[Formulabob]

I recall reading that airflow separates from a flat place (diffuser) at an angle greater than about 11 degrees. I have religiously kept the angle at 10 on all my flat surfaces.

Hence the length of the duffuser is governed by racing rules and that 'magic' angle.

Also You want the (outer) strakes as close to the ground as possible.

Anton

1. You are VERY safe at 10 degrees.
2. My statement is derived from actual F1 testing although it is more than five years old.
3. A flat plate angled at some angle is not representative of our diffusers. It lacks a very low-angle and relatively long entrance section, i.e., the underbody ahead of the diffuser. This entrance section is one of the other factors alluded to in my post.
4. "Outer strakes as close to the ground as possible" is an O.K. Rule of thumb but may not provide the optimum air management on a sedan/sportscar (non open wheel car). Hint -- managing the "dirty" air is important too.

However, I doubt that anyone on this forum can feel or use the last kilogram or two of downforce on our cars. Also, few on this forum have the knowledge, time, patience, facilities, and money to pursue that optimization. So, I'm going to quit posting suggestions for optimizing our cars -- at least in this thread. That way I won't get upset over being contradicted.

All the best to EVO11 in his racing!!

 

[evo 11]

 

[evo 11]

.

 

[evo 11]

Hi Guys, hope you are still here

I was on the way to take victory in the first race... but on the last lap I have lost power caused by check engine, I had 25 seconds advantage over the second one....

on sunday I have won the race.

I have new very dangerous opponent with s2000 engine
His car is build similar to WTTC car, engine is moved to the back by 60 cm.

BTW I have improve my lap time so now its exactly 2sec gap vs my car with 500HP engine.


some pictures and on boards:

 

[evo 11]

btw this bmw is extremely fast so I have to search for additional seconds...

I have ordered proper race wing.
I'm thinking about stiffer springs...

Simon, I don't know have you ever tried Yokohama from WTTC but donlop is nowhere vs this tyre.

I was 1,5 sec faster on used WTTC yoko vs brand new set of dunlops u.k.

 

[evo 11]

I did some clicks on dampers and here is the result.

BTW thanks to Vulcan Grey great advice on the dampers settings.

 

[evo 11]

 

[Vulcan Grey]

I did some clicks on dampers and here is the result.

BTW thanks to Vulcan Grey great advice on the dampers settings.

https://www.youtube.com/watch?v=s9vIOoG_aIM

Hi Karol,

Glad I could help. Looks like you are having fun!

 

[evo 11]

Hi Karol,

Glad I could help. Looks like you are having fun!

true

I'm running stiffer springs and more rebound

 

[evo 11]

 

[evo 11]

He was right....with the wing too

your probably not going to want to hear this but:

1) the dunlop rears you have are never going to work on an Elise (they are for much heavier cars), go back to their 235/610R17 and the matching 200/580R16 front, on J8.5 and J7 rimms.

2) your not running anything like enough spring rate, then using the dampers to try and prop the car up, the result is snappy handling and no basic mechanical grip

3) that rear wing is useless - actually worse than useless, get a proper profiled one NOT from a tin-top

on the right tyres and setup, no reason it should not corner much better than that, eg:

https://www.youtube.com/watch?v=Ic7uMC3NQO4