Cold Air Box

[Matt49]

Has anyone use the one that Dominator makes (DOM-570)? It looks like it should work with an existing aluminum base and is somewhat "universal" but I am always skeptical of one-size-fits-all.
I started to make my own last year and never got it the way I wanted it. Thinking I might give this one a shot.

[grt74]

i know this, a cold air box will keep a ton of dust from getting in the air filter,i wasn't a big believer until i got a chance to see a filter off of my friends car after 2 races,huge difference,i guess the fan pulls a bunch of air towards the filter???but its a night and day difference,well worth the effort(your engine will love it)

[grt74]

but to the post i build my own and use form strips for seals

[let-r-eat]

Coat the bottom of that air box with ceramic heat resistant coating for best results.

[Dirtmod13]

Also read about high and low pressure areas to draw air from. NASCAR has some good air boxes and you know they researched and engineered it.

[Matt49]

Also read about high and low pressure areas to draw air from. NASCAR has some good air boxes and you know they researched and engineered it.

Wish I could find a picture of it but the best designed cold air box I've ever seen on a late model was on one of Billy Moyer's cars. He had a 4" drop deck at the time as many did and still do. With the straight 4" drop right at the back of the hood/frond deck bar. Then the bottom of the cold air box was flush with the the deck and ran completely level all the way to a point on the hood well in front of the breather, obviously below where the hood starts to bend down onto the nose. I want to say it actually laid right on top of the radiator. Then it wedged back and was sealed up really nice against the contour of the hood. Then the hood had about four 2-inch holes with screens just ahead of where the hood bends down (an obvious HIGH pressure area). And then there were holes in the 4" vertical drop behind the hood (an obvious LOW pressure area). I remember seeing that, studying it for about 30 seconds, and thinking, "now THAT makes sense."
This is similar to what I tried to build but I never could get it right. I'm decent on a lathe and milling machine but have zero patience for sheet metal :-)

[mod88s]

On my car, the breather is still under the cold air box about 1/4" and is not sealed off. Is there a way to completely seal it off around the carb? And is it very important to get the breather all the way up past the bottom of the box?

[Bubstr]

I heard from a friend that was on a crew in NASCAR, that with proper cold air box and radiator ducting, you could get over 450 lbs of down force on the front. The area at the front of the tires acts like a venturi. If you seal the hood behind the round down and duct radiator air it eliminates access to low pressure air, creating a low pressure area under the hood. This is with out Elephant ear fenders. Makes you wonder, what you could get.

[Kromulous]

What about making the cold air box apart of the hood, basically making a channel thru the middle, with a hole where the air filter housing is. Then take a slightly larger, round, piece and attach it to the air filter housing, making about a 1 or 2" ledge all the way around the outside, add some bead rolls to make it still, then a seal on the top side of it. When you put the hood on, the cold air box sits against that seal.

You can make the channel / air box open in the front, and in back or not.

[lindsey97]

FYI, the rubber door seal from a wrecked pickup works good around the top to seal it to the hood. And also around the hole where the spacer between the carb and filter base comes from through the bottom of the cold air box.

[dirty bert]

What about making the cold air box apart of the hood, basically making a channel thru the middle, with a hole where the air filter housing is. Then take a slightly larger, round, piece and attach it to the air filter housing, making about a 1 or 2" ledge all the way around the outside, add some bead rolls to make it still, then a seal on the top side of it. When you put the hood on, the cold air box sits against that seal.You can make the channel / air box open in the front, and in back or not.

Back in early 90s I think Clint Smith had a hood like that

[Krooser]

Why not use a real hood scoop that has the opening facing forward. I realized that it would be a dirt magnet but wouldn't it allow air to come into the air cleaner under pressure?

I could never understand how an air deflector can be called a hood scoop...

[Matt49]

Why not use a real hood scoop that has the opening facing forward. I realized that it would be a dirt magnet but wouldn't it allow air to come into the air cleaner under pressure?

I could never understand how an air deflector can be called a hood scoop...

All the air you're "scooping" would be disruptive to the air going over the midsection of the car...which is what ultimately makes it to the spoiler. In published wind tunnel testing of dirt late models, the breather itself was found to be a killer of down-force. Hence the piece you see on most cars these days.

[zeroracing]

I don't remember the numbers off hand but to create a true ram air effect like an airplane does it takes going much faster than we do to be able to compress the air into the motor.

[rakracing]

was explained to me once, drive down the road 50mph , stick head out the window facing forward and try to breathe then look backwards and breathe air is much easier to breathe facing back. if a air filter sticking out the hood was a good thing, indy cars and nascar wouldn't spend a fortune on air box tech