results of ram-air v1

[mbtoloczko]

I'm slowly working my way up to a ram-air system with the inlet duct cut into the bumper ala SVXRide. I have a hard time cutting into a perfectly good bumper, so I wanted to make sure it was worth it. As a proof of concept, I rigged up a ram-air system with the inlet below the front bumper. Pics are below. My butt dyno impression is that this setup works quite well, especially at low throttle where some pressure can build up in the inlet tract. For around town-driving, torque at 2000-3000 rpm feels much greater. Using my manometer, I have measured a positive pressure in the intake track at speeds as low as 40 mph. Prior to the ram-air, it was always a negative pressure at any speed. I did a few Mr. Dyno runs over the weekend, and there is a consistent improvement in TQ and HP across the powerband. Result is shown below.

[SVXRide]

Mychailo,
Okay, now you're really making me want to get to the dyno ASAP!
-Bill

[sicksubie]

Question: This may have been covered in another thread but I couldn't find it anywhere. I have a fiberglass hood witha hood scoop. What about doing a ram air intake straight from the hood scoop back to the throttle bodies? I only drive it in good weather anyway so rain wouldn't be an issue. Any thoughts or comments?

[NikFu S.]

Originally Posted by sicksubie

Question: This may have been covered in another thread but I couldn't find it anywhere. I have a fiberglass hood witha hood scoop. What about doing a ram air intake straight from the hood scoop back to the throttle bodies? I only drive it in good weather anyway so rain wouldn't be an issue. Any thoughts or comments?

Is the scoop right above the manifold? You'd have to relocate the maf behind it somehow. If you didn't you'd have a mess of tubing with extreme bends and heating from the engine.

[sicksubie]

I would still incorporate my MAF or maybe depending on the money a Z32 MAF and a stage 2 v5.

[sicksubie]

it is directly above it and I would probably attatch the MAF almost directly to the throttle body. Or at least as close to it as possible. With the measurments I've taken and the sketches I've done the bends would not create a problem at all.

[NikFu S.]

Originally Posted by sicksubie

I would still incorporate my MAF or maybe depending on the money a Z32 MAF and a stage 2 v5.

Right but in order to use air from the scoop for combustion effectively, you'll need a very short travel distance (ie true ram air) meaning you'll need the maf near the throttle body (rewiring hurdle).
Given the tiny amount of space the SVX hood leaves over the manifold (where the scoop sits) I imagine it would be very difficult to fashion an inlet that not only has soft bends and a large flowpath, but absorbs little heat from the manifold.

Anyone up for mspaint concept sketching? I'll give it a shot.

[sicksubie]

Here is a rough side view of what I was thinking about. Sorry about the roughness. I just did it in the last 5 min.

[sicksubie]

yeah scratch mine. I like the previous idea better

[svxsubaru1]

I really like your set up mbtoloczko, and those results seem great but I wonder if there is any sever areo damage done by having a duct open there?

For the other setup, could having the MAF that close to the throttle bodies casue erratic readings because of backward air pulses?

[Myxalplyx]

Good info mbtoloczko! I remember reading about the use of a manometer in this article:
http://autospeed.drive.com.au/cms/A_0629/article.html
'Eliminating Negative Boost'. The whole article isn't up on the net anymore. You have to pay for it. It was all about the use of that gauge. It was really insightful and I never forgot what I learned from it.

[sicksubie]

yeah, don't even consider mine now. I'm thinking about trying to put NikFu's into action. What about AFR's??? What about using the stock MAF???

[sicksubie]

btw sxvsubaru1, I'm rooting for the seahawks too. At least since the pats got eliminated... Shawn Alexander, Super Bowl MVP

[NikFu S.]

Originally Posted by sicksubie

yeah, don't even consider mine now. I'm thinking about trying to put NikFu's into action. What about AFR's??? What about using the stock MAF???

There's no way to fit a filter in my drawing there unless it's inside teh scoop, maybe jutting out a bit.

My personal set up is pretty much identicle to mbtoloczko's figure 1 but instead of poking out the plasting thing it reaches inside the bumper to the lower opening in the front. figure 2

[Myxalplyx]

Another good device to use that they mention in that article I talked about is called a 'Dwyer Magnehelic Differential Pressure Gauge'.