your IAT-1 and IAT-2 in a ZL-1 system would be very close to the same like with in 10 degrees F regardless of length of pull.

If you are seeing a rise in temp over distance then the intercoolers are inadequate for the conditions.

You can expect about 11 degrees of air temp rise per 1 lb. of boost then it is up to the intercooler cores to remove that temp from the charge air.

So IAT-1 + boost X 11 - intercooler efficiency equals IAT-2

Obviously the lower the boost level the less the intercoolers have to work, there will always be a point when adding boost that you overwhelm the intercooler cores with heat then IAT will rise over distance.

AKA most of the factory superchargers when spinning them faster than designed.

As to the comment about Dyno fans vs on road, I believe I have one of the best dyno facilities in the country, My dyno fan can simulate 60 mph traveling speed so anything above that is still considered stationary.

As the car moves through the the air pressure increases exponentially so cooling increases with speed.

Ted.

Thanks for the info Ted, it is complicated.

But from your explanation both the Zl1 and SS read the IAT 1 from the MAF This is what gets me baffled I would think both should read the same air going into the motor should be more similar temps.

IAT 2 makes perfect sense to read differently a better blower more efficient brick I have a slightly larger reservoir the Tmap is located in a better position on the 2650.

[laynlo15]

Originally Posted by danhr

pics of said teeth

Haha for sure.

[LiqTenExp]

Originally Posted by EDFHOBBIES

Thanks for the info Ted, it is complicated.

But from your explanation both the Zl1 and SS read the IAT 1 from the MAF This is what gets me baffled I would think both should read the same air going into the motor should be more similar temps.

IAT 2 makes perfect sense to read differently a better blower more efficient brick I have a slightly larger reservoir the Tmap is located in a better position on the 2650.

For stock ZL1 the physical sensors are (I have manually pulled IAT1 and TMAP sensors and confirmed the mapping):

• IAT1 = MAF temp sensor
• IAT2 = N/A (value is IAT1+math)
• MAT = TMAP (Temperature and MAP) in rear of SC

In HP Tuners the mapping is confusing:

• IAT Sensor Cal = MAF temp sensor
• IAT 2 Sensor Cal = TMAP temp sensor (there is no MAT table, they should really fix this to remove the confusion)

MAT = PID 2128 (corrected)

My TVS2300 came with a harness to re-locate the T part of the TMAP into Cylinder #2 runner of the lower body of the blower. The TMAP sensor is susceptible to heat soak in the rear position. If MAT values are incorrect (high) you can pull timing unnecessarily via "IAT Adv" parameter per IAT table values (base/mult).

See picture below of the stock 4 bar TMAP sensor, you can see the thermal sensor in orange protruding out. You will also notice it is a 4 wire device as compared to a standard 3 wire MAP sensor, 4th wire is for temp out.

[EDFHOBBIES]

Originally Posted by LiqTenExp

For stock ZL1 the physical sensors are (I have manually pulled IAT1 and TMAP sensors and confirmed the mapping):

• IAT1 = MAF temp sensor
• IAT2 = N/A (value is IAT1+math)
• MAT = TMAP (Temperature and MAP) in rear of SC

In HP Tuners the mapping is confusing:

• IAT Sensor Cal = MAF temp sensor
• IAT 2 Sensor Cal = TMAP temp sensor (there is no MAT table, they should really fix this to remove the confusion)

MAT = PID 2737

My TVS2300 came with a harness to re-locate the T part of the TMAP into Cylinder #2 runner of the lower body of the blower. The TMAP sensor is susceptible to heat soak in the rear position. If MAT values are incorrect (high) you can pull timing unnecessarily via "IAT Adv" parameter per IAT table values (base/mult).

See picture below of the stock 4 bar TMAP sensor, you can see the thermal sensor in orange protruding out. You will also notice it is a 4 wire device as compared to a standard 3 wire MAP sensor, 4th wire is for temp out.

Thanks for the info..

So I have the Ibanks gauges literally can read everything that the OBDII reports.

If I want to know what the temp is post intercooler/Brick
What would I chose from the OBDII gauge for my camaro ss?

See pic..

Not sure why the gauge uses IAT 3 as it's not listed in pic.

[LiqTenExp]

MAT, third from bottom

[JANNETTYRACING]

Originally Posted by LiqTenExp

For stock ZL1 the physical sensors are (I have manually pulled IAT1 and TMAP sensors and confirmed the mapping):

• IAT1 = MAF temp sensor
• IAT2 = N/A (value is IAT1+math)
• MAT = TMAP (Temperature and MAP) in rear of SC

In HP Tuners the mapping is confusing:

• IAT Sensor Cal = MAF temp sensor
• IAT 2 Sensor Cal = TMAP temp sensor (there is no MAT table, they should really fix this to remove the confusion)

MAT = PID 2737

I am going to politely disagree with you here.

On the ZL-1

IAT1 is in the MAF
IAT2 is in the TMAP
MAT is a calculation as I mentioned above.

MAT refers to IAT table for timing adder or subtractor.

On the SS,

You only have IAT1, even if you move it to the blower.

MAT is a calculation taking in to account all the things I mentioned above.

MAT refers to IAT table for timing adder or subtractor.

Ted.