[Atomic Ed]

Been playing around with different ideas on reducing IATs. I first would like to get a sense of what the Maggie is doing on our cars verses the E-Forces out there. Not wanting to start a "mines better than yours" discussion, but just gather some un-biased info to possibly start a discussion thread on heat management.

My E-Force IATs tend to run around 100-125* F when cursing in 85* ambient. Hard pulls at the same ambient will push the IATS up to 150* F, and then up to roughly 160* after three hard pulls.

How does your Maggie on your Gen 6 compare?

[toohighpsi]

This plot shows 30 minutes of cruising with the Magnuson SC as I drove my son to school in the morning on 101 in CA. There were some times of 65-75 MPH and of course some times in traffic at a dead stop (it is CA after all ). Inlet air temps run between 0-15 degrees F delta from ambient. Ambient is the white line, IAT is the yellow. Not surprisingly, IAT are closer to ambient temp at higher vehicle speeds.

[toohighpsi]

This plot shows the most extreme IAT that I can find with the Magnuson so far, a 10.8 second quarter mile pass. This is running a smaller 90mm pulley (stock is 98mm) which is delivering 158kpa or ~8.5psi of boost (stock~6.5psi) on a 100 degree F ambient temperature day. I apologize for all of the extra plots but the one you are looking for is on the top. Once again - white line is the ambient temp of the air and yellow is the IAT. At the end of the 1/4 mile, just as I lifted, the IAT reached a peak of 140F for a delta of 40 degrees F over ambient.

Hope this helps!

[E-Ray]

You would think the manufactures would release this kind of information. I don't think I have ever seen actual IATs advertised on either kit. thanks for info guys.

[Daves1SS]

Very good information to see. I hate to see that the Edelbrock IAT's are consistently 20-30 degrees higher than those on a heartbeat system though. :(

[Atomic Ed]

Thank Toohighpsi! Just what I was looking for.

Would you happen to know where the Maggie IAT sensor is located on the SC? On the E-force, it's installed in the manifold adapter, about an inch from the top of the head with full metal-to-metal contact between the head and the adaptor. IR readings near that point are around 210-220* F at idle. I also know that the IAT sensor on my E-force is reading accurately. So one theory is that there is a somewhat higher reading due to the near contact of the IAT (TMAP) sensor with the head.

Regardless, it looks like the Maggie does run around 20-30* F cooler IATs. I've several ideas on how to tackle the higher IATs and the information on the Maggie gives me a working target. First step is to have a heart-to-heart (pun intended) with the Edelbrock folks.

[yonson]

Just an FYI, when I asked the engineers at Edelbrock about their IAT's being higher they stated that they purposely put their TMAP in the hottest location they could find to ensure that their spark calibration is correct at WOT under the most extreme conditions... Everyone knows their calibrations are quite conservative anyway, so it makes sense.

I don't believe it was on the Maggies, but at one time there was at least one supercharger manufacturer that was using an incorrect IAT transfer function and they were reading lower than actual by 12 - 14 degrees C.

[Atomic Ed]

Originally Posted by yonson

Just an FYI, when I asked the engineers at Edelbrock about their IAT's being higher they stated that they purposely put their TMAP in the hottest location they could find to ensure that their spark calibration is correct at WOT under the most extreme conditions... Everyone knows their calibrations are quite conservative anyway, so it makes sense.

I don't believe it was on the Maggies, but at one time there was at least one supercharger manufacturer that was using an incorrect IAT transfer function and they were reading lower than actual by 12 - 14 degrees C.

Thanks for the info on Edelbrock's thinking. But I do still wonder if the IAT sensor temp reading is a combination of both the actual inlet air temp as well as some added radiant heat due to the near direct contact of the sensor with the head. I'm thinking a first cut at working on the IATs will be a thermal insulator gasket between the heads and the manifolds. I don't expect a lot from this, but hey, it's worth a shot and its a simple, passive mod.

I do know that the TMAP sensor on my car is dead on. I cross checked both the PID and the OBD readout against the coolant temp, ambient temp and IR readings with the engine stone cold and they were all within 1* F of each other.

[yonson]

Yeah, unfortunately due to the placement of the TMAP they are more susceptible to heat soak.

[TrekGTO]

Originally Posted by Atomic Ed

Thanks for the info on Edelbrock's thinking. But I do still wonder if the IAT sensor temp reading is a combination of both the actual inlet air temp as well as some added radiant heat due to the near direct contact of the sensor with the head. I'm thinking a first cut at working on the IATs will be a thermal insulator gasket between the heads and the manifolds. I don't expect a lot from this, but hey, it's worth a shot and its a simple, passive mod.

I have no experience with the LT1 or the new Edelbrock's for it but I have several LS3 customers only use the TMAP for MAP and relocate the IAT by using GM compatible sensor with GM scaling in tune. This resulted in much lower real temperatures since the TMAP was boxed in and reading housing. I know you have to be especially careful fooling with IAT, you dont want to make changes if you are using a canned tune.

I would check Intercooler coolant temperature against IAT in real time. I always watch coolant temperature a display is included with the Chiller kit. The AU SS I'm working on now has a flow gauge and 2 temp displays. That's another thing, you have to have all the air out of system the flow gauge picks up air in system great! I had not seen these displays and think I will add them as an upgrade to my old faithful.

Koso Thermometer

[ADM PERFORMANCE]

Originally Posted by Daves1SS

Very good information to see. I hate to see that the Edelbrock IAT's are consistently 20-30 degrees higher than those on a heartbeat system though. :(

That's been "KNOWN FOR YEARS ",Its to bad it not more public.

I will see if we can get supercharger IATS a stick here under forced induction.

[Atomic Ed]

Originally Posted by ADM PERFORMANCE

That's been "KNOWN FOR YEARS ",Its to bad it not more public.

I will see if we can get supercharger IATS a stick here under forced induction.

I was thinking the same thing. Something like "IAT management".

[toohighpsi]

Originally Posted by yonson

Just an FYI, when I asked the engineers at Edelbrock about their IAT's being higher they stated that they purposely put their TMAP in the hottest location they could find to ensure that their spark calibration is correct at WOT under the most extreme conditions...

The IAT sensor on the Maggie is in the base of the manifold between cyl #2 and #4, with the same reasoning as stated above - #2 is normally the warmest of the intake ports. Cylinder to cylinder temp spread on the Maggie is pretty small, normally less than 10 degrees F during a dyno pull.

[LesBaer]

I haven't been keeping up with the board all that much nor have I read through everything in this thread, but I came across this thread and someone had PM'd me asking about my IAT's so I thought I'd share this. This is on Magnuson's site, under the gen6 Heartbeat: http://www.magnacharger.com/

"...Inside of the supercharger manifold, a large charge air coolers keeps your Intake Air Temperatures in check and provides consistent and repeatable performance. Combine that with the front-mounted low temperature radiator, electric water pump, coolant reservoir and you have a supercharger system with IATs that are typically only 20-40 degrees (Fahrenheit) over the ambient temperature. Maximizing your efficiency during cruising is the job of the supercharger’s integrated bypass valve. This vacuum operated system allows air to bypass the supercharger and the rotors to “free-spin" under light engine loads. During this situation the parasitic loss of the supercharger system is essentially negated taking less than one-third of a horsepower to turn the rotors. This bypass valve also allows your supercharged Camaro SS to maintain stock-like drivability and fuel economy - giving you a package that delivers power without compromise...."