CLASS RACER FORUM
Page 3 of 4 12 3 4
Show 40 post(s) from this thread on one page

CLASS RACER FORUM (https://classracer.com/classforum/index.php)
-   Stock and Super Stock Tech (https://classracer.com/classforum/forumdisplay.php?f=4)
-   -   aerodynamic drag and body style (https://classracer.com/classforum/showthread.php?t=76953)

gsa612 08-08-2020 08:06 PM
Re: aerodynamic drag and body style
 
Back in the day a few stock and S/S cars ran a vinyl roof claiming the pebble on the texture was worth some MPH,however small the gain was.FWIW,Jason Line's Buick GS has a vinyl roof...gsa612

Mike Rietow 08-08-2020 11:56 PM
Re: aerodynamic drag and body style
 
Quote:
Originally Posted by Jackie McCracken (Post 620425)
On a 79 Malibu wagon the factory rear spoiler is worth almost 3mph on car that runs just at 100 without it in the quarter.. and the reason for it is that it pulls air from the roof and routes it down the back window (to keep it clean in civilian life) which fills in the vacuum hole behind the car. and if you're wondering how big and powerful that "vacuum hole" is, it is what the cars that make turns use to create their ground effects downforce in sufficient quantities to be able to drive one across the ceiling upside down. The "vacuum hole" is also the reason behind drafting in nascar, if you can get in close enough it will damn near pull you along... need proof of what good aero can do? How about 174 on a bicycle...peddling.

what you really want to do with the front of the car is to smooth the air and keep it out from under the car, along the sides and roof you need to keep it flowing smoothly, and a the back you need to eliminate the "vacuum hole"...


Jackie
Wow, excellent post.

This Chevy II has a All Pro RR 427 sbc we're getting ready to race with a 300hp NOS cheater plate per the rules of DXP Street, the car will be around 140mph 1/8 mile. We have the bumpers off for chroming but we still gotta ad a splitter under the front bumper. I'm more curious about the wake behind the car. Do you know anyone who has added a rear deck spoiler? This is a leafspring 275 radial car with a set of shocks on the back with a two way adjuster on rebound the azz of the car is up at the stripe to keep the nose down, you may have seen this on radial tire cars, not real conventional for drag racing but the shocks help get the power in the car early no wheely bar allowed by rules.

I'm just fishing around for Ideas, I think we can keep the air from under the car fairly easily.with a chin spoiler under the front bumper.

Are these chevy II's known for wake issues? the rear deck is long relatively speaking. I was thinking rear deck spoiler, not sure, looking around for experience with these cars. Would rather no spoiler.

Thanks ahead of time

.https://i.imgur.com/Mv5iQCE.jpg

Adger Smith 08-09-2020 01:21 AM
Re: aerodynamic drag and body style
 
Larry, you have e-mail.
Sorry couldn't get the excel to post here
are you still using the "Woodfinlarry" mail?

Adger Smith 08-09-2020 01:27 AM
Re: aerodynamic drag and body style
 
1 Attachment(s)
This car was pretty aero..

Adger Smith 08-09-2020 01:29 AM
Re: aerodynamic drag and body style
 
Sorry no chart

GTX JOHN 08-09-2020 02:53 AM
Re: aerodynamic drag and body style
 
Quote:
Originally Posted by Jackie McCracken (Post 620425)
On a 79 Malibu wagon the factory rear spoiler is worth almost 3mph on car that runs just at 100 without it in the quarter.. and the reason for it is that it pulls air from the roof and routes it down the back window (to keep it clean in civilian life) which fills in the vacuum hole behind the car. and if you're wondering how big and powerful that "vacuum hole" is, it is what the cars that make turns use to create their ground effects downforce in sufficient quantities to be able to drive one across the ceiling upside down. The "vacuum hole" is also the reason behind drafting in nascar, if you can get in close enough it will damn near pull you along... need proof of what good aero can do? How about 174 on a bicycle...peddling.


what you really want to do with the front of the car is to smooth the air and keep it out from under the car, along the sides and roof you need to keep it flowing smoothly, and a the back you need to eliminate the "vacuum hole"...


Jackie
ON my Aspen Wagon = a similar class to the Malibu
Wagon.....It slow the car down a MPH with the rear
factory spoiler!

Billy Nees 08-09-2020 07:49 AM
Re: aerodynamic drag and body style
 
Just for discussion purposes.
https://www.youtube.com/watch?v=VUiGhyHC-1A

Dwight Southerland 08-09-2020 08:07 AM
Re: aerodynamic drag and body style
 
Billy, that's just a justification for not doing body work.

Chris Hill 08-09-2020 10:20 AM
Re: aerodynamic drag and body style
 
Quote:
Originally Posted by Steve Polhill (Post 620354)
Hey Larry watch this video. in this case the front end was a disaster for drag but the most gains were picked up with work done on the rear of the car.
https://www.youtube.com/watch?v=1X35-bGWpEY
Great video and thanks for sharing.

FED 387 08-09-2020 10:41 AM
Re: aerodynamic drag and body style
 
Looking at that RMS pic notice the ground hugging stance that the vehicle has---Air going underneath a car is "dirty air" and its trapped in all the nooks and crannies---better off getting the air to go over or around rather than UNDER for this reason---Why do you think NHRA has a blurb in the rule book about no underbody streamlining??? Just for that reason. FED 387


All times are GMT -4. The time now is 04:23 PM.
Page 3 of 4 12 3 4
Show 40 post(s) from this thread on one page

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright Class Racer.com. All Rights Reserved. Designated trademarks and brands are the property of their respective owners.