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Svenerachi1
01-16-2006, 05:52 PM
So i read the article regarding temperature readings under the hood.

I have a 99 Legacy GT first off, so any of my design ideas are for this application.

Now if i read this correctly, the temperature right behind the headlights was the lowest of anywhere under the hood. So first off, Here's to the Subaru Engineers for a good idea.... so how do we improve on it?

I'm assuming that an adaptation to the snorkus could be designed to take advantage of this.

I was thinking taking a clothes dryer air ducting and running it from a widened hole in the stock airbox through the fender and into the re-entry hole up to the headlights.

That, OR just cut a new hole in the stock airbox on the front side, plug up the original hole going into the fender and run a pipe, or air ducting depending on your willingness to spend money, up to the front of the engine bay to cut down on curves/ restrictions on the intake.

I thought this was a good way to improve on the frankenstein hodgepodge ebay intake idea where you just replace the stock plastic tube with an aluminum intake pipe mated to the stock intake air filter box.

So basically this is what i was thinking, have an aluminum pipe running from the throttle body assembly to the stock air filter box, then another aluminum pipe, 3 inch diameter running from a NEW hole cut into the front of the air filter box to a spot right behind the left front headlight, where according to the themocoupler post link (i saw somehwere, couldn't find it again when i tried looking for it) the coldest air temperature's were measured.



Throughout this rant i do have a question though. Just how much extra power do you achieve from having a CAI? I remember somebody did a great post on the compression ratio post regarding the gasket sizes, so if anybody has a nifty equation laying around that can answer my question, I'd love to see it.

ooberdoob
01-16-2006, 10:22 PM
you make many great points, so i really don't wanna do this, but...








with the snorkusectomy the airbox draws from the fender, doesn't get colder than the wheel well, and the gains are dyno proven 10hp on an EJ22.

valient effort, you get a cookie for one of the non-n00b style posts about already vocered items.

i'm not being sarcastic either.

Plays_with_Toys
01-17-2006, 12:02 PM
You get HP gains not only because of the colder air that the intakes provide, but because their larger cross sectional area (more area across the face of the pipe = more flow) and because of their smoother bends.

I am pretty sure that article specified the fender as coldest, or if a hood plug was removed from the RS hoods, that the under hood temperature dropped significantally to the point close to the fender temperatures. I could be wrong though.

Svenerachi1
01-17-2006, 04:14 PM
ok, yeah i just found the article i was refering to, and yes i was wrong to a certain extent. Big surprise there. anyway, i'm not sure what this spike in the temperatures across almost the entire field of tested areas after the car was parked, I downloaded a previous version of the graph without the legend built into the picture, oh well.

but anyway, to adapt my design, perhaps just bore out the hole that goes from the airbox into the fender to about 3 inches and to a 90 degree elbow into the fender to draw cooler air from the front of the fender, or would this be another unneeded restriction?

another question, any way to take advantage of the hoodscoop? I love having it look mean as hell, but i hate the fact that its non-functional. I realize that i could open it up and after covering wires and sealing everything really well that it probably wouldn't harm anything (water on exposed wires), but would lowering the engine bay temperatures help in any way? perhaps make it easier on the cooling system but that's all that I can think of.

oh and here's the link to that thread i've been refering to:
http://www.scoobymods.com/forums/showth ... readid=164 (http://www.scoobymods.com/forums/showthread.php?s=&threadid=164)

Svenerachi1
01-24-2006, 10:59 AM
okay, new question.

Why did the temperature at the end of the graph jump so high in the fender?

Wiscon_Mark
01-24-2006, 10:45 PM
good, valid, questions, rallitek makes a snorkus delete pipe for that application already, it goes from the airbox to right behind the headlight (looks stock).