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Motorcitydak
05-10-2012, 03:05 AM
I am building a '68 Charger, its a little more aerodynamic than a brick but thats about it. I want it to be much better than that obviously. I have been thinking about the design of the rear end lately and think I have a way to eliminate the horrible negative pressure area above the back glass that these car's are plagued with. This was addressed with the '69 Charger 500 by using a flush fit fastback type of rear window plug along with some other things. I think that that looks alright but I really like the rear window and stock sail panels. Here is a pic of the back end, this is not my pic, just one i found on google

https://static1.pt-content.com/images/pt/2012/05/68charger-1.jpg

My idea is to use brake air ducting to make vents in the sail panels (the triangle pieces on the sides of the windows just in case you dunno). I could make vents about the size of the sail panels and put maybe 2 hoses on each side that would be vented from either side via a scoop, probably on the vertical sides in front of the tires. I think that this would eliminate the negative pressure at the back window, reduce lift at speed and actually allow a rear wing to make me some downforce. Or should i put the vents in the dutchman panel? (the horizontal panel behind the window) Or both? What do you guys think??

exwestracer
05-10-2012, 04:33 AM
Steve,
Seems like the sail panel vents should do the trick. Just make sure you're getting air from a consistent HIGH pressure area. You'd think the Charger's "hips" would be, but that flat nose screwed up the airflow ALL the way around the car. Are you thinking about some sort of "Daytona" nose shape as well?

Ripper
05-10-2012, 04:37 AM
The Ferrari 599 has a nice solution to it. It would probably look real good on your charger.
https://static1.pt-content.com/images/pt/2012/05/2010Ferrari5993-1.jpg

Randy67
05-10-2012, 05:42 AM
I would do something like the Ferrari 599 above. Done right most people may not even notice it.

Motorcitydak
05-10-2012, 02:40 PM
I am going to do the '69 Charger 500 grill, already have the parts for it. Its basically the '68 Coronet grill and front part of the fenders to pull that off. I plan on completely blocking off any air flow thru the grill and making a front bumper/splitter to allow cool air to flow thru the radiator then out thru the hood. I want to route the engine air intake to the cowl to get at that high pressure air. I was thinking about having these vents go from there as well but i do not want all those tubes going thru the inside of the car. With the AWD, i do not know how much room there will be under the car for more large hoses. I also want rear brake ducting so I figured maybe 1 large scoop on each side may work. 2 separate ones may be better tho since the rear vents will probably use vacuum to get most of their air flow and I would not want that pulling air from the brakes. Since the sail panels are way out on the sides and really not all that big, it seems like i would be best off with maybe 1 vent in the middle of the dutchman panel as well

I got this idea after seeing that design on the 599, beautiful car! I just do not think I can open up the outside of the quarter panel like that and still have it look nice. My side windows are flush with that outside edge

Ill dig up some pics of the '69 Charger 500

Motorcitydak
05-10-2012, 03:10 PM
Here are some shots of how dodge tried to fix the aero problems in this car

https://static1.pt-content.com/images/pt/2012/05/69charger500galengovier-1.jpg

https://static1.pt-content.com/images/pt/2012/05/1969_dodge_charger_500-1.jpg

nine lives johnny
05-10-2012, 03:25 PM
i think your picking a scab into an amputation. i would throw try to counter the lift with down force, throw a wing on it and call it a day. it's a draggy car not much you can do for it other then the nose cone that's been mentioned.

Motorcitydak
05-11-2012, 08:42 PM
While I agree that it is not a good aero design, I think there can be ways to try to help it. If everyone just left the stock setup alone there would be no P-T hobby. In order to have a wing actually produce downforce, it would have to be in stilts to get it into decent air flow since there is a minimal amount at the height of the trunk lid. If I allow air to flow thru ducts by the rear window, that eliminates the massive negative pressure zone behind the window and would flow a decent amount of air backwards that can the then flowing thru a wing and producing downforce. With the wing that low on the car it can more effectively work hand in hand with the diffuser I plan on building

As for the front end, if I allow the car to eat the air that is coming at it, I can at least improve the aero a little. The engine will eat some of the high pressure air at the base of the windshield. The grill will be completely blocked off and the most effective spoiler (not wing) is a vertical plate. The radiator air will be routed from under the grill, thru the radiator then thru the hood which will push the oncoming air up every so slightly then feeding back to the cowl. The splitter Im sure will not be low enough to the ground to do much but it will be better than nothing and the brake ducting will also be routed from specific spots. The only area I plan on not completely controlling the air is after it passes the brake rotors and spills out from the inside of the wheels

Im pretty sure that each sail panel will be getting 1 or 2 vents in it depending on what I can fit. I also want to put a double vent in the middle of the dutchmen panel since I have easy access to the bottom side of that area rite now. All that stuff together should be able just about eliminate the top end of my car from aero drag, prevent a lot of lift at speed and let me have some decent downforce

LSfan70s
06-15-2012, 11:46 AM
I am going to do the '69 Charger 500 grill, already have the parts for it. Its basically the '68 Coronet grill and front part of the fenders to pull that off. I plan on completely blocking off any air flow thru the grill and making a front bumper/splitter to allow cool air to flow thru the radiator then out thru the hood. I want to route the engine air intake to the cowl to get at that high pressure air. I was thinking about having these vents go from there as well but i do not want all those tubes going thru the inside of the car. With the AWD, i do not know how much room there will be under the car for more large hoses. I also want rear brake ducting so I figured maybe 1 large scoop on each side may work. 2 separate ones may be better tho since the rear vents will probably use vacuum to get most of their air flow and I would not want that pulling air from the brakes. Since the sail panels are way out on the sides and really not all that big, it seems like i would be best off with maybe 1 vent in the middle of the dutchman panel as well

I got this idea after seeing that design on the 599, beautiful car! I just do not think I can open up the outside of the quarter panel like that and still have it look nice. My side windows are flush with that outside edge

Ill dig up some pics of the '69 Charger 500

Great idea for the hood. I'm planing on doing the same for a 68 Firebird.
Here are some cool pics of cars with that kind of system.
https://static1.pt-content.com/images/pt/2012/06/attachmentphpattachmentid127386d12023425-1.jpg

https://static1.pt-content.com/images/pt/2012/06/844127108_XaiCXL-1.jpghttps://static1.pt-content.com/images/pt/2012/06/844127177_XbHyiL-1.jpg

https://static1.pt-content.com/images/pt/2012/06/10822web-1.jpg

https://static1.pt-content.com/images/pt/2012/06/10821web-1.jpg

https://static1.pt-content.com/images/pt/2012/06/844127866_kWV9KL-1.jpg

Go for it! :twothumbs

Motorcitydak
06-21-2012, 08:09 PM
Thanks a lot for those cool pics, post up some if you start building yours

Tuske427
08-30-2014, 10:29 PM
A '68 Charger is a sweet car. It sounds like you also did some homework on the 500 and Daytonas. Weren't these cars developed with NASA engineers, wind tunnels, etc.? They obviously did thorough research and development on these cars with top folks and equipment of the day financially supported by a major corporation. Now I'm not saying that their execution can't be improved upon, but I wouldn't discount their work, either. Are there any books about the technical development of these cars you can read about, to learn what worked, what didn't, etc. Perhaps reach out to some retired engineers. The advantage you have is this car has been in a wind tunnel and raced by many teams. Perhaps that data can be located? I'd also study the old NASCARS to see what other teams did to their cars. See who won, lost, who had the speed records, etc. I'm thinking most, if not all, of the info you will need is already out there.

HellPhish89
09-03-2014, 12:26 PM
a hood that vents air from the engine bay and an engine bay belly pan would help the front quite a bit. at the back, i really like the idea of using the 599's cues. i think it would work well and if done right, look great. i think an important thing to do for the nose itself is actually create a passage way on either side so air isnt trapped as much against the front grill. a small pass through would help.