Ram air

[Akir-ra]

Can anyone explain what ram air is? Can it be used with an SU Carb system? I've been told that it is a form of allowing air into the engine thur an extra "port" on the hood. There is aram air for sale at he Georgia z Club and I'm wondering if its worht my time. Like will it increase hp?

Thanks in advance..

[2ManyZs]

A Ram Air system uses a hood scoop or just an extension of the air cleaner that gathers outside air and forces it into the intake.

It can work with the SU air cleaner if you extended it ahead of the radiator support to gather as much cool, outside air as possible. The premise is, the faster the car is traveling, the more air is being forced into the intake. It might increase hp a bit. How much depends on the engine itself and if the air is being taken from a high pressure area and being forced into the air cleaner.

It wouldn't hurt to try, just to see how much could be gained. Just take a length of tubing from ahead of the radiator support to the air cleaner, but you will need to remember to use a high flow air filter like a K&N or you will be trying to cram air through a filter that will restrict the air flow.

I think the Firebird and Camaro's with the Ram Air system typically are rated at 15-25hp more than without, of course they usually had other mods so the actual gain would likely be less. You would also need to address the exhaust at the same time, more air in needs a better way out.

[hmsports]

2Many has a great idea of getting a tube out in front of the radiator to get the coolest air to the carburators.

The next thing to keep in mind is that air will tend to find the path of least resistance. This is why most racers build shrouds that force all the air that comes in the grill through the radiator. These are made with thin sheet metal and all the gaps are filled so no air can get by without doing some cooling.

It would be a good idea to build a box that 2Many's duct would hook to. The box should have a large opening (say 12" tall by 6" wide) to gather as much air as possible and shrink it down (which will in effect compress the air and make it travel faster and be more dense -- ram-air) to the, most likely 3" hose, that fits nicely through the radiator support hole. This should extend as far forward as you can get to the grill.

And just like 2Many says, an engine is basically a big air pump - the more you force in, the more you need to get out - through a good quality header.

[2ManyZs]

Ram air was something everyone wanted to do in ITS years ago, so they wouldn't be using the hot underhood air. Too bad it's not a legal modification huh?:devious:

[hmsports]

As long as you don't extend the intake beyond the bodywork and make any new holes in the body or frame, you can get away with it. Always a way to push the limits :classic:

[V8-240Z]

Bryan Little's web page has Passive Ram Air setup using a 77-78

vented hood and a L6 that has carburetors that is interesting.

<a href="http://www.geocities.com/zgarage2001/air.html">Passive Ram Air</a>

[carguyinok]

I just got home from taking my hood over to my body guy. I will be posting photos soon. I am doing A true ram-air style hood with my stock hood. He is going to take and cut and roll two openings one on each side of the front rise in the hood. I told him I wanted to take pics of it in the diff. stages and he is more then fine with this. So soon there will be photos.

We are shooting for it to be done by sunday.

I know this wont work on the true Z motor set-up without some type of air intake molded in. But this will work fine for the air intake on my 350TPI.

I cant wait....

[Akir-ra]

Bryan Little's web page has Passive Ram Air setup using a 77-78

vented hood and a L6 that has carburetors that is interesting.

<a href="http://www.geocities.com/zgarage2001/air.html">Passive Ram Air</a>

This description of ram air was a big help..However i think that's more modification than I'm willing to do..so.. What about air horns...? Any improvemnets from those..? They seem to be the most vialbe solution..any ideas?

[hmsports]

The stock air cleaner assembly has built in air horns. I've seen aftermarket horns but they are very similar to the same size and shape - just more rounded all the way down. I don't know if you would notice any improvement - it is most likely one of those you could only measure on a high-dollar engine dyno.

This of course is just my opinion - I am no expert in air flow dynamics. I use two separate aftermarket air filters in which I have taken a stock backing plate and cut out the air horns and bolted them inside.

[2ManyZs]

Actually, from all I've read the air horns on the stock backing plate of the air cleaner flow as well as most any air horns. Perhaps an easy way to try it would be to use the stock air cleaner with a K&N filter in it. Then use light gauge tubing to run up to the radiator support where you already have a large round hole, then connect it to the stock air cleaner intake. Or take off the "snout" on the stock air cleaner and connect a larger one to the air cleaner housing and then plumb that into the tubing.

If you can find an extra air cleaner and a little bit of tubing and a piece of hose to connect them, it would be a cheap mod and might actually help increase the hp, maybe not enough to feel in the "seat-of-the-pants" but every little bit helps.

[Murph]

A few years ago one of my mates made a ram air setup for his 1st gen camry for a laugh. It collected air through a fibreglass scoop roughly 12" x 4" infront of the radiator. I'm not sure how different it felt to drive, but I know it increased the top speed from 160kph to about 175kph.

Unfortunatly it started overheating once he hit that speed due to lack of flow to the radiator.