Attn: Maverick Man - product idea

Yes, my intent was not to save weight but to have a nice/high quality replacment that would match any car.

 

ive been studying diffuser design and function for a while now.

the outer most drops should be right on the out side of the leaf spring inline with the inner edge of the tire.

then the rest of the drops are mostly cosmetic in their location. i am going to be making rear diffusers for my and mo's cars. part of achieving proper function is to seal off the entire rear section behind the diff as possible and create the lowest point up front by the diff to the highest point in the rear.

if you were to make a sellable diffuser rear valance i would do the two drops on the out side of the spring and have the bottom of the diffuser go back further than the stock one to where it meets the fuel tank. i would put two more drops on each side of the licence plate or maybe 1 to 2 inches out from it.

then to make the rear valance/diffuser functionable would be a mater of the end user sealing every thing.

 

Are you talking about effectively sealing the complete underside of the car or mostly just at the rear? I would be interested in how you work out sealing the area across where the flutes would be interrupted by the rear axle or are you talking about making the flutes start at that point? These cars aren't very aerodynamic and any improvement in that department would be very desirable at speed.

 

just from the rear end back. and even not right up to the rear end.

with these cars its not possible achieve the proper aero design under it due to every thing under the car. it would require custom floor pans and then belly pans to cover the bottom from the front air dam to the rear valance.

with that being said their is plenty of room for improvement.

we plan on sealing as much of the area behind the diff to the rear valance with a diffuser design that i previously described.

mo is planning on driving 160mph in the next silver state classic. the first year he had a problem with the hood rising and then vibrating up and down. we did the air dam for the next. that caused the hood to be sucked down. you could even see the effect at freeway speeds. but he also noticed that the rear end felt a little bit loose in the turns. this could be just from the air dam but their was some other changes like he had his trunk full of his luggage and tools the first year and empty the second year.

so our plan is side skirts for the center section, a rear diffuser as described, and a rear spoiler or wing. also we are going to build a ride height sensing system that can be data logged. that should be able to tell us if and how effective our aero mods are on the car.

now back to on topic, a rear valance with some of the rear diffueser shapes built in would be helpful. even some flat carbon fiber pieces that fit the shape of the valance would be cool for the vertical parts.

 

Are you talking about something like this?

 

similar to that. that has a lot of problems with it to be truly functional. it needs to be sealed so no air gets between it and the car. also the vertical pieces need to extend past the rear of the car.

most of the diffusers on that site where that pic is from are more cosmetic than functional.

heres the diffuser from a ford GT. its very functional

 

I like your idea of building a piece(the rear valence) that could be built upon. Some guys just might want it for looks, some might want the advantage of any aerodynamic improvement and some might like both.

The design of the Ford GT diffuser panel was the reason for my question about the axle because the flutes begin just under the seat on that car and the entire bottom of the car is flat other than the diffuser. Those notches in the fluted area in your pic are where the rear of the control arms portrude through and are close to where our axle housing would be located.

 

their is not a lot of technical info on rear diffuser design in one place. their is a lot of discussion on lots of forum boards but not much that has actual results or engineering principals discussed that is applicable to cars like ours. that meaning rear live axle equipped cars. i did find a few sites that did explain the principals of diffusers and the engineering involved.
im sure i can create a working down force on the back of the car with a diffuser combined with a rear spoiler or wing that is not causing too much drag.
that is the fun thing with Mo doing the SSCC is that we get true high speed feed back of the modifications we make to his maverick.

 

I doubt there is much market for something like that vs a nice stock replacement.

 

im sure their is no significant market for a properly functioning diffuser but a valance with the diffuser look in it could sell pretty well. then if you want to make it functional you just have to work on the under side to do that.

 

IMO that would look terrible on Maverick. Lets just agree to disagree.

 

im doing it more for function than looks but done right i feel it can look good. agreed.

 

I always liked this look.

 

that looks awesome! the nice thing about drawings is that they can take some liberties with dimensions and dont have to worry about ground clearance.

 

Very true. It would be nice if it was easily removable for you to run the race and take it off afterwards. That's why I thought having the valance separate was a good idea. The diffuser on the GT is famous for getting creamed on slopes especially driveways and such, and they're fiberglass. They do make urethane replacements for just the flutes. The last time we had to get one of those panels from Ford it was around $1400.