Efficiency of the wheel drops dramatically when you get away from the design point. The lost efficiency is converted to heat.

 

Doesn't being below the low end of the curve imply very little work (little or no compressing) and so little or no heat into the air? Out of curiousity, I captured some numbers last fall with the crank belt removed and everything else as in sig. The engine pulled mid 220s gms/sec though the max MAP was .87. I would have thought MAP would be nearer 1.0, but still it seemed to say the PD internal bypass duct size allows enough reverse flow to supply most or all of the engine needs at low rpm. I don't know at what engine rpm the wheel provides enough flow to force some bypass flow back to it's inlet. I'd guess somewhere between 1500 and 2000.
(just a lab rat collecting data)

 

Not 100% sure but sounds like the 8 degree jump you saw is probably all heat from compression particularly since there is some sort of low rpm bypass. I found this web page which has some info on intercoolers for superchargers and has some discussion/numbers on compression heating (all new to me as have always done n/a) http://www.strokerengine.com/ProCharger.html

 

I'm sure it is compression heating. I think the most comp air heating I've recorded was 27°f (~370 gms/sec MAF). Some interesting charts at that site. Since my engine internals and heads are stock I'm limited as to the amount of boost I can tolerate. Of course a stock clutch and factory fuel pump are also limiting. The contortions of plumbing an intercooler don't seem to be worthwhile with such modest boost. Water/Methanol spray might be interesting but this is a daily driven street car whose engine only gets hammered for 3 to 5 seconds once in awhile. What I've done to it is mostly to enhance the midrange. I've altered PCM timing tables and a few other things to protect it.

 

We weren't criticizing your setup or suggesting an aftercooler. My point is that it's probably not reasonable to compare a blower setup to a normally aspirated cold air setup.

Its all just a numbers game. To do a complete analysis, someone would have to put both elbows on a flow bench and measure the pressure loss vs flow. You can't just look at the open area - flow is affected by the severity of the radius, the smoothness of the wall (corrugations vs smooth) the friction factor of the materials, etc. Then you get into the heat transfer and its even more complicated. You could reduce heat transfer by polishing the outside to a mirror finish, and/or adding cera-metallic coating.

I had a Callaway Honker CAI, and the equivalent of a 1LE elbow on my Formula when we built the stroker. The shop didn't like it, and was looking for a better way to hook things up, and spray the dry nitrous. They picked up a Vortech elbow, and decided that wasn't any better than the 1LE rubber elbow, even after they machined out the dividing wall. It ended up being a good excuse to switch to the Ram Air hood and box. But they wouldn't even let that alone. They cut the grid out of the top of the air box, and told me I better cut the baffles out of the hood. Then I added the Fernco coupling to get rid of the crappy bellows that SLP supplied for the MAF to TB connection.

 

"We weren't criticizing your setup or suggesting an aftercooler. My point is that it's probably not reasonable to compare a blower setup to a normally aspirated cold air setup."
No, No! I honestly didn't think anyone was. I was just trying to contribute what numbers, conditions, specs and speculation I had that might be relevant or useful to the discussion. BTW, FWIW the Trickflow elbow I use is the silver ceramic coated. Just tinkering around.

 

 

i know i'm late to the show...but i just put a trickflow elbow on my 93...fit perfect..and

i got my temp gun out and temps were surprisingly below or at 190*...i'm sure air temp is higher but this is the best i could provide..

 

The temp of what was below 190?

 

here are three thousand one trick flow elbow for sale, soon as I get a replacement 1Le

I have noticed in the past that Mine was extremely hot at the drag strip

 

i just shot the elbow...i'll do it again but i was trying to see what was wrong with the elbow hense i bought one???

not sure if by my fans being on 100% run time makes a difference,but i like testing and confirming..

 

the photos of the side by side, particularly the one showing the mismatch of the trickflow through the throttle body are reason enough to use the 1LE. No reason to add a restriction to the intake, particularly one with a cliff that creates a low pressure vortex right at the throttle inlets.

 

i still stand at the point of it is smoother air flow to the throttle body because that annoying resinator tube jetting down behind the radiator. i do believe that the air going through it will keep it cool thats just to my knowledge.

 

Asked and answered. The air picks up heat and cools the elbow. The heated air has a lower density, leading to lower power potential. If you don't believe, well, that's up to you...

 

I understand the principle of the air picking up the heat from the aluminum elbow. I still have a hard time believing that the air passing through gets heated up enough to impact performance.

Once the air passing through draws the excess heat out of the aluminum elbow, it does not pickup nearly as much heat because the heat isn't as abundant in the aluminum. And even though aluminum is an excellent conductor of heat, I don't see it transferring that much heat that fast. If it did, it would maintain a high temperature, as it would pull it in as fast as it could disperse it into the passing air. It cooling as it does seems like the air is pulling heat out of it faster than it can absorb it from the outside environment.

When compaired to the TB bypass, the air passing through cannot absorb and remove the heat out of the TB because the coolant is transferring it's heat. And transferring from a liquid to aluminum is much more efficient than tranferring air to aluminum.