has anyone ever tried using an air grabber type of hood scoop such as the old roadrunners on a slant six car to push more air in without using a supercharger or turbo?

I'm just curious to see if this would do anything at all or not...

The 'air grabber' seen on 1970-ish Road Runners was not large enough to make a difference. On A-bodies, it's known that the late snorkel scoop did make a difference due to height and design... (I think Big D used one and posted result wayyy back a few years...)

-D.Idiot

It would succeed in getting cold air into the carb. Much like a cold air intake. As far as a "ram" effect goes? I doubt it would be very effective.

One of my favorite cars I ever saw was a crappy, rusty old Pontiac that used to drive around by my house. Primer black, rusted out, blown mufflers, etc... You could hear it coming blocks away. What I really loved about it was the hood scoop- the guy had taken a standard mail box and mounted it like a Hillborn style air scoop. On the side, the owner had painted "667 - Neighbor of the Beast". I always chuckled whenever I saw that car. I last saw it parked in an impound lot next to a junkyard.

I still like that budget hood scoop though.

Placement and size of the scoop is a tricky business. Intuitively you would think that a forward facing scoop would gather the air better, but due to the way air flows over the hood at speed it could be worse than no scoop. The rear facing cowl scoop can benefit from a high pressure area at the base of the windshield. To get it right you have to do some extensive testing. Computer simulation and/or wind tunnel tests are the most reliable way to do this but few of us have the money or facilities for that.

_________________
David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

On a relatively stock car a scoop will mostly add a small amount of MPH if anything. The trick is to have one small enough to not add a bunch of drag, yet large enough and in the airflow to actually be helpful.

The pop up air grabbers added aboot 1 MPH, but had little to no effect on ET.

The Demon scoop I use was worth aboot 1 tenth and 1 MPH.

Too big a scoop will simply fill up with air and become nothing but drag.

The twin opening on a Buick GS hood have been proven to actually suck air out because of the layout.

_________________
Official Cookie and Mater Tormentor.

I read somewere that ram air has little effect under about 130 mph. The ram isnt enought below that speed to overcome the engines own poer to suck air. The cold air would be good and there is also the coolness factor to concider, I say just do it.

_________________

Grandpa's 1974 Dart Custom 4 door 225 auto, Aluminum Radiator, 1920 Holley.

the rear facing cowl induction is the best, as there is postive pressure against the lower part of the windshield and negative pressure in the scoop, thus creating a vacuum like effect. A forward facing scoop really doesn't start doing any good until you hit about 190mph. Learned all this from HOTROD mag when I did my science far project in grade 10!

Cowl hoods are just aboot the most useless scoops you can use.

The idea that a scoop is useless until 130+ plus is ludicrous too. An engine does not "suck" air in, it creates negative pressure and air actually is pushed in by atmospheric pressure. That's why cars run best when the barometer is high.

Anything you can do to either seal off engine heat or ram air into the engine will have some benefit.

If scoops actually were useless under 130+ I seriously doubt you'd see them on so many race cars.

On the other hand, aerodynamics really don't come into play until you are over 100+.

_________________
Official Cookie and Mater Tormentor.

I am not trying to start a war with you, but you made my point, we see so many scoops on race cars, and they actually aren't really doing much. There is a lot of good info on them and areodynamics on multiple landspeed record sites.

My Jetta IV TDi has cold air (ram?) intake it is routed FAR away from any heating influences - I discovered it this week after replacing blown headlamp bulbs - the left hand side light has strange cover over it did nt seam to serve any use - and since it was a pain to reinstall i left it off temporarily - drove like that for the day - planning to reinstall the next evening - fuel consumption was higher than usual, and car didn't feel as torquey? - the higher consumption was more due to me using the accelerator more cause the car felt lazy and I was rushing - at speed (120KM/H) ish

performance was down - Had a look and noticed that the cover I removed was actually part of the ducting - engine was sucking in warm air.....

The intake is facing forward - 12 X 1 1/2 inches - on top of the the plastic grille - well hidden but located in the gap between the top of the grille and the bottom of the hood

Reinstalled the cover and the engine was back to its own self

_________________
Regards,
Fanie Gerber
It's never junk, it's just a part you're not currently using

http://www.valiant50.co.za
Just say I own a few Mopars

Agreed. If that were true, those under-dash vent boxes we like so much on old A-bodies would not function below 130 mph (which means they would not function at all). A properly-designed scoop works at speeds well, well below 130 mph.
Er...yes, and the one-word shorthand for a condition of sub-ambient pressure moving a fluid is "suction".
...provided the rest of the induction system is calibrated to account for it. Weird driveability faults can crop up just by pointing the air cleaner snorkel forward instead of sideways (there've been threads about this), for example.
No, that's just plain wrong. Where'd it come from? Aerodynamics has a large and exponential effect at just about any real road speed, starting at about 30 mph. At 65 mph, there is about 40% more aerodynamic drag than at 55 mph. At 70 mph, there is about 400% more aerodynamic drag than at 35 mph. Quick but good real-world data points here.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

"The idea that a scoop is useless until 130+ plus is ludicrous too"

big yes - I am going to test this - want the best location for a fresh air inlet - and found one on the cuda with a mopar supplied opening in a similar position as on my jetta

IF i can have say .5 bar pressure above ambient air pressure - at a given speed it will be the same as a turbo forcing air into the engine with .5 bar boost- at the same given speed - more inlet air pressure more HP?

and with a properly sized and located inlet it will help at speed...any speed

or am I completely of the track here - more mixture in more power out- colder the mixture in also more power out

_________________
Regards,
Fanie Gerber
It's never junk, it's just a part you're not currently using

http://www.valiant50.co.za
Just say I own a few Mopars

I was at a race a few years ago, and the guys pitted next to me were having all kinds of problems, with misfires, banging, popping, etc. Turns out they had added a sealed hood scoop since their last time out. It turned out they had to remove the hood, and put on an air cleaner (temporallily), to clear up the problem. The scoop made a difference in air flow. This was a 13 sec car.

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

If you don't think aerodynamics have any affect under 100 MPH, consider this. Have you ever seen an RC airplane ??? Was it traveling over 100 MPH ??? My friend who is an RC flyer used to complain about all of those "ricers" with huge wings on their cars. "What good do those do, they can't make any down force...." I asked him how his plane flies with such a small wing and at such a slow speed and he stopped complaining. The wings on the back just look stupid, but they do or at least they can work if set up properly.

_________________
There are 3 things that will live forever, cockroaches, Keith Richards, and Slant Six Dusters !!!

http://s4.photobucket.com/albums/y128/slantasaurus/

take a look around

And that, folks, is the problem. You can't eyeball it and get it right. This calls for real testing. If you're talking about cutting holes in the hood, most of us don't want to do many iterations.

_________________
"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO