Well that shorter intake fits but not well and it won't do the turn towards the throttle body for alminum radiators. I made another design that should work.

Black ABS with acetone vapor polish looks pretty sweet:


Also, I now have an extremely large collection of elbows and bits of plastic crap.

 

Just curious... how would you attach the filter? With great difficulty I'd imagine.

And would it stay dry when it's wet out?

 

I haven't had any issues driving in the rain so far- the filter is fairly high up. If you happen to have the plastic undertray off of the car it is very easy to get the filter on. I have put it on and removed it probably a dozen times now and if I don't have the tray off I just make sure I get the car up a little higher so the angle is better.

Also, attach the filter to the duct before attaching the duct to anything else. Also, don't press down on the duct too hard to avoid cracking it. Some amount of gentle pressure and twisting back and forth works best. On the newest couple of designs I made the fit not quite as tight so slipping it on takes less effort.

 

I have a megasquirt installed so I can log IAT and compare to ambient. Yesterday I went for a 30 minute drive on a 35mph commercial road with lots of stop lights in 93 degree weather. I saw a peak IAT of 106 degrees. I think I am getting some heat soak in my sensor since higher RPMs are cooling my intake temp. Here is how I have it mounted:


Does anyone have a an opinion on this being radiant heat from the radiator end tank and engine block vs heat being conducted through the heater hoses? The silicone elbows ought to insulate the aluminum section from conduction- right? I want to try some kind of heat shielding around the short section of crossover tube and see if it helps. Also, I think IATs will be better on cars with metal style radiators where the intake duct isn't making any direct contact with the end tank.

A 13 degree delta from ambient to intake in 93 degree weather seems pretty good to me

 

well, you do have your AIT sensor mounted in metal just above something that's radiating temps over 190°F and blowing hot air on it...

but i have a feeling the temps are accurate; it's still hot in front of the rad.

 

The air in front of the radiator doesn't get as hot as you would think. I tested it for 20 minutes at idle with the car parked (until a pattern stabilized) and the results were:
Ambient Temp 82F
Air 4 inches in front of radiator stabilized at between 92F and 97F depending on if the fan was running. At any kind of speed there will be no convection and the air entering the filter ought to be very close to ambient. I am making a small aluminum heat shield to block any radiant heat but I am guessing that radiant heat is only a small contributor at the filter tip.

The sensor is heat soaking though. My IAT climbed up to 117 degrees with the car parked over this 20 minute period. Some of that is going to be heat soak into the actual intake air but I think it is mostly the sensor.

 

If you upload or send me a STEP or Parasolid file I'll run a quick CFD on it.

 

well, replace the pipe with a straight one, and move the current just behind the filter.

 

The model is all polygons in 3dsmax so getting it into your software is going to be a pain. These are my export options:

I am going to try that but getting a bung into ABS plastic is going to be difficult. I have supplies for a carbon version coming and I will be able to epoxy in a bung down there.


Also, if anyone in the RDU area wants one, I have a pile of different versions of this duct.

 

Wow, I thought STEP was pretty universal.

Try IGS amd WRL. I should be able to work with one of those.

 

Depending on what you're using to mesh and STL would work too since and stl is basically just a surface mesh already.

 

I'm using Solidworks. I can open the STL file fine but it does not allow me to modify the part. I need to add lids to the part to enclose the passageway to run CFD and set the boundary conditions.

 

I don't know squat about solidworks but I am guessing it won't care what object format it is brought in as and will apply that limitation to any polygon model.

 

No, if you bring something in as a surface model its normally hosed, it needs to be a solid or parametric.

 

I have some $$$ foil from pegasus racing coming. 50/50 chance it does anything useful.

 

I just exported a file as an IGS and imported back in with the ability to modify the part. I am unable to do this when I export STL.

If you would like to see flow analysis of your part and visually see where it's chocked and possibly iterate the design for a better product I can help you out if you upload your part as an IGS. If not it's cool.

Good work on this project by the way. I'm considering 3D printing some ducting for my car eventually


EDIT: Just got the PM, will post back results in a bit

 

I PM'd you an IGS file though I can't tell if the export was successful. The 3dsmax plugin to load IGS getting pissed about the 27mb file size.

 

Solidworks crashes at the very end of the loading process. Not sure if its a bad file or my computer can't process a file of that size.

 

I can see if my i7 workstation at work can handle it if you want.

 

If you can somehow convert it to a step or parasolid easily that would be great. I'm kinda curious to see how this flows myself.