Track Speeds/Layout

Does anyone have any information on track speeds seen on the autocross course at competition? Additionally, does anyone have information on the layout of the autocross course? I'm trying to determine the benefit of designing aerodynamic aids for my vehicle so any information concerning the maximum or minimum speeds in the straits and corners would be helpful.

Paging Robbie.

We've discussed this before, but not always to consensus haha. 

At the challenge, autox speeds between 30-60 are normal, some cars may touch higher than that for a few moments. They usually have corners designed to haul you down to 30 or so not matter your car, so don't expect to be able to "average" 45-50 necessarily. 

In general, I do think aero helps at the challenge. But probably more in concour points than in actual time on the autox course (an extra concourse point can be worth a lot of time). For autox my belief is that you want as much aero downforce as possible, all the time. For drags, drag does matter - a little bit - so reduce it if you can.

What's your car and plans? Would love to hear it.

What is the event order?  

Usually autox day, drags that night, concour the next day.

On the year we had removable front and rear wings, that meant we had to install, remove, install, which turned out to be a lot of work on top of the other issues we were dealing with.

In reply to Robbie (Forum Supporter) :

So if I berk the engine at the drags can the roller sit in for the concourse?

In reply to AnthonyGS (Forum Supporter) :

It happens all the time! 

Robbie (Forum Supporter) said:

On the year we had removable front and rear wings, that meant we had to install, remove, install.

There are a lot of good concepts that could work well like two aero setups, two suspension setups, two complete wheel/tire combos. Although great for optimization there is only so much time in a day to make the swap, unless you have a larger team and an already sorted car with you. 

Like any autocross 30-70mph I think aerodynamics are only good for a few tenths on a 45-60 second course. A lot of additional work for little gain, but they look awesome on a race car so please add a splitter and giant wing.  

In reply to Robbie (Forum Supporter) :

Thanks for the info! I'm currently a member of the Cedarville team. We brought the Nash Metropolitan to competition back in October and we're working on making it better for next year. I was assigned the job of improving the aero on the car and I'm trying to decide what mods are worth my time pursuing. Right now I'm in the early stages of designing a diffuser and needed to know what speeds I should use for simulation and testing.

In reply to stbsvsdnkn :

I remember your team! That car has serious potential. Good luck with the build.

I loved the Nash! With a little sorting that thing should run with the best.

Aero at these speeds on our FSAE car made about a 1 second difference on a 40 second course in testing.  It was noticable enough that a change in the distance vs speed approach to navigating linked corners was needed.  It's not HUGE and on a fullsize full weight car will have less effect but I think if you have the bandwidth it's worth it.  And Because Racecar. 

Also, I had the LMP360 and spent about 20 minutes talking to your team about chassis and other items.  Feel free to have the chassis team (or any members) reach out through the forum for design review or to bounce ideas as you work on the car.   Or just post up a thread.

Even if the aero bits have zero effect, they'll gain you points in the concourse on visuals alone.