Notices
RX-8 Racing Want to discuss autocrossing, road-racing and drag racing the RX-8? Bring it here. This is NOT a kills/street racing forum.

RX-8 weak points?

Thread Tools
 
Rate Thread
 
Old Nov 3, 2009 | 06:11 PM
  #1  
garyk's Avatar
Thread Starter
Registered User
 
Joined: Sep 2009
Posts: 5
Likes: 0
From: Verona,VA
Question RX-8 weak points?

I'm seriously considering an RX-8 as an autocrosser and occasional street car. The reason being that I'm looking for something I can just drive to an event in, compete, and go home with minimal fuss. Don't feel like constantly changing tires and/or trailering any more. To me, that means something in the ST classes. I've come down to three choices: STX RX-8, STX BMW 3 series, and ST (spec) 89 Civic.

Having owned a couple 3rd gen RX-7's in the past, I can appreciate the strong points of a rotary powered Mazda. What I'm worried about is durability. Is there anything in particular that is a weak point? Things above and beyond expected consumables (tires and brakes), and typical maintenance? For example, wheel bearings that last a couple events, bushings that randomly fail, transmissions that like to go boom.

I've tried searching, and haven't found anything. But since I don't know what kind of failures might be common, I don't know what search terms to use, and don't feel that I'm getting the full picture that way. Any input is appreciated.
Reply
Old Nov 3, 2009 | 06:30 PM
  #2  
chiketkd's Avatar
Row faster, I hear banjos
iTrader: (5)
 
Joined: Jul 2003
Posts: 2,217
Likes: 2
From: Charlottesville, VA
Hey Gary, it's Chike from the Blue Ridge Region.

I've run my car in B-stock for two seasons with 1 co-driver the first year, and 2 co-drivers the 2nd year and had no breakages whatsoever. I'm still on the factory clutch, engine, transmission, etc. Just be sure to do regular maintenance, and switch out the trans and diff fluids to a reputable synthetic product like Redline, Pure power, etc.

If you want to ask me anything offline about the car, e-mail me at chiketkd 'at' yahoo 'dot' com

Last edited by chiketkd; Nov 3, 2009 at 06:32 PM.
Reply
Old Nov 3, 2009 | 06:31 PM
  #3  
RyansRx8's Avatar
Brettward is/has a G
 
Joined: Nov 2008
Posts: 699
Likes: 0
From: St. Louis, MO
torque
Reply
Old Nov 3, 2009 | 06:40 PM
  #4  
garyk's Avatar
Thread Starter
Registered User
 
Joined: Sep 2009
Posts: 5
Likes: 0
From: Verona,VA
Originally Posted by chiketkd
Hey Gary, it's Chike from the Blue Ridge Region.

I've run my car in B-stock for two seasons with 1 co-driver the first year, and 2 co-drivers the 2nd year and had no breakages whatsoever. I'm still on the factory clutch, engine, transmission, etc. Just be sure to do regular maintenance, and switch out the trans and diff fluids to a reputable synthetic product like Redline, Pure power, etc.

If you want to ask me anything offline about the car, e-mail me at chiketkd 'at' yahoo 'dot' com
Hi Chike...I saw that you're pretty active on this forum and thought I'd try to contact you. Thanks for the input, I'll be in touch.
Reply
Old Nov 3, 2009 | 06:43 PM
  #5  
garyk's Avatar
Thread Starter
Registered User
 
Joined: Sep 2009
Posts: 5
Likes: 0
From: Verona,VA
Originally Posted by RyansRx8
torque
Yep, torque is nice. But the lack thereof should make parts of the drivetrain live long, happy lives I hope.
Reply
Old Nov 3, 2009 | 09:36 PM
  #6  
TeamRX8's Avatar
Registered
iTrader: (25)
 
Joined: Apr 2005
Posts: 26,932
Likes: 2,139
Engine compression sealing
Transmission
Clutch disc
Reply
Old Nov 3, 2009 | 10:17 PM
  #7  
MagnusRacing's Avatar
Registered
iTrader: (2)
 
Joined: Mar 2009
Posts: 332
Likes: 9
From: San Diego, CA
Overall the RX-8 is very reliable for track work.

The transmission on the 2008 and earlier model can sometime be a bit delicate but I've beat on mine for some time now with no problems.

Engine temps can be an issue at hot racetracks - would not be a problem with autocross.

Having come from a couple 3rd generation RX-7s myself I can assure you that the RX-8 is loads more reliable and much less expensive to run. It's not quite a Miata but still really good.
Reply
Old Nov 4, 2009 | 06:42 PM
  #8  
mwood's Avatar
Registered
 
Joined: Sep 2006
Posts: 1,363
Likes: 0
I'd say the '8 is a pretty well built car, at the price point, and very reliable.

Transmissions are hit and miss...mine ate itself at 7000 miles and was replaced under warranty. Others have had theirs last for the life of their ownership...luck of the draw or maybe a supplier problem. Having said that, the teams road racing RX8's are known to keep a larger than normal number of spare transmissions in the truck...
Reply
Old Nov 4, 2009 | 07:46 PM
  #9  
garyk's Avatar
Thread Starter
Registered User
 
Joined: Sep 2009
Posts: 5
Likes: 0
From: Verona,VA
Hmmm, the potential for trans problems does worry me a little bit. I'll have to research that a bit.
Reply
Old Nov 4, 2009 | 08:04 PM
  #10  
chiketkd's Avatar
Row faster, I hear banjos
iTrader: (5)
 
Joined: Jul 2003
Posts: 2,217
Likes: 2
From: Charlottesville, VA
Originally Posted by garyk
Hmmm, the potential for trans problems does worry me a little bit. I'll have to research that a bit.
The 2009+ model cars have a beefier 6spd trans that weighs ~20lbs more. There are also revisions to the series II renesis engine that should improve reliability (such as larger oil coolers, 50% higher oil pressure, larger oil pan, larger oil filter, etc).

However, the sum of all of these upgrades is an increase in curb weight, as the 09+ RX-8's weigh roughly 100lbs more than a similarly equipped '04-'08 model...
Reply
Old Nov 4, 2009 | 08:37 PM
  #11  
mwood's Avatar
Registered
 
Joined: Sep 2006
Posts: 1,363
Likes: 0
Originally Posted by garyk
Hmmm, the potential for trans problems does worry me a little bit. I'll have to research that a bit.
Hint: there is a whole section titled "problems and issues" (or something like that) in the Tech section...keep in mind, people don't post unless they've had a problem and then they post often and loudly

The transmission issue is well known, but, as I said, apparently random. If you buy a new '09, as chike said, you have the updated trans, but it you buy used...

If I was going to buy a used RX8 for autocross, I'd buy a car that had already been autocrossed for at least a couple of seasons and not had transmission issues, rather than buy someone's daily driver that has never had the synchros put to the test. As has been pointed out, some of the transmissions seem to do just fine, others notsomuch....

btw, there are at least two well known, solid RX8's set up for autocross currently for sale, including the 2009 Nationals/Pro Finale winning car.
Reply
Old Nov 4, 2009 | 11:20 PM
  #12  
kersh4w's Avatar
Hit & Run Magnet
iTrader: (3)
 
Joined: May 2007
Posts: 6,690
Likes: 3
From: DC Area
transmission
Reply
Old Nov 5, 2009 | 08:24 AM
  #13  
altiain's Avatar
Sparky!
iTrader: (3)
 
Joined: Sep 2004
Posts: 547
Likes: 0
From: East Jesus (Murphy, TX)
Another former FD owner chiming in...

These cars are light years ahead of the third gen RX7 in terms of reliability. However, I'll echo what previous posters have said about the transmission being the only real glaring weak point in the '04-'08 cars (especially since 99% of those cars will still have the full factory 8-year/100k mile engine warranty).

2nd gear was replaced on my car under warranty at ~35k miles. At 60k miles, my transmission whines a little in 4th & 6th, and the 3rd gear synchro is a little notchy until it warms up. However, my car has been a heavily autocrossed car since it rolled off the lot (three full season of National level competition including co-drivers, plus over 100 local events), and it also sees ~1200 track miles per year.
Reply
Old Nov 5, 2009 | 08:41 AM
  #14  
kersh4w's Avatar
Hit & Run Magnet
iTrader: (3)
 
Joined: May 2007
Posts: 6,690
Likes: 3
From: DC Area
lucky bastard.
Reply
Old Nov 5, 2009 | 08:57 AM
  #15  
Huey52's Avatar
Registered Zoom Zoomer
iTrader: (2)
 
Joined: Apr 2006
Posts: 4,089
Likes: 6
From: New England
The ignition is a bit weak as well (easily rectified by BHR system).
Reply
Old Nov 5, 2009 | 12:30 PM
  #16  
TeamRX8's Avatar
Registered
iTrader: (25)
 
Joined: Apr 2005
Posts: 26,932
Likes: 2,139
Apparently the transmission issue is some what user oriented

the OE ignition is fine for NA applications, the top two NA chassis dyno graphs on here were using OE and nobody has ever shown anything other than butt dyno conjecture WRT any improvement. In fact it's a bit annoying to see people posting over and over again in the tech area that this mod is the magic elixer for every known RX-8 ailment. Even the main aftermarket supplier makes no such claim
Reply
Old Nov 5, 2009 | 01:05 PM
  #17  
Huey52's Avatar
Registered Zoom Zoomer
iTrader: (2)
 
Joined: Apr 2006
Posts: 4,089
Likes: 6
From: New England
You are absolutely correct in that the BHR Ignition Solution makes no claims to enhance performance. However (you just knew there was going to be a however), the GMC Yukon Coils and MSD cables are more reliable with better longevity than the OEM. Under prolonged stress (track) they also resist electrical degradation better (somewhat analogous to brake fade wrt uprated rotors & pads). As an EE who has worked in the DoD Reliability & Maintainability discipline I did my own research and assured myself of same before I bought the system. All component data is readily available should others wish to do the same.

Originally Posted by TeamRX8
...
the OE ignition is fine for NA applications, the top two NA chassis dyno graphs on here were using OE and nobody has ever shown anything other than butt dyno conjecture WRT any improvement. In fact it's a bit annoying to see people posting over and over again in the tech area that this mod is the magic elixer for every known RX-8 ailment. Even the main aftermarket supplier makes no such claim
Reply
Old Nov 5, 2009 | 01:23 PM
  #18  
TeamRX8's Avatar
Registered
iTrader: (25)
 
Joined: Apr 2005
Posts: 26,932
Likes: 2,139
I have the data and components too, and for far longer than just about anyone else

again, just conjecture to date, I'll be putting both to a comparison test to see if my hunch plays out
Reply
Old Nov 5, 2009 | 01:29 PM
  #19  
Huey52's Avatar
Registered Zoom Zoomer
iTrader: (2)
 
Joined: Apr 2006
Posts: 4,089
Likes: 6
From: New England
^ Not conjecture per se on my part as I ran the respective component numbers through my Operational Availability (Ao) model just for the heck of it.

But concur that there is nothing like real world data and we look foward to your feedback.
Reply
Old Nov 5, 2009 | 01:45 PM
  #20  
TeamRX8's Avatar
Registered
iTrader: (25)
 
Joined: Apr 2005
Posts: 26,932
Likes: 2,139
Ao - real data = GIGO.


.

Last edited by TeamRX8; Nov 5, 2009 at 01:48 PM.
Reply
Old Nov 5, 2009 | 01:48 PM
  #21  
Huey52's Avatar
Registered Zoom Zoomer
iTrader: (2)
 
Joined: Apr 2006
Posts: 4,089
Likes: 6
From: New England
^ my equations are somewhat more complex, but ....
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ouimetnick
Series I Tech Garage
25
Sep 14, 2023 01:44 PM
drebbrnator
Series I Trouble Shooting
11
Dec 27, 2018 07:02 PM
motohegg
RX-8 Discussion
2
Aug 23, 2015 08:14 AM



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


All times are GMT -5. The time now is 06:01 PM.