Notices
Series I AT-Specific Performance Mods Discuss engine and transmission modifications for your AT equipped RX-8

Here's why the AT engine has less power potential than the 6MT

Old Apr 26, 2004 | 07:25 PM
  #26  
AlexCisneros's Avatar
Registered User
 
Joined: Nov 2003
Posts: 1,223
Likes: 1
From: San Antonio, TX
ok, so using a turbo would not help. Now that doesn't rule out forced induction.

Granted the 4 port will never match the 6 port in volume and therefore power... But wouldn't a positive displacement blower increase power significantly?
Reply
Old Apr 26, 2004 | 07:57 PM
  #27  
RotorMotor04's Avatar
RX-8 "SE3P"
 
Joined: Apr 2004
Posts: 269
Likes: 0
From: Florida Gulf Coast University
Sure it would increase power, but some internals would have to be beefed up to withstand the boost, such as apex seals. Probably not worth it on an auto if you ask me.
Reply
Old Apr 26, 2004 | 08:39 PM
  #28  
rotarygod's Avatar
Thread Starter
Registered
 
Joined: Apr 2003
Posts: 9,134
Likes: 26
From: Houston
You can still add a turbo or a supercharger and still get some nice performance. You can turbocharge a lawnmower engine! The 4 port engine will be fine. You just don't have near the potential of the 6 port engine. If you want a nice power increase, go for it. If you want a full on race car, pick another engine.

You would not have to change anything internally to just add forced induction. This is a very common misconception. The fact of the matter is that if you had to upgrade seals just to use boost, they would be inadequate for nonturbo use as well. Internal pressures aren't that high for low to moderate boost. It is when you run outrageously high levels that strength of parts is an issue. Proper tuning will do more for engine longevity than seal materials.
Reply
Old Apr 26, 2004 | 08:50 PM
  #29  
AlexCisneros's Avatar
Registered User
 
Joined: Nov 2003
Posts: 1,223
Likes: 1
From: San Antonio, TX
lucky for me I have the 6 port engine... I just feel bad for poor 'ol Mike
Reply
Old Apr 27, 2004 | 01:31 AM
  #30  
mikeb's Avatar
100% Italian
 
Joined: Jul 2003
Posts: 9,422
Likes: 0
From: orange,ca
^^^ouch
Reply
Old Apr 27, 2004 | 04:28 AM
  #31  
DOMINION's Avatar
I don't buy Kool-Aid
 
Joined: Apr 2004
Posts: 8,823
Likes: 2
From: Vegas Baby!
So can we sporty people go with a level-10 on the tranny and get a still get a SC?
Reply
Old Apr 27, 2004 | 01:12 PM
  #32  
wakeech's Avatar
mostly harmless
 
Joined: Jun 2002
Posts: 3,440
Likes: 0
From: Greater Vancouver Area, BC
Originally posted by rotarygod
Wakeech: the intake manifold no longer works and now you need a custom built one.
well duh, if you're gonna do something, do it right. fabbing and selling trick parts to the peoples is a good way to make a living.

btw, how is this different for the 6 port anyway?? if the IM for the 4 port would be next to useless in a modified motor, how does the 6 port's stand up in a turbo application??
Reply
Old Apr 28, 2004 | 03:52 PM
  #33  
picosrx8's Avatar
YATYAS-3rd AA BN A CO
 
Joined: Mar 2004
Posts: 241
Likes: 0
From: West Palm Beach, FL
I guess Im just going to have to take my buddy's advice... "If it don't go...chrome it!"
Reply
Old Apr 28, 2004 | 05:23 PM
  #34  
JeRKy 8 Owner's Avatar
Stuck in a love triangle
 
Joined: Aug 2003
Posts: 2,201
Likes: 3
From: Miami, FL
So whois going to bethe first guy onhere to turbo their automatic
Reply
Old Apr 28, 2004 | 05:28 PM
  #35  
mikeb's Avatar
100% Italian
 
Joined: Jul 2003
Posts: 9,422
Likes: 0
From: orange,ca
hopefully me
Reply
Old Apr 28, 2004 | 06:41 PM
  #36  
zmzmrx8's Avatar
Registered User
 
Joined: Jan 2004
Posts: 41
Likes: 0
From: Illinois
I have an auto 8 and am not at all disappointed. I drove both the six and the auto extensivley before buying and most of the difference was probably the lower first gear in the six speed. Absolutely not enough difference to justify shifting gears all the time. If I feel that I need to gearhead there is always the manual mode.
The 6 and the auto weigh very close to the same and by the time you add all that extra crap i.e.(moonroof, leather, etc.) the 6-speed probably weighs more, (which is the way most of the 6-speeds were equipped that I looked at).
The only thing the auto trans might not be able to handle is the 9000r redline. The torque converter would be the weak point. The torque and hp output on the 8 is hardly enough to tear up a tranny.
As for mods for the auto-8, someone just has to develop them.
Be careful where you spend your money.

Just my piece.
Reply
Old Apr 28, 2004 | 07:09 PM
  #37  
MazdaManiac's Avatar
Banned
iTrader: (3)
 
Joined: Oct 2003
Posts: 16,386
Likes: 28
From: Under my car
Originally posted by zmzmrx8
I have an auto 8 ...
...Be careful where you spend your money.

Just my piece.
Be careful indeed.

I suppose if you can't feel the difference, than you should be happy.

However, I can't help but think that you will be mightily dissapointed were you to to attempt to keep up with the 6-speed RX-8 in your auto RX-8 under any circumstance.

They simply don't compare in any way when pushed.

If you add all of the GT suspension and braking goodies to an auto, you might be able to take the corners as well as the 6-speed, but you will be dusted every time on the exits.
Reply
Old Apr 29, 2004 | 02:05 AM
  #38  
rotarenvy's Avatar
Registered
 
Joined: Feb 2004
Posts: 1,802
Likes: 10
From: QLD .au
I can't read jap but the top of this page amemiya.co.jp/rx_8/ it looks like they clame 70ps on the auto.
http://www.re-amemiya.co.jp/rx_8/
Reply
Old Apr 29, 2004 | 02:26 AM
  #39  
rotarygod's Avatar
Thread Starter
Registered
 
Joined: Apr 2003
Posts: 9,134
Likes: 26
From: Houston
Originally posted by wakeech
well duh, if you're gonna do something, do it right. fabbing and selling trick parts to the peoples is a good way to make a living.

btw, how is this different for the 6 port anyway?? if the IM for the 4 port would be next to useless in a modified motor, how does the 6 port's stand up in a turbo application??
LOL! The manifold for the 4 port would only be useless if you enlarged the ports and the runners to the point that they were much larger in area. You don't want small manifold runners feeding large engine port runners and ports. If you just did some port work but didn't enlarge the engine runners at all, it would be fine.

Here's the thing about the autos. For you guys that have them and want to turbocharge them, go ahead. The runners are limited in area when compared to the 6 port engines which simply means that you are also limited in max rpm as compared to the 6 port engines. Last I checked you already were. Nothing changes in that respect. You can still easily get the same low to midrange potential as a 6 port engine using forced induction. The tradeoff will be above 7000 rpm where you simply can't go. In reality since you guys will not need the larger turbo of the 6 port engine, you will have the ability to get much greater low to midrange power than the 6 port engines. Combine this with the transmission shift points and this should make you very happy. It will feel like a low end torque monster compared to the 6 port engine. The turbocharged 6 port engine however will feel like a high revving race engine by comparison.

The guys that typically buy the 6 port engines (in the U.S.) do it for the top end and greater overall performance. The people that buy the auto 4 port engines typically buy them for ease of driving around town with the occasional spirited driving. For the 4 port standard owners in other countries, what are you guys thinking? As far as forced induction on the U.S. spec cars, I don't see how both camps wouldn't be very happy with forced induction. Yes they will feel different. Don't they already?
Reply
Old Apr 30, 2004 | 10:38 AM
  #40  
ironmedic's Avatar
Registered User
 
Joined: Apr 2004
Posts: 238
Likes: 0
From: Puyallup, WA
i really wanted a 6 speed but my wife cant drive as stick
we had to settle for an automatic. i dont mind it, i just shift it in manual mode so i have more control. it doesnt feel the same though! im using to racing my 5 speed mustang!
Reply
Old Apr 30, 2004 | 11:54 PM
  #42  
MazdaManiac's Avatar
Banned
iTrader: (3)
 
Joined: Oct 2003
Posts: 16,386
Likes: 28
From: Under my car
Originally posted by JeupRX-8
In normal driving (1-4k rpm), you can't notice a differance, but when you are above that, you notice. But who drives in the upwards of 6k rpm on a normal driving day anyway?
I do. All the time.

The real questions is: who drives at 1k RPM ?!?
Reply
Old May 14, 2004 | 02:20 PM
  #43  
wakeech's Avatar
mostly harmless
 
Joined: Jun 2002
Posts: 3,440
Likes: 0
From: Greater Vancouver Area, BC
Originally posted by MazdaManiac
who drives at 1k RPM ?!?
me, when driving other people's RX-8's
Reply
Old May 14, 2004 | 02:44 PM
  #44  
zoom44's Avatar
Administrator
 
Joined: Jul 2002
Posts: 21,958
Likes: 115
From: portland oregon
i drive at 6k rpm or higher every day. i have also driven it at nearly 1k in traffic. i find my car wont really go along at 1k. more like 1100-1200 @7 or 8 mph in traffic.
Reply
Old May 14, 2004 | 03:18 PM
  #45  
MazdaManiac's Avatar
Banned
iTrader: (3)
 
Joined: Oct 2003
Posts: 16,386
Likes: 28
From: Under my car
At 7 or 8 MPH, you should be in first.
Reply
Old May 14, 2004 | 03:59 PM
  #46  
RXhusker's Avatar
Int-X 293WHP 242TQ :)
 
Joined: Oct 2002
Posts: 1,022
Likes: 0
From: Omaha, NE
All the fun begins at 6k :D Why would anybody drive at 1 to 4k?
Reply
Old May 14, 2004 | 04:18 PM
  #47  
rotarygod's Avatar
Thread Starter
Registered
 
Joined: Apr 2003
Posts: 9,134
Likes: 26
From: Houston
The faster you can acclerate from 1K to 4K rpm, the faster you can get to 6K rpm.
Reply
Old May 14, 2004 | 05:11 PM
  #48  
zoom44's Avatar
Administrator
 
Joined: Jul 2002
Posts: 21,958
Likes: 115
From: portland oregon
Originally posted by MazdaManiac
At 7 or 8 MPH, you should be in first.
thats what i'm saying.
Reply
Old Apr 6, 2005 | 11:50 PM
  #49  
truemagellen's Avatar
Attracts tree branches
 
Joined: Jun 2004
Posts: 5,940
Likes: 3
oh boy
Reply
Old Apr 7, 2005 | 01:51 AM
  #50  
HiTMaNN's Avatar
RX-8s Official Cool Guy
 
Joined: Mar 2004
Posts: 2,150
Likes: 1
From: Vancouver BC
Very nice write up rotary god kudos. Thats why i have put my auto rx8 for sale
Reply

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


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