Why trailing fenders work

Secrets, tips, tools, design considerations, materials, the "science" behind it all, and other topics related to building the cars and semi-trucks.
Post Reply
User avatar
LightninBoy
Master Pine Head
Master Pine Head
Posts: 203
Joined: Mon Feb 20, 2012 9:09 pm
Location: St. Paul, MN

Why trailing fenders work

Post by LightninBoy »

Here's a short video I took at the Minneapolis Science Museum. This exhibit was one of the inspirations for the X3 fender design, a design which is now dominating all the wide wheel league races (where fenders are allowed).

Although I haven't tried it to be sure, this does suggest that just a trailing fender is better than no fender at all. I think that is something to consider if you like to run a long wheelbases in scouts for extra stability that leaves no room for a front fender.


https://youtu.be/
User avatar
whodathunkit
Pine Head Legend
Pine Head Legend
Posts: 2475
Joined: Sat Apr 25, 2009 5:56 pm
Location: Forgan, OK

Re: Why trailing fenders work

Post by whodathunkit »

Cool video.
Thanks for sharing it LightninBoy.


Sent from my iPhone using Tapatalk
What type of automobile can be spelled the same forwards & backwards?
bracketracer
Pine Head
Pine Head
Posts: 85
Joined: Sun Mar 24, 2013 11:08 pm
Location: St. Louis, Missouri

Re: Why trailing fenders work

Post by bracketracer »

LightninBoy wrote: Although I haven't tried it to be sure, this does suggest that just a trailing fender is better than no fender at all. I think that is something to consider if you like to run a long wheelbases in scouts for extra stability that leaves no room for a front fender.

Definitely an idea worth testing! One concern I have is that the display in the video is basically a thick 2D representation, it doesn't allow for lateral flow? Air striking an unprotected wheel tread moves to the side quite a bit. Which I know you know, since the LB-style fenders greatly reduce lateral flow.
User avatar
ciodude
Master Pine Head
Master Pine Head
Posts: 283
Joined: Wed Apr 04, 2007 1:34 pm
Location: Charleston, WV

Re: Why trailing fenders work

Post by ciodude »

Does a racer even get up to a speed where this is a real issue?
User avatar
Vitamin K
Pine Head Legend
Pine Head Legend
Posts: 1227
Joined: Sat Apr 20, 2013 7:26 pm
Location: Spotsylvania, VA

Re: Why trailing fenders work

Post by Vitamin K »

ciodude wrote:Does a racer even get up to a speed where this is a real issue?
Yeah, league performance and track tests definitely show improvements from fenders.
chromegsx
Master Pine Head
Master Pine Head
Posts: 166
Joined: Wed Jan 18, 2012 9:25 pm
Location: PA

Re: Why trailing fenders work

Post by chromegsx »

ciodude wrote:Does a racer even get up to a speed where this is a real issue?
Typically the answer to this will depend on how good the rest of your build is. More important things come first. alignment, weight placement, wheel prep, etc. Once one gets those things near perfect, the aero factor should be considered. But the short answer to your questions is yes. Aero can and does play a factor. Even more so as you move the COM back and making the front end lighter.
User avatar
davet
Master Pine Head
Master Pine Head
Posts: 539
Joined: Wed Jan 16, 2013 1:33 am
Location: MN

Re: Why trailing fenders work

Post by davet »

That video is why we built our car as we did. Thanks.
Post Reply