Early numbers from my (extended) drive to work today.

Conditions: 70mph 6th gear (approx 3k rpm) uninterupted freeway driving for miles
Ambient: 40
Inlet: 200
Outlet: 60
TE: 88%

I will establish a protocol and gather more -scientific- data, but the ratios above were quite steady (the gauge shows some variation, but the variance is extremely small--it seems very sensitive)

A few "first impressions":
1. IAT gauges might cause accidents...
2. Temperatures out of the supercharger are scary (200+)
3. Intercoolers are amazing
4. Heat soak is a real problem. In stop-start traffic, and after a short stop for a coffee, the IATs rise 20-40deg very quickly.
5. The DFIC is very good at lowering temps from a stop.
6. Temperatures rise very rapidly when running WOT.
7. These VR probes are very sensitive and fast.

More to come, cheers.

 

Where was the inlet temp probe located.
That is a very did I say very high inlet temp if you took the reading at the boot under those conditions.

From memory I never saw temps that high on an 80º+ day.
Not until I did a hill climb.

 

The probes are located exactly in the center of the inlet and outlets of the DFIC--like Sid I drilled holes underneath the IC and installed the probes so that they sit in the airstream--they couldn't be more centrally located.
The 200deg temps were the highest I read - give or take 5 deg. Tooling in traffic they fell to about 160-180.

I'll post a photo of the temp probe location.

 

THat is really wierd... I looked at my IAT on the Flux for two weeks and I never saw anything like this..... I wonder why

 

I saw Sid's location so they should be decent.
Curious though, didn't Sid post in a thread about very high inlet temps due to the VGS?
How well are those probes thermally isolated? Your outlet temps are higher compared to ambient than mine run if, a big if, your temps were taking at cruise. I always did mine when temps stabilized for 10 seconds.

I would really like to see this duplicated with your vampire tap plugged up so all the air is forced through the IC.

Very cool stuff.

 

Here's the location of the probes;

The inlet is located similarly.
Other observations: This morning the probes read identically at 20deg above ambient. If there is an error in the calibration of the gauge it's constant across probes (in the gauge not the probes) and it would make the TE higher than I reported. In fact, if it is +20 then what I measured this morning is 100% TE.
cheers,

 

It *could* be the VGS - I have both VGS and Ryefix BPV. I can remove the VGS (although my wife is suspecting something everytime I go out to get something from the garage fridge and it takes an hour...)

 

It IS the VGS...I experienced/reported the same findings when I had it installed but not many people heeded my warnings...if you get on it with the VGS mod, the pre-temp will shoot over 250F!!!

 

Thanks for posting, DrPhil.
I would like to see the numbers without the VGS.

Just level with your wife and tell her you are conducting research that will benefit an entire community.

 

Phil...are you saying that with the motor cold/off, the gauge read 20F higher than ambient? Thats not right...

 

I presume that after a night sitting in the garage, the inside of the IC should be at ambient? I will check again tomorrow morning with a more accurate thermometer for ambient. Cant do it until then as Im at work and the car is hot.
I had a pretty bad flat spot problem, hence the VGS. However, if it's responsible for those IATs then I'll live without it I guess.
Sid: I read your original VGS-IAT posts and recall there was never any replication. Once I undo the VGS, and if the temps fall, I will be first to award you the "a guy before his time" award! I don't think people doubted you, they just couldn't believe it (now that's a sentence worth thinking about.)
Curiouser, and curiouser...

 

with the Flux I routinely saw the IAT 20 deg above ambient FWIW... temps rise at idle and quickly lower when you start to move

 

Phil...I did report that I've experienced the same results on two seperate occasions when I tried and then retried the VGS...my suspision is that the VGS mod is causing BPV to shut prematurely prior to boost conditions thereby causing the SC to pump unecessarily, creating losses evident by the heat generated. The other time this happened was when my BPV was stuck shut because of gum deposits...

I suspect that your pre-IC temp will drop into the mid to low 100F once you remove the VGS...sides, you already have the DTBPV to solve the flat spot condition...

If the temps doesn't drop as I predict...it may be also due to the DT valve as it effectively shuts the valve earlier through it's stronger diaphram spring...the only way to find out is to take readings from a none VGS and/or DT modification (besides my reading)...

Here are my finding:

-During daylight driving at steady highway cruise for extended periods (70-80mph), IAT is within 15-20F of ambient...
-Evening cruise under same conditions, IAT is within 5-10F of ambient...I suspect that sun heat load makes that much difference...
-WOT conditions, IAT is 5-10F BELOW Ambient...caveat...this is primarily due to my water/meth injection taking place...

 

Not if they're both off 20º and don't you get me started on that 100% efficiency thing again

Great location but is that metal on metal clamping? If it is you have created a nice heat sink.

BTW I'm not poking at it I'm just trying to figure out why your temps are different than mine. Not to say that mine are perfect either.

 

Pop the hood a little in the garage, to be sure it's cooled down.

 

Ah yes, here's where we agree to disagree

I run the VGS and see much lower conditions.
I do only run a 15% pulley and didn't think about that until just now.
What are you running Sid?

 

VGS ???

Sorry for the ignorance!

 

Good point.
I have noticed that with the hood closed my probe temps were a consistent ~10º warmer than ambient even after an overnight sit outside.

I have no garage

 

My combination is 15% + 2% crank

 

Read on MacDuff
https://www.northamericanmotoring.co...ghlight=vacuum

 

No worries about the 100%. I was simply doing math. My reported calculations give TE = (200-60)/(200-40) where the 40 is ambient, not measured by the probes. If the probes read the same (which they do at cold/start) but the guage reads +20 then the TE = (180-40)/(180-40) which is a ratio of 1.0. Of course, until I discover what's going on, I'll not stand by any of the math.
btw, the probe is mounted with rubber O rings and silicone, and is made of SS. When I go to my car at lunch time, I'll check the temps (I installed them with a constant 12v power supply and an 0/1 switch so I can read temps even with the ignition off.)

 

May be a very valid point.

Something seems off for when I did my GTT IC testing the probes went into the rubber boots. I live in florida and never saw 200 temps - at best I saw 160 degree temps after numerous back to back G-Tech pulls.

 

I revisited the original DFIC thread when the first temperature numbers were posted. The core-in temps were 182degF. Someone posted some numbers from Randy Webb and he reported core-in temps of 260degF! Could it be the altitude (5000+ here in Albuquerque)?

 

The DT bypass valve increased my IAT (measured using the OEM sensor via the OBDII port) by roughly 10F during steady-state highway cruising around 75mph, give or take a few degrees, and all else being as relatively equal as practical. The above figure is a ballpark average from watching the IAT and ambient temps during several weeks of commuting to work.

One other comment about some of the IAt numbers; I strongly suspect that air temps measured via t-couples right at the exit of the intercooler will be somewhat lower than those measured in the intake manifold (as I did). If you are comparing between cars, I think the post-intercooler measurement needs to be taken in the same location.

Scott
90SM

 

I'll have a DFIC here next week, and hopefully will be able to post some numbers.