Notices
Series I Tech Garage The place to discuss anything technical about the RX-8 that doesn't fit into any of the categories below.

Do I really need the engine undercover?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 06-15-2011, 09:52 PM
  #1  
Registered User
Thread Starter
 
wozzy941's Avatar
 
Join Date: May 2011
Location: New Jersey
Posts: 11
Likes: 0
Received 0 Likes on 0 Posts
Do I really need the engine undercover?

Do I really need this?

https://www.rx8club.com/rx-8-parts-sale-wanted-44/wtb-rx8-engine-undercover-195188/#post3519896

We have a little group of RX8 owners and 3 of them don't have it. They just took it off and said that they really don't need it. In your opinion, do I really need it? Do you have it on? I really do not want to spend 140 dollars on something I don't need.
Old 06-15-2011, 09:56 PM
  #2  
Modulated Moderator
iTrader: (3)
 
dannobre's Avatar
 
Join Date: Feb 2004
Location: Smallville
Posts: 13,718
Received 334 Likes on 289 Posts
The undertray is what directs the air to go through the rad instead of under it

How well do you think the rad is going to work with less air going through it?

Thought so

It also keeps the rocks and larger stuff from taking out your condenser and radiator

Last edited by dannobre; 06-15-2011 at 10:15 PM.
Old 06-15-2011, 10:13 PM
  #3  
Big Machine
 
MBTwenty's Avatar
 
Join Date: Apr 2011
Location: Columbia, Kentucky
Posts: 118
Likes: 0
Received 0 Likes on 0 Posts
I don't have one.
Old 06-15-2011, 10:14 PM
  #4  
SARX Legend
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
^ Dan is the man, listen. Not to mention you will have no AC or radiator if a big enough rock pebble (or something else) bounces up.

It really is a stupid question.
Old 06-15-2011, 10:15 PM
  #5  
SARX Legend
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX

Originally Posted by MBTwenty
I don't have one.

Yeah, people drive around without front bumpers too.
Old 06-15-2011, 11:21 PM
  #6  
Registered
 
sauceyI986's Avatar
 
Join Date: Jun 2006
Location: Laveen,Az
Posts: 855
Likes: 0
Received 0 Likes on 0 Posts
It does affect air flow without it the engine will try to over heat
Old 06-16-2011, 03:02 AM
  #7  
Big Machine
 
MBTwenty's Avatar
 
Join Date: Apr 2011
Location: Columbia, Kentucky
Posts: 118
Likes: 0
Received 0 Likes on 0 Posts
I've driven 600 miles straight without it. I rebuilt my car and never got around to buying it after all the body repairs. Works fine though, never over heated.

Last edited by MBTwenty; 06-16-2011 at 03:48 AM.
Old 06-16-2011, 05:42 AM
  #8  
Stock - O - Licious
 
slvrmzdrx8's Avatar
 
Join Date: Apr 2011
Location: Colorado
Posts: 224
Likes: 0
Received 0 Likes on 0 Posts
Why remove it is my question, understand if you dont have one after a collision or something and cant afford it, but if you have one, why take it off?
Old 06-16-2011, 05:43 AM
  #9  
Registered
 
neXib's Avatar
 
Join Date: May 2008
Location: Norway
Posts: 635
Likes: 0
Received 1 Like on 1 Post
It's funny how the "home expert" has these ideas of "useless parts". Why do you think Mazda would put something totally unnecessary on the car adding extra weight and cost?

Before you remove ANYTHING, find out what it's for and if it's something you can compromise the plus and minuses of removing.
The following users liked this post:
KeenanR10 (03-24-2021)
Old 06-16-2011, 08:30 AM
  #10  
Not yet famous
iTrader: (7)
 
BRODA's Avatar
 
Join Date: Nov 2007
Location: MA
Posts: 565
Likes: 0
Received 5 Likes on 5 Posts
Yes you need it.
Old 06-16-2011, 08:46 AM
  #11  
U.S Army
iTrader: (6)
 
Domenico's Avatar
 
Join Date: Jun 2010
Location: Ohio
Posts: 210
Likes: 0
Received 0 Likes on 0 Posts
Ha love these threads. It's a good question to ask so everyone knows, but he is right. Mazda wouldn't put that there if it didn't serve a purpose.
Old 06-16-2011, 09:30 AM
  #12  
#50
 
bse50's Avatar
 
Join Date: Nov 2007
Location: Caput Mundi
Posts: 7,521
Received 10 Likes on 10 Posts
Cooling aside it also has some aerodynamic properties.
Slap 4 suspension potentiometers on your car and see what happens at 120mph with and without it.
The following users liked this post:
KeenanR10 (03-24-2021)
Old 06-16-2011, 11:04 AM
  #13  
Registered User
iTrader: (1)
 
Reaver's Avatar
 
Join Date: May 2011
Location: Indiana
Posts: 75
Likes: 0
Received 0 Likes on 0 Posts
I agree they put it on there for a purpose, but I just drove from TN to northern Indiana without one with no problems (I do have a dual core mishimoto radiator). Just saying, do you absolutely need it, no, but you have to understand you're taking some risks (stones doing damage, etc like others mentioned).
Old 06-16-2011, 11:42 AM
  #14  
SARX Legend
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
Get on the track or do multiple back to back autox runs and you will see just how necessary it is.
Old 06-16-2011, 12:07 PM
  #15  
Phone Booth'd
iTrader: (4)
 
fuztupnz's Avatar
 
Join Date: May 2009
Location: Cincinnasty
Posts: 2,441
Likes: 0
Received 0 Likes on 0 Posts
This argument is still going?

I'm gonna join the "You need it" camp.

Dude with the mishimoto, you should read up on the horor stories of not sealing off your radiator for proper air flow.
Old 06-16-2011, 12:25 PM
  #16  
Registered Zoom Zoomer
iTrader: (2)
 
Huey52's Avatar
 
Join Date: Apr 2006
Location: New England
Posts: 4,089
Likes: 0
Received 6 Likes on 6 Posts
As others have cited the undercover is there for airflow (both aerodynamic and channeling to a/c condenser and radiator and also for some [albeit thin plastic] protection from road debris.

Manufacturers don't include useless parts. It's not good for business, either initial sales or in-warranty maintenance costs.

Can you go without? Of course you can. But why???

btw: I actually added aftermarket condenser/radiator and oil cooler screens as one of my first mod's.
Old 06-16-2011, 02:05 PM
  #17  
Registered User
iTrader: (1)
 
Reaver's Avatar
 
Join Date: May 2011
Location: Indiana
Posts: 75
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by fuztupnz
This argument is still going?

I'm gonna join the "You need it" camp.

Dude with the mishimoto, you should read up on the horor stories of not sealing off your radiator for proper air flow.
I've actually got the undertray at my parents house, it's got a few breaks in the plastic though (I heard it can be plastic welded?), I'm planning on putting it back on but for a week or two I think I'll be alright without it.
Old 06-16-2011, 02:35 PM
  #18  
SARX Legend
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX

Originally Posted by Reaver
I've actually got the undertray at my parents house, it's got a few breaks in the plastic though (I heard it can be plastic welded?), I'm planning on putting it back on but for a week or two I think I'll be alright without it.

3M Gorilla tape works wonders.
Old 06-22-2011, 11:29 PM
  #19  
Apokalypse Rayne
 
Apok777's Avatar
 
Join Date: Jun 2011
Location: Around the Cincy area
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Gorilla tape? I've heard of Gorilla glue... which is like super glue on steroids. Gorilla tape must be like duct tape on steroids then, yes?
Old 06-22-2011, 11:32 PM
  #20  
SARX Legend
iTrader: (46)
 
9krpmrx8's Avatar
 
Join Date: Jan 2007
Location: San Antonio, Texas
Posts: 33,784
Received 452 Likes on 366 Posts
TX

Originally Posted by Apok777
Gorilla tape? I've heard of Gorilla glue... which is like super glue on steroids. Gorilla tape must be like duct tape on steroids then, yes?

Yep, pretty much.
Old 06-23-2011, 01:09 AM
  #21  
Needs Boost!
iTrader: (5)
 
dmedz8's Avatar
 
Join Date: Jul 2010
Location: Lincoln, CA
Posts: 828
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by 9krpmrx8
Yeah, people drive around without front bumpers too.
I am guilty of this
Old 06-23-2011, 04:12 AM
  #22  
FWD specialist
 
MarkLinRacing's Avatar
 
Join Date: Jun 2011
Location: Taiwan
Posts: 10
Likes: 0
Received 1 Like on 1 Post
The undertray is not 'necessary' but is good to have.

I would choose to keep mine for 2 main reasons.

a) It forces air through radiator aiding in it's efficiency. You should see how well intercoolers perform when you have a sealed off duct going towards the intercooler (seen this on my friend's highpower FC RX7, cooling the intercooler with water during dynoing did very little for power).

b) It smooths out the air flowing underneath the car for better aerodynamics. Turbulence under the car causes lift.
The following users liked this post:
KeenanR10 (03-24-2021)
Old 06-23-2011, 05:02 AM
  #23  
Zoom Frickin Zoom
 
Sephitrask's Avatar
 
Join Date: May 2010
Location: Jacksonville, Fl
Posts: 408
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by MBTwenty
I've driven 600 miles straight without it. I rebuilt my car and never got around to buying it after all the body repairs. Works fine though, never over heated.
Do you have gauges? If so, I am amazed (and speculative) that you stayed within safe levels. If not, you don't know anything except that you didn't suffer mass cooling system failure, which is all the stock gauge is going to tell you. it has four marks: cold, normal, one more notch (about the middle) and "oh ****".
Running the car without this tray seems insane; your radiator might as well be pointed at the ground, so unless your local roads get swept every day and are debris free, your playing russian roulette every time you drive.
Old 06-24-2011, 12:19 AM
  #24  
I HATE SPEEDBUMPS!
 
monchie's Avatar
 
Join Date: Nov 2007
Location: Las Vegas, NV
Posts: 8,549
Likes: 0
Received 7 Likes on 6 Posts
Just put it and get this thread over with.
Old 06-24-2011, 03:01 AM
  #25  
Apokalypse Rayne
 
Apok777's Avatar
 
Join Date: Jun 2011
Location: Around the Cincy area
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
I never really thought about it being used to direct air. I just thought it was there to look cool lol. All these points, though, are very good and I am definitely keeping mine on. What the rest of you do is up to you lol.


You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Do I really need the engine undercover?



All times are GMT -5. The time now is 12:52 AM.