63-67 b body- reducing drag coefficient

hey guys: Anyone done any work on cleaning up airflow/turbulence on mid/late 60"s B bodies?

I cannot help but notice the front of the K member area catches air badly as well as other areas.
Not finding much info.
May start another thread for the late 60"s b bodies and one for the A bodies through mid 70's.

from about 70 mph up these areas certainly, effect et/mph so i thought I would ask if anyone has worked on reducing air turbulence /drag.

Thanks

Get the car as low as possible, and put an air dam on the front, under the bumper.

I think Chrysler recognized back when the cars were new. I've seen a lot of photos of the '64-67 cars with an air dam located as stated above, below the front bumper. Some racers rolled their's around underneath, creating a small belly pan effect. There was also the factory "bubble" windshield for the '65 FX cars.

anyone have links for pics?

One cheap way is to paint most all jagged edge parts gloss black, especially the big K-member. Gloss paints are more slippery in the air compared to the stock look of matte/satin finishes of the day.
Dams can be constructed as said and serve two purposes for speed and safety. I've been planning on creating one out of aluminum sheet to be detachable or reinstall able at any time at the track for a street/strip setup.

The name of my car is the "Blunt object " It cuts right thru the air !

indeed bigdad.
Wonder what the results would be of closing up the front holes in the Kmember with light alum on one with stock kmember.

We put a Gerst suspension on the duster and one can visually see a huge difference in air catchment between it and a stock k member.
I'm willing to bet even money that cars with stock k member are harder on engine cooling than cars with a Tubular k.

That there is the boxiest that they come, but beautifully designed and most sturdiest for dragging.

IIRC a panel covering the open space between the bottom of the front pan and the K member helps, but it increases oil temp.
You're probably catching air under the trunk, but what to do?
For best effect the dam should be as low as possible, a rubber skirt bottom (I've seen garage door skirts used) gets it closer without being wrecked when the nose dives, curbs, driveways, trailer ramps.
If legal (or you don't care!), it should project forward ahead of anything else, and angle back ending at the radiator core bottom.

I made dams for my rear bumper years back out of aluminum thin sheet. Large area of catch basin back there that also slows those cars down. Lots of air management is more effective underneath more than up top sometimes.

Good thoughts Poly.
On the 65 k member area, there are two areas that together make up about a 2.5 sq ft parachute!
If i fill those in with thin alum., the deep pan remains fully exposed to air flow but the bottom of radiator core support to k member now directs air down and back towards oil pan.
I think it will work, look nice and clean up that air path from a catchment, turbulence area to useful airflow.

I hadn't thought about looking at the rear bumper, will do so this weekend.
Do you have any pics on how you did yours?

Yes I do, but I would have to look through quite a few photos. Be patient being that I'm busy traveling.

Thank you !

I have a Gerst front on mine too

Aero works like this: oncoming air that gets into the engine compartment, hits undercarriage projections, and which eddys behind the car all create drag, lift, and slows the car; also requires a lot more power to overcome at steady high speeds.
'66-'67? Look at Petty's Cup car towards the end of the '67 season: gaps closed up, sits low at about 5-degree rake, tight/faired bumpers. See also Smokey Yunick's infamous Chevelle and TransAm Camaro.
Keeping the air from getting under the car (air dam) solves a lot of it, because that air hits & bounces around everything.
For a drag car, not enough time is spent at high speed to make all the tricks ET-effective, plus there's weight to consider.
But addressing the nose, reducing grille intake, removing or smoothing things that catch air, all help aero.
A short rear spoiler also helps passing air attach to the trunk lid and cause a tapering effect behind the car, which reduces drag and reduces lift.

Thanks Topside

You're quite welcome. "But Wait, There's More", haha...
Aero research on vehicles pretty much started with the Germans in the 1930s, and other sources for info would include an article by Car and Driver using a Dodge B-van, teh 2nd versionof the original '65 HemiCuda drag car, the Chrysler engineers' work with the Charger 500 & wing cars, early on in the TransAm series when they started drooping the noses, and later when the windshields were laid back a little and the upper cab subtly reshaped (Yunick's '68 Camaro) into a more fastback shape, drip channels set flush. That car & the Chevelle Cup car had a lot of underside fairing done, even with their creative ft air dam work.
A 3.5" rear spoiler at a 45 on the back of Melrose Missile VII picked up about 6-7 MPH and about .4 ET IIRC, though that was a 160MPH+ car on fuel at the time. Basically the car was spinning the rear tires from lift.
Bang for buck on a drag car like a '66-'67 B would likely be blanking off openings within reason, dropping the nose, and an air dam; reducing the frontal area would be nice, but a lot of work.

LOL, I have the WORSTE a 66 coronet! The grill is FLAT, ugly and a total air trap! I don't think they even tried the 66' Coronet on super speedways, it was OBVIOUS that they were an air plow!

https://en.wikipedia.org/wiki/Boundary_layer_thickness

Has anybody run a B Body at speed (around 150) with the bumper/K Frame closed off? How about the rear below the trunk floor to bumper. I'm wondering if it creates any lift? I can't run an air dam or spoiler do to rules. The underneath pans at the front and rear are interesting.
Doug

I've run a thin aluminum air dam underneath the trunk floor to the rear bumper for years, but one; I've never reached or breached the 150 MPH point, and two; I've never looked at my mph figures after doing such advancements.
Too much to explain, but I strongly believe the trunk to rear bumper is a huge subterranean parachute and when closed off rather easily, can make some eyebrows lift, not the car.
I've even thought about foils and small dams at perpendicular points of the chassis ie: Trans and torsion bar cross member, rear spring hanger members, all painted slippery gloss, etc.) where they could lend a hand in underbelly air management. This could/would be equivalent to lowering the car all together.
I was even thinking that swooped muffler designs would help a whole lot in street/strip applications.
Mufflers, talk about an underbelly 55' Chevy shoebox right in the air stream.

The grill is FLAT, ugly and a total air trap

Move it forward as much as you can (like the Charger), and blank the areas that don't directly feed the radiator core.

Before building fancy stuff hoping for improvements you can always experiment with duct tape first and replicate the stuff that helps with sheetmetal after improvements are verified/justified

i can create a crude set of wind tests here either in my paint booth or in a big tent i have.
Wind i can create and i have high end fog machines so i can direct visible air flow over the car, was hoping for ideas, pics from others that had done things they knew worked in order to save time.

If i flow the car, will try to let yall know what i find out.

IMO (idea), coast down tests are more useful to the backyard DIY, if you can replicate accurately on a closed road section(?), both directions. But "GIGO" still applies. It would be hard to understand reliably others interpretation of backyard tent wind tests.

If you are indeed serious, I would go down the path of nearly completely covering the underside of the chassis, as much as possible, from a wind drag standpoint, in that that would give the best you can achieve from that side of the car, It would not need to pretty or elegant, just be cheap. easy, not flap, nor detach or catch fire. You would then know the ultimate target and reward for any chassis streamlining, and whether its worth it or not. Then you can go after the other 5 sides.

As soon as I get back home, I'll flick the special parts on my car to give you an idea of what I've done to cut air or at least manage it.