Anyone with data acquisition ever do back to back sesions with and without their front splitter? I was wondering how much of an effect they have on our cars. Was corner speed higher with it? Was accelleration down the staights better or worse with it?

In general they are good because:
less air under the car = more down force
flat bottum surface = front down force from venturi effect
High pressure point on lip = front downfocre

In general they are bad because:
added weight
drag could go up making the car slower down long staights
less air to cool the front tires could mean tire get too hot = less grip
less air to cool the transmission.
Allways fixing them when you go off track

 

I don't know if any one has any hard data but...

HT user "juantushag" Aka Renan- had a pretty bad push in his car (92 civic SI). Put a spliter on it and was much much happier. Going off of my memory...

I remember years ago the WC guys were saying that at some courses the spliter and air damn could be worth as much as 1 to 1.5 seconds in qualifying.

I am doing testing this weekend and while i wont be running with out the spliter this weekend i ran with out it last and the car was pushed horrible bad... So we will see.

 

No more front end float on 120-130mph straight.....

 

I really need to get me a daq system to start testing some of these things myself.

 

I've been trying the data acq, but the stopwatch still tells all?

 

i don't have any hard data either, but when i could keep one on my car the fast stuff felt much better. your high speed turn in is a lot more confident feeling.

 

I've actually got data for this at two tracks: Willow Springs and Buttonwillow CW13

At Willow, I lost a splitter in turn 8 at 117 mph with five laps to go in a H4 race back in 2007. Tom Paule has a photo of me and the detached splitter and I'm sure he'll chime in sooner or later with the said photo. I was turning high 1:37's right before the splitter let go and then when the splitter was gone, my lap times went to high 1:38's (1.2 seconds higher average for the four laps). The car felt noticeably worse in all corners (even the 70 mph Turn 3), but especially in the 100+ mph turn 9. The feeling was like I got a flat tire and the car just didn't want to turn. When you get used to the car handling a certain way and then you immediately lose a good amount of grip, even if it's only 7 to 10%, it is very noticeable.

The one thing to keep in mind about all of this is that the car wasn't set up to run without a splitter. If I would have changed the setup on the car, such as removing the wing and changing some alignment parameters, the lap time differential wouldn't have been as great. Having a rear wing will add to the loss of front grip and at the same time add to the overall drag. So you loose some grip and you gain some speed on the straights and some large radius corners. The overall loss or gain in performance would certainly be track specific, the type of car (and the power of course), and some other factors.

On the other hand, At Buttonwillow, on course 13CW, the splitter and wing were good for about 1.5 seconds a lap in back-to-back-to-back testing. However, this was comparing a car with splitter/wing and the same car without splitter/wing. Because of time limitations, the car was not optimized for the wing/splitter setup, but I think it was close.

 

Data acq won't do anything or tell you any more then the stopwatch if you don't know how to use the software.

But if know how to use the software, it is much much better then just a stopwatch.

Also it will tell you exactly were you made up the time, which is important as you might nail corner 3 that your working on but then be held up, or mess up in another corner and you're overall laptime suffers.

I didn't really appreciate the power of data acq until I had spent several hours with a few different people who are very good with data. Then you can truly appreciate how powerful data is.

I'd serously suggest getting a book, or sitting down with some one really good and having them show you some basic things.

 

Just an anecdote, no data - years ago when the USTCC guys first came up to Portland, Kiwi or somebody had some contact and lost their splitter and front bumper cover, and I thought "Ah, they should start falling back", but they didn't. They stayed in the hunt in the lead pack. And I thought "WTF?" Maybe it was like when you lose a sense, your other senses become more acute to compensate? There's too much science in modern racing. It's still about magic. But science + magic = ALL your base.

Scott, who is not getting enough compensation from his other senses...

 

Does cleaner underwear count as data acquisition?

 

Absolutley