There is a kit available to make your FGF a Ram Air as far as the air intake is concerned. Metal pan...foam gasket...open hood scoops...the works. Its expensive but, how much hp will this really add vs. the stock snorkel air filter?

20 to 30 tq more...

in a 350 - 400 hp car..

and about 20 hp I'd say...

Anyone ??

Based on the chatter I have heard, it adds about 0% because the induction area on the hood is negative air pressure while the car is moving, meaing that the air cannot "ram" into the engine.

Even so, the cold air induction has to offer some gain, and the sound that the air rushing in makes is impressive enough that I'd be willing to spring for the money if couple of thousand bucks was just another little ol' check out of the checkbook.

Even if the induction area were in a positive pressure region you'd have to be going really bloody fast to get any significant pressure rise. Assuming 100% pressure recovery you'd have to be going 231 MPH to get 1 psi ram pressure.

It's not a "ram effect" that adds power. The important factor is the carb getting a supply of much cooler outside air than the hot air under the hood. Cooler air is denser.

well you know all a motor is a air pump the faster you get air in then out the faster your going to go along with fuel and spark i just bought a ram air kit from warpath resto. parts carb pan cover, carb pan, hood pan, air filter,vent tube filter, and the two foam seals and wing nut to hold it all together for 600.0 and its all steel and it all nice fitting and it looks awsome sitting on the motor i think its worth the money

The prices on the 7's and 8's are lower. The 9 is a different puppy: Look at the price just for the pans--over $500 each.

If you're just after the performance, why not make your own? At one point I was planning to use a GTO dual snorkel and run hoses up into the grill, similar to the Olds W30 style. I read somewhere that the W30 style, with hoses going straight to the grill was the best design. Then, you don't have to get all that expensive fabrication for your hood and aircleaner. The trick though, is to find space around that big radiator. I think also, to get the optimum performance, you'll have to rejet the carb.

I've also heard that hood-mounted ramair can have negative air pressure at certain speeds- especially the early 70s Formula Firebirds.

the one thing you never see, except on the original ram air option cars is the knob under the dash for the flapper to open the scoops. It is very rare on the 69's, not sure on the 8's or 7's.
The resto shops don't sell em. A while back there was a guy who had a couple for sale that were reproduced from the original I assume, and wanted 1K a piece just for the flapper. A bit steep for the average joe.

But, that to me, is what makes the ram air unique. The ability to open or close the scoops.

The '67s and '68s did not have a flapper valve system. I looked at modifying a GTO system but decided it was too much work and yet another opportunity for costly mission creep.

The '67-'68 scoops are not in a negative pressure area, but are too far back on the hood and too low putting them in a low pressure area. This location puts them in the worst part of the boundary layer of air moving across the hood. In other words the relative velocity of the air to the car is much less than the car's speed. For example, at 100 mph the velocity of the air hitting the scoop may be substantially less than 50 mph. Putting the scoops toward the front (ala 69 T/A) or high up above the hood (ala pro-stock racer) overcomes this problem. Facing the scoop rearward near the windshield (ala '70 up T/A) takes advantage of a high pressure zone of air. 1/2 psi can yield a measureable increase in HP so a well designed scoop can be worth it for those wanting to wring out every last HP.

As for the '67 to '68 system, it's just plain cool and that makes it worth adding for some of us.

"Negative pressure" is a little bit of a stretch. Pressure is one of those relative things. You first have to define what you're relating it to.

The hood scoops on both the Firebird and the GTO hoods are in the "boundary layer." The air does not move at the same speed as the air flowing over the car. This is actually a helpful thing as far as pressure is concerned. As far as the pressure distribution on the hood of the car is concerned, there are places on the hood where the pressure is "lower" than others, and in ALL cases (except 1*) it is LOWER than the ambient pressure. (Some dude named Bernoulli proved this about 300 years ago.)

In the example of putting the intake ducts behind the grilles, you'd be adding the stagnation pressure to the ambient pressure and increasing the density of the air (since it is a lot cooler than the air under the hood). This WILL require a re-jetting of the carb, since it will have the same impact as running at much lower altitudes. In the 70's, the early 2nd gen racing T/A had a 2x4 manifold and the shaker scoop faced forward. The dramatic changes in air density entering the carbs made them impossible to tune over the relatively broad speed range the car was racing at. In produciton, the 2x4 was dropped and the scoop was turned around. The reason this worked as Ram Air was because the scoop was above the boundary layer on the hood surface.

There is an area where the cowl meets the winshield where there is a stagnation of the airstream and the pressure approaches the ambient prerssure. The cowl induciton Chevelles capitalize on this fact. It's cold air and its at the highest possible local pressure.

*The one case is when the relative air speed over the surface of the hood is zero, i.e. the car ain't moving.

Shoot - I wish that guy I met recently would post on this thread! He's got a NICE ram air setup...

He removed the high beam headlight assembly from the grill, and ram two very large (3"?) tubes from the open headlight area stright to the dual snorkle air filter. B/c of the location of the intake - you're certainly getting air flow, if not too much of it! You still get the Firebird look of having 4 headlights, b/c the holes left behind are round - but you lose your high beams.

I'll see if I can get pics from the guy, or get him to post a reply here about his setup. I was impressed.

wonder where he got that idea....

I wonder if there's measurable drag reduction from pulling air out of the stagnation region in front of the grill?

With some simplifying assumptions, 455 cubic inch engine at 5000 RPM, assume 100% volumetric efficiency, displaces ~19,000 cubic inches of air per second.

Car grill sweeps 6 feet wide x 2 feet tall at 60 MPH is ~152,000 cubic inches of air per second.

So the engine could pump 1/8 of the air out of the way of the grill at 60 MPH. That ought to be measurable. Am I nuts?

all I know is they look and sound very cool....

Just might have to do it!

hey hammered
just received the template you sent me today for my ram air hood pan just finshed triming the hood and installing it fits perfect like a glove
almost looks like i knew what i was doing now the hood tach hole thanks agian i owe you big time

hey greg do it its pretty easy to do to install if you fel like your ready to tackle this project i'll pass on the template for the hood

These guys make aftermarket type under hood "ram air" setups

http://www.ramairbox.com/

that ram air on that fairlane or falcon is factory.ford made a car called the "thunderbolt".i have never seen an original but i have seen a few clones.it is a very rare car

Jim: Glad to be of help. I'm keeping the cut out in case I need to make a template for someone else - including me.

john

thanks again i'm really happy the way it came out
a little tweaking here and there but it looks and came out great!! your the man once again i'll be looking for you in dayton the cold one's are on me

According to someone i spoke with at the track, who's been racing 67-8FB's in Super Stock for 30yrs, it's worth about 2-3 tenths in the 1/4 mile, depending on outside temp's.

What about running a cold air kit? I've been looking for a universal one, but haven't had any luck. I think short of some major sheetmetal work, a cold air type kit sounds like it might be the way to go. Especially since no one wants to make a s/c or turbo set up for the pontiacs.

ramairbox.com sells generic kits.

If you don't mind cutting up the car (I do) you could drill several large holes in the firewall so it pulls from the cowl and fab a cleaner to seal up to it. (Cowl induction without the scoop).

I'm not a racer but, 2 to 3 tenths in the 1/4 mile sounds significant!

Hammered and bmxxxer, got any photos of your set up?

I've seen some expensive repo kits. I think it was on e-bay. $500+!

My hood is wrapped up waiting to be installed, but I have a picture of the cut out section about half way down on this page: John\'s Home Page

Ya, i thought 2-3 was alittle boastfull.
Would like to test it myself.

I could test one this year if anyone wants to lend thiers to me for a weekend