I'm working on designing and building a new front splitter for my IX for this year's NASA TT series.

The #1 problem I've had with my Evo has been the front brakes. I've never had cooling ducts, and tend to murder my rotors with heat until they warp so badly my session is done for the day if I'm trying to set personal lap records.

I've picked up an APR front splitter, a spare IX front skin and a Rexspeed FQ series copy air dam.

I'm going to build a duct section into the top edge (high pressure side) of the splitter to force air over the front rotors which will obviously steal from downforce, but I'm not caring about that at the moment, mainly cooling for the front rotors/calipers.

Searching Google, I can find a lot of theories and arguements over splitter size, angle, and length, but I tend to take Google search results with a grain of salt anymore.

Anyone have any good references for aerodynamics, or more specifically data on front splitters? Any help would be really apprechiated!

Opening size will be approximately 2" x 24" which is almost the equivilant of an 8" diameter round pipe, which should be plenty of air.

 

You heading to TT2? or TT3 and eating the aero adjuster?

OEM Front Calipers? What Rotors?

 

I believe it had everything to do with the drag coefficient of the shape of the front spliter causing negative lift or downforce to the front. I remember one of my close friends talking to me about it but can't really recall much else.

You would imagine APR or some type of race composite company has some data on the angle and shape of Front splitters and at what speed does it provide x amount of downforce.

 

The APR is mostly for looks in stock form. They actually are slightly upturned when installed on the factory air dam and don't seal the gap in the center section at all. Not a big concern since I'm using it mainly to direct airflow. A previous thread from Jid2 said 0 - 4 degrees downturn is correct, but no info on length. I'm worried about rules stating splitters must not protrude past the factory bodywork, as the bottom lip sticks out past the bumper as is.

 

What class will you be in ? TT 1/2/3 ?

 

If you are interested you can read my small build thread:
http://blog.365racing.net/2012/04/02...plitter-part2/

I've had to change a few things over time. Through testing, I've estimated there is 250+lbs of downforce at 160mph. lol

 

I assume TT3, I'm still trying to figure that out!

Nice build thread Evoizmm!!! those side bracket pictures will really come in handy when I get to the support stage! Thanks for the resource!

SSCA has a rule the splitter can't extend past the body work which is confusing, my IX front lip sticks out as far as the bumper. Does NASA not have an equivilant rule? I also run Hillclimbs with the NHA that follows SCCA tech. I doubt I'd get protested with the group I run with, but hey, no excuses!

 

NASA has no rules for the splitter in the TT Hp/weight classes.

SCCA does have rules for splitter's but they vary from class to class. It shouldn't be a problem in regards to tech.

I still havn't ever seen any good info on how far a splitter should stick out. You don't usually see huge splitters on any of the professional series cars out there. I'm not sure if that because of rules or because they actually have tested this stuff.

 

What class do you run it? If its SCCA classing then you can always claim your running ITE. Most regions will have something along that line that will allow for unclassified cars to run. Or, i would suspect you guys have some some sort of specials class for the formula and purpose built hillclimb cars that you could run.

 

in my opinion and from the hours or reading ive done on the topic, you should be able to start feeling a noticeable change in the 2 inch range. last year i believe most time attack rules (at least GTA, which i think matched NASA) was that it could extend a max of 5 inches. but what i havent been able to understand/what seems to be kept secret, is what is the "best/ideal" length. honestly i think its all gonna come down to what you can balance out with the rear wing to make sure you arent putting understeer back into the setup.

 

http://www.timeattackforums.com/foru...lations-2.html

Not conclusive but.. Good read

 

Most race series have rules on splitters. I like having aero unrestricted (NASA TT1/2), it encourages ingenuity. 99% of us don’t have access to big dollar testing facilities (but that doesn’t mean there are other means of testing).

 

Turns out I'm in TT2 I think. 7.72 corrected, but I can get it to 8.0 without much work.

I read that thread already, but ran into the same delima, how long is too long? At PPIHC in 2010 Monster Tajima's car had a 14" long splitter or something rediculous.

 

In response to this. The highlighted nails it:

Going to have to test it out a bit until you get a right. Glad I'm so slow it doesn't matter

 

5" is a good place to start. Balance with the rear is key and being able to drive around town if needed. Things get pretty dicey with even 5" mounted level.

This is my standard photo.