Custom air box

[Evil One]

I have dealt with many different kinds of cars over the years.
One constant is that cars make more power with a larger charge of cooler, denser air.
My car came with a green cone filter sitting open in the engine compartment.
Great for sound but not so good for performance.
I had been looking at making a custom enclosure drawing air from where the stock airbox intake was and a couple of other places.
I am now on the list for the ToMyx intake, and plan to follow thru with the construction of my box.
It is not going to be a fully enclosed box, actually more of an elaborate shield forcing the engine to draw cooler air than what is available underhood.
I have dynoed cars with outside of the engine compartment filters and underhood filter enclosures, there have been 1-2 hp variance in the runs..
For me, this is chalked up to standard variance in dyno runs.
Many people worry about hydrolocking the engine with a remote mounted filter, using an enclosure pretty much quells that worry.

I was just wondering if anyone on SVXWN has built one of these and what their experience with it was.


Jim

[ensteele]

I have seen several. You might use the search and see if you can find the threads about them. Good luck.

[nextse7en]

Subaru designed the intake to be provided with pressurized air from the "wake effect" essentially, air splits when it meets the radiator, and crams into the hollow where the intake resonator lives. I don't think you are going to find colder air, or a much more effective way to create pressure in the upper intake.

If you wanted - you may find it possible to chill the exterior of the stock airbox by scooping pressurized air into some sort of heat sheild surrounding the box.

That being said, I think you would be looking at miniscule power gains, if any. The airbox is already kept cooler than the amient temps in the engine bay, because it constantly has air flowing thru it from the outside.


I would instead focus on smoothing out the intake flow from a stock box to the throttle body. Or, barring that, design a ram air duct. Ram air has been shown to add a few ponies at high speeds.

In closing, I would say that a stock airbox, with a mild ram effect, a tomynx intake - properly shielded, and phenolic spacers from outlaw would provide an optimal intake for a stock engine.
-Patrick

[Evil One]

I got my car without the stock airbox


Jim

[Trevor]

Thanks Patrick,

A breath of fresh air (pun intended!), after all the BS that has been on offer of late regarding intake systems.

Good on you, Trevor.

[SVXRide]

Originally Posted by FOMOGO

I got my car without the stock airbox


Jim

Jim,
Check my locker....I've been running a true ram air set up for over 2 years...calculations based on the pressure readings I took when I first installed it indicate ~5-10 hp improvement once you get over ~30mph.
-Bill

[Trevor]

Something which appears to be missed in discussions regarding intakes, is that the OEM system incorporates a plenum immediately before the throttle bodies and this fixes the start of a carefully designed variable system. Eliminating this plenum is surely not desirable.

[Myxalplyx]

Originally Posted by FOMOGO

I had been looking at making a custom enclosure drawing air from where the stock airbox intake was and a couple of other places.......
It is not going to be a fully enclosed box, actually more of an elaborate shield forcing the engine to draw cooler air than what is available underhood........
I was just wondering if anyone on SVXWN has built one of these and what their experience with it was.

Jim

SilverSpear
http://www.subaru-svx.net/forum/show...=intake+copper

[Evil One]

Yea, I read the thread about the copper box.


Jim