A Gound Effects Question for Wayne

[Silvertop]

I’ve been looking over the 818 Photo Gallery on FFR’s website, and it appears that some photos taken of the 818S during early track testing show it with the front diffuser/splitter, and without it in others. My assumption is that the car was tested both with it, and without it.

My questions: Did the added ground effects make any significant difference in the way the car behaved on the track? Did the car exhibit any bad habits without it?

My 818, which is scheduled for production this fall, will be a moderately tweaked NA, and will be pretty much a pure street machine, though it may see the occasional track day at BIR, Road America, or Blackhawk Farms. I’m trying to decide if I need to order any of the optional ground effects. I know I don’t want a wing – at least not a big one. Maybe a mostly decorative rear spoiler, if I can find something I like. I probably don’t want the front splitter, unless it is needed for safety at high speeds, or unless it makes a really big performance difference.

You have probably driven the car both ways. Your thoughts?

[Xusia]

I am in the same boat and am very interested in the answer to this. I like the look of the front splitter, side curtains, and rear diffuser, but would like to know how practical these will on the street (i.e. are they so low that they'll get damaged easily?). There's a decent chance my car will see some track days, and I'd like to know if these items will be necessary for safety & stability at higher speeds.

[Wayne Presley]

The aero parts on the car work. The R had a diffuser, splitter out 3" skirts and the wing. The S had the splitter on it installed at 1", no diffuser, no skirts and no wing. The R without the wing was loose , with the wing at 10° AOA was tight, wing at .2° AOA it was just a touch loose and really fast. For most drivers, I'd have the wing at 3ish° for the car to ultimately push in high speed corners (60+mph) while still being able to hang the rear out in the lower speed corners with the throttle. It is really nice being able to tailor the handling with just a wing angle change. Neither car had the full flat bottom that the production cars will have or the new R splitter that is on the production S model at the open house. So my best guess is both cars will be slightly aero tight, and slightly mechanical grip tight.

[joshuo]

Thanks Wayne. Does the wing make sense on the S? I was worried about the windshield robbing the wing of clean airflow.

[Silvertop]

The aero parts on the car work. The R had a diffuser, splitter out 3" skirts and the wing. The S had the splitter on it installed at 1", no diffuser, no skirts and no wing. The R without the wing was loose , with the wing at 10° AOA was tight, wing at .2° AOA it was just a touch loose and really fast. For most drivers, I'd have the wing at 3ish° for the car to ultimately push in high speed corners (60+mph) while still being able to hang the rear out in the lower speed corners with the throttle. It is really nice being able to tailor the handling with just a wing angle change. Neither car had the full flat bottom that the production cars will have or the new R splitter that is on the production S model at the open house. So my best guess is both cars will be slightly aero tight, and slightly mechanical grip tight.

Thanks for the detailed response. I confess that I had to read it about 6 times before it started making sense to me. :p

I still have a couple of questions, though. How did the S behave on the track with just the splitter? And did you ever have an opportunity to test it at speed without it? In other words, what effect is the splitter likely to have if used by itself?

Looks like you guys are having a good time at the Open House. I wish I was there. I'm glad people are taking the time to post stuff during the event. Allows me at least a peek.

[Turboguy]

Neither car had the full flat bottom that the production cars will have or the new R splitter that is on the production S model at the open house.

Thanks tons for your input, Wayne.

Are you aware of what the differences are between the "old" R splitter and the "new" one?


I'm also curious if you think the new flat bottoms might create enough downforce to alleviate the need for a wing on the R to balance the F/R grip? To me, that big rear wing on the pre-production R (with the small windscreen up front) destroys the visual 'balance' of the car. I want mine to be fast, but I also want it to look good :)

I wonder if there are any spy shots (or photochops) out there of other rear wings on the R? Maybe something that's effective, but less imposing.

[bnr32jason]

Oh good, I just asked that question in another thread. I'm glad to hear the production versions will have the full flat bottom.

I also agree that the wing on the R is just too damn big. I understand that it's functional and great for the track, but it's entirely too big for the street (my opinion of course). I think a smaller/lower wing would complement the looks of the 818S quite well.

[Xusia]

^What he said!

[Silvertop]

^What he said!

Me too!

[RM1SepEx]

Dave indicated that they had a prototype, "lip" spoiler vs a wing.

[Silvertop]

Dave indicated that they had a prototype, "lip" spoiler vs a wing.

That's good to hear. Something I would definitely consider -- along with the front splitter.........

[cmcintyre]

Here's what Some of the Aero looked like at the Open House
18441Skirt Panel
18442Front Splitter
18443R Diffuser
18444S Diffuser (or Not)

There was also a distinct lip on the trunk lid, Jim saying they were still tweaking that.