Ever since I did the 'O' ring fix-in-a-bottle I have been running with the undertray removed. I was just wondering how many people remove or run without it, and what adverse affects (if any) one can expect.

By the way, I have put about 1500 more miles on since I did the seal and I haven't had to add a drop of water.
And so far, running just water and the sealer **** has not caused any overheating problems, and that has been with some daytime mid-80's temperatures.
The car seems fine, runs fine.

 

put it on and run cooler. its there for a reason as you will learn real fast. with an upgraded radiator i was running hotter than hell. i forgot to put that back on and seal teh sides of the radiator. now i rarely see above 190 with the fans on
kris

 

i've been running without mine, works fine...

i followed the greddy FMIC instructions for hacking it up, and now it goes from the radiator back, so i don't see the reason why you would even have it on other than to protect hoses

 

The front undertray also smooths the air going under the car for those of us who venture into the triple-digits.....

 

i ran over something the other day
its important
although i guess its a moot point

 

do any of u guys know where i can get a new undertray ever since i installed my new sway bar i noticed there wasnt anything there

 

umm...try a Mazda dealer?

Click on the Mazdaformance link above. They are the online presense of Jeff Haas Mazda in Texas. They have great customer service and very low prices (compared to a traditional Mazda dealer). The other choice would be Ray Crowe at Malloy Mazda in Virginia -- again great service and low prices.

 

You know, you may be on to something.
I ran up to 135 - 140 the other day on the interstate for a brief while, and seemed to notice a pronounced buffeting that I hadn't experienced before.
It WAS very windy that day, and I had attributed that buffeting to the wind, but.......
Mazda NEVER put something non-functional on the FD.
Guess it is time to put the undertray back on!

 

Leave the undertray on. If your running any type of SMIC it helps force air into the duct. With all types of ICs it helps more air get to the radiator rather than just go around it.

 

I dont have mine on after the gerddy install either & I find triple digits just fine and dandy...

 

fact is: it's good to have it there

no it's not necessary but come on it's like 8 or 10 bolts? we've done much tougher **** than that

 

The undertray effectively forces air through the radiator. Without it the air can just pass under it. I ran mine around the neighborhood once just to warm it up without the tray and it got hot very quickly. I definitely would not run without the tray.

Barnd new ones are only $156 if you are a Mazda Competition member. You only have to autox twice a year to qualify, people should get out more

 

yeah, you will lose highway stability if you remove it, which I found out pretty quick.

 

Doesn't hurt to put it back on...One of these days you may be on the hwy and don't have any choice but to run over whatever and it could poke a hole in your rad. Only takes a few more minutes to put it back on so go for it...

FYI, I ran with mine off for a while after installing my FMIC and I honestly believe it does help a bit with cooling...

 

Never underestimate the importance of undercar aerodynamics. Air goes both over and under your car. If you're running a stock bumper then I suggest keeping the undertray since they spent time together growing up in the windtunnel. If you've got an aftermarket bumper then I guess it doesn't matter since your front end aero's are probably pretty goofed up to begin with.

Dave

 

Don't listen to anyone who says its ok to take the undertray off. I have heard a few times that your car can seriously overheat from running w/o one even after as little as 20 minutes. There is absolutely no benefit, only shortcomings, which result from running without an undertray.