Presented by Nine Lives Racing
1 2
Johnny_at_NineLives
Johnny_at_NineLives New Reader
8/9/21 4:48 p.m.

is there any way you can not use that overhang bumper?

On the miata's with an air dam, we ditched the overhang. we were able to increase down force 300% with almost no drag increase. 

DeadSkunk  (Warren)
DeadSkunk (Warren) UltimaDork
11/1/21 7:19 a.m.

In reply to Johnny_at_NineLives :

How do you get rid of the over hang on a Miata? Pictures?

sleepyhead the buffalo
sleepyhead the buffalo Mod Squad
11/1/21 9:27 a.m.
DeadSkunk (Warren) said:

In reply to Johnny_at_NineLives :

How do you get rid of the over hang on a Miata? Pictures?

Finally CFD done on My miata.| Aerodynamics forum | (grassrootsmotorsports.com)

Gimp (Forum Supporter)
Gimp (Forum Supporter) UltraDork
11/10/21 8:24 a.m.
Johnny_at_NineLives said:

is there any way you can not use that overhang bumper?

On the miata's with an air dam, we ditched the overhang. we were able to increase down force 300% with almost no drag increase. 

The issue is I would have to come up with something for cooling (car is a bottom feeder).  That said, it is possible.

sleepyhead the buffalo
sleepyhead the buffalo Mod Squad
11/10/21 9:26 p.m.

Johnny/Stafford can correct me if I'm wrong... but I think the main benefit to what the "get rid of the overhang suggestion", is that the vertical-ish face of airdam moves forward and centralizes the positive pressure forces on the upper side of the splitter/airdam to the furthest moment arm from the CG.  Which means, that you can trim-in more rear downforce to balance.

I expect that Johnny's car... being an "unlimited" time attack build... has a bit more rules latitude than you do.  Although, (and acknowledging my lack of familiarity with c-mod's rules) there might be some room to add a vertical airdam forward, that provides some of the benefits, and gives rise to ducting in to the radiator with a more efficient 1/3-of-radiator area opening that expands to the face.  Preferably, that'd probably include canting the radiator at an angle, so the exit flow from the radiator can be forced more-cleanly out "rules legal sized hood ramps/louvers".... although you can do the same with a vertical radiator, it's just more "difficult" (from the air's perspective).

Gimp (Forum Supporter)
Gimp (Forum Supporter) UltraDork
9/15/22 2:44 p.m.

Still waiting on photos from Nationals, but I saw this one and, at least to me, it seems to show things are working.

The air dam, specifically, normally butts up against the body with at least 3/4" overlap. I'm seeing some daylight.

I'm also seeing zero slack in the cables, and I know there was a little.

 

 

Nothing much more to add. I just thought it was neat.

1 2

You'll need to log in to post.

Our Preferred Partners
JFzyE3zyXIDe2z3NowGGlUE24jYiMieJB0rPSotco7IP77MWwNMQy304NTlSXH1V