Yeah, I got to thinking about it. They usually pull lose from the screws in the front and bend down/back against the ground and tire. In your case they may have actually gotten under the tires which would immediately rip them loose from the rivets.

 

think you are right--then it just continued ripping out the back section and travelling under the car and ripped off my tailpipe shroud.
Surprisingly it did not mess them up so bad they could nt be reinstalled with just a little work.

Dude the secret in my vid---is ---look how little my gearshift lever is moving. Know why?
OD

 

Ooh! Ooh! I know! McMaster-Carr polymer section FTW!

 

Mine too, we just tackled it from opposite ends ....

Installing larger diameter washers under the screw heads along the leading edge of those front shrouds helps a lot too.



.

 

Solution:
1. Scrounge in Box O' Crap.
2. Find shouldered self-tapping screws.
3. Drill 1/8" pilot holes.
4. Secure leading edge of liners.
5. ???
6 Profit!

Clearly the problem is the bottom pulls loose, catches air, and Bad Things™ happen.
Spent the weekend on Summit's Shenandoah Circuit without incident, though it's not a particularly fast track.





These are from the sheet metal frames of first-generation RX-7 storage bins.




The bolt is 3/8" with washers a nylon-insert nut. Also from the Box O' Crap.

 

I have a couple similar sized bolts in mine, but they are further back in your "already pulling loose" hole. They kept my fender liner from getting sucked under my tire a couple weeks ago, but the front edge of the fender liner caught enough air that it was bent down scraping the road. I lost about an inch of material before I pulled over to see what the fuss was all about. With the amount of random bolts and zip ties currently piecing together my undertray, I'm seriously considering replacing all three panels - plus the chin spoiler.

On the other hand, it seems like a lot of money to spend considering I will likely break them again before long.

Another concern I have after spending some time down there: my undertray is bowing down in the center to the point that the foam from my radiator is not pressed firmly against it, and air can slip under the radiator. Has anyone else had this problem? I would take a picture, but I snugged it up with a zip tie temporarily until I can order a new undertray or think of a more elegant solution.

 

well--- i know when 130mph wind on the track gets under it--it will tear through the bolt heads etc. trick is to not allow that air in there to start?
Black duct tape on the seams and over the plastic retainer heads works for me so far.
cant tell its there and if you prep the liner 1st -it will stay there a long time.
On the street the bigger screw heads etc should work OK?
OD

 

so when are you going to change your username to "oldfenderwelllinerdragger"?

 

dam... thats a scary thought!

 

Get rid of that little mud flap. Catches the curbs. When you go off track it catches stones bends back and fucx it up worse than you can imagine.


You fix is not track leagal.

Those screws can back out.

Use a screw with nut and lock tite.

Do the correct job.

How would you like to be on the track and run over that screw?

How would you like to be on the track and have that screw thrown up and break your wind shield.

How would you like to be a motorcyclist racing on the track and go down because of some home made crappy job?

 

1. The flap is not a mud flap. It is an air dam to help create low pressure behind the oil coolers. Best leave them there. I can imagine some pretty bad damage having had two race cars totalled out from under me. Those little things won't do much under the worst circumstances. Maybe if you don't go off track they won't be a problem?
2. My fix is track "leagal" at every track and event I've ever heard of, so I haven't a clue what you are talking about. I suspect you don't either.
3. Those screws will not back out. Track tested and confirmed. They are in an undersized hole in plastic. Ever used a nylock? Same principle.
4. Screw with nut and Loctite will work, best use a couple washers too. This was faster, easier, used what I had on-hand, and works equally well.
5. I did the correct job. Who are you to say, exactly?
6. It would be bad if I ran over the screw on the track. Fortunately, won't be an issue. See #3.
7. You haven't been to the tracks I go to, obviously. Turn 3 at Summit Point main has gravel twice the size and sharpness all over the track. The fast line through the exit of T3 is two wheels in the gravel trap. My windshield is already covered with nicks from flying gravel. That little screw wouldn't do dick.
8. I wouldn't like to crash on a bike. But a) it's not home-made crap just because some Intarweb postwhore says it is, b) tracks are swept clean before every track day, and c) the screws are not going to come out (see #3 again, in case you forgot).

Thank you for your input. Have a nice day.

 

I see this as a legitimate concern for someone that hasn't tried it.
I have known him on here a long time and I don't consider him a post *****.There isn't a need to act like that just because someone questions your methods.

 

I just used a good amount of rivets to keep my fender liners and undetray in place. They will stay there for sure!

 

just an observation with someone that has over 120k miles on the car.

the plastic that all the screws that failed on the drivers side might be fine, but if you took it off once or twice the plastic does droop...

then it does vibrate. wait, how many times have you had that stuff off? really. that might have been your downfall..

i found mine loose on the passenger side. scraping after a silly high speed run, fla usa! dont know why, just think after having the bumper off i missed something.

btw, the LIP covers all the screws that could come loose. and it plants the car at ~ 120ish.

beers

 

This is the route I am going. A bit of a PITA to drill the rivets out if I ever need to remove the under-cover, but probably the best solution.

 

I appreciate your position and I agree those are valid concerns. And I addressed them both.

He didn't just question my methods. That would have been "I don't think this is a good idea and here's why..." Instead, he came in and posted "it's home-made crap!" and "Don't you care about anybody else!?" and "UR doing it wrong!" in such a way that clearly indicates he has little or no idea what he is talking about. That was not nice nor constructive. I think my response was restrained considering the tenor of his post.

 

any screw, nut, bolt can come off eventually. Heck a trackmate of mine lost a ppf nut!
People that track regulary know to check things out during prep and inbetween sessions---not just the lugnuts. Mistakes to happen, things are missed--its only human.
I do look under the front and rear etc between sessions
especially now since I have been affectionaly awarded a permanant "meatball" flag decal on my rear bumper---I like it!
I must have missed something when I looked.
I do agree on the things in front of the wheels. leave them there. Matter of fact I have now reinforced them somewhat as at high speed they had too much give.
Its a good aero feature.

oldmeatballdragger

 

photo of meatball flag, or i wasted my time and you got a red tape tip!

photo! that sould be fun. but as you know how to do video now. simple..

to all. the plastic does get warm. and start to droop.. if you do any work with the bumper you need to check the screws that run below the bumper... the back out easy..

denny.. that silly lip i have. does plant the front end above ~120, and all those screws are out of the air flow!

beers

 

If self-threading screws are illegal an RX-8 would never be allowed on a track in the first place

 

 

whimper----
pldmeatballdragger

 

That previous post was just for my own amusement, but just in case anyone is curious.. Here's my solution (hopefully).

 

I decided to remove the MS front bumper on my new (to me) 8 so I could mount the front license plate properly. Check out what I found when I crawled underneath to remove the lower fasteners...



Time to pull a BRODA and order me some new plastic bits!

 

Fortunately the MS lip is lower than the stock lip, so it probably kept the air from pulling the lip down and tearing it off. Otherwise your first track outing could have been more interesting than it was.

As for the random bolts, that's why I like used cars -- they are like a box of chocolates...

Broda's solution will certainly keep that stuff all together but removing it for service/upgrades will be a bit tedious.

 

^ I thought about that before I added all those rivets, but 1) they are aluminum, and I can drill them out in a matter of minutes 2) I don't think I've ever had the undertray off in all the years I've owned the car, so I don't expect to be removing these panels very often.

Also... I did not really address the main issue, which is tearing where the liner screws to the bumper. I ordered all new fasteners, but the weak link is the plastic around those holes which have a tendancy to rip. I considered reinforcing each hole with some aluminum sheet, but I started to wonder if I was going a bit overboard.