mdw1000

Since it seems that a big part of the slowness of the 4AT is the tall gearing, would it be feasable to put the 6 speed AT into the 4 port autos? If so, how much does a 6 speed tranny costs?

Has anyone actually driven both the 4AT and 6AT? Is the 6AT noticeably faster?

Just throwing out some ideas...

SlayerRX8

Well the 6MT is a 6 port motor too, so that's also a difference between the 4AT and 6MT. If you want a fast auto, boosting is your only option. Otherwise, get a manual.

I'm not really sure about swapping the gears, but I can't see it being too cheap. Who knows? I'm sticking with the 4AT gears so I have traction when I get more power.

dillsrotary

reread the post, he wants to swap a 4 speed auto for a 6 speed auto.

as for is it do able? it probably is, but the money wouldn't be worth it for the gains (if any really)

i say keep patience and hope, there might be a supercharger for the auto in the future.

Eddie13

I have an 06 AT. Never drove an 05 auto but after hearing all the problems the 04 and 05 autos had and the increase in HP of the 06, I thought it was a logical choice.

When I drive mine in Manual mode it moves quite well.

Clavius

Best bet would be try to find a junkyard 6speed a/t rip the tranny and ECU out. Also having really good knowledgable friends would be a bonus. Paying someone outa your own pocket wouldnt be worth it really. I'd guess you'd be looking at 5k+ for the swap if you did it through buying from Mazda. I could definatly be wrong bout the ECU being needed but I'd imagine it would have the info for electornicly switching gears from the paddle shifters and such. In the future if my tranny ever dies I'd definatly look into this

SlayerRX8

Yeah, I know his intentions. I read the post. He compared the speed of the 4AT to the 6AT and I responded that there are other factors at play than just the gearing.

Then you rephrased everything else I said.

red8gt

i decided to pay off the car now and save up some cash and get the SC when it finally comes out... going to cost about 5g's+, but hopefully we'll get about 75hp out of it

mdw1000

OK, guys. Thanks. That's pretty much what I thought. But figure it didn't hurt to ask.

I'm thinking the petitt SC will probably be the best way to go, but I'm not sure yet.

SlayerRX8

Personally I think Hymee's kit will be of higher quality, but it seems Pettit will finish first. Still, we can't know how the final product will behave in the field on everyone's car. I'll give each kit a fair chance.

Mazmart

iTrader: (12)

I did a quick check (Not even comprehensive) and the parts alone would exceed $15k. Thought it would be interesting to know.

Paul.

rotarygod

I personally don't think a swap to a 6 speed auto transmission would be worth the effort. Not even if you could get the parts for cheap.

invasion08

iTrader: (7)

yeah you need the 6 port engine, six speed auto tranny and new ecu

Clavius

True but as Jay Leno once said "I'm part of the More Money than Brains Club.. I'm even the President." Someone will do it eventually 'cause of that fact lol.

RotaryP7

Hmm.. Doesn't the 6 spd AT have a higher top speed? Just guessing here. I have a 6 spd AT btw.

+15 hp is what you get. Is there a big difference..

mdw1000

^ Plus you get shorter gearing. I wonder if that makes a big difference down low - anybody who has driven both have an opinion?

ZooTender

Hmm, now I'm curious. May go drive the new 8. I have an 05 and was trying to wait for the 06 but it took so long to come out! The lease on my last car was up in June 05 I actually borrowed a car for a few months waiting for the 06 model to come out. Finally in Sept I bought the 05. Wasn't it well into 2006 before the 2006 model finally came out?

Agent of Chaos

I recently upgraded froma 2004 Auto to a 2006 Auto. Going to the 06 I could definitly tell it was putting out a few more horses, and fast acceleration was definitly smoother. Not being real tech savy on the renisis engines (yet) I can really only geuss that the extra the extra horse are coming from the extra 2 ports. If it were possible to put a 6spd auto on a 4 port engine, I would venture a guess the only real benifit would be smoother, maybe a little faster acceleration. As I stated on another forum about my upgrade...

therm8

Mathematically, the 6spd's will be marginally faster. The gearing is a little better and it makes a bit more peak power, but low end power is lower and the final drive is taller. You might see 2 to 3 tenths of a second. Nothing to swoon over. I didn't like the 6spd transmission when I test drove the Mx-5. It was slow to downshift, and getting to a proper passing gear took too many shifts. Instead of dumping money into swapping transmissions it'd be better speent on forced induction, where tall gearing doesn't matter as much.

(and (to the above poster) at no point whatsoever will the 4spd redline at 65mph. 47, 81-82, 122-23 for 1st-3rd (fuel cutoff))

Agent of Chaos

therm8: Am I interpreting this statement right?
Fuel Cutoff for 1st is 47mph
Fuel Cutoff for 2nd is 81-82mph
Fuel Cutoff for 3rd is 122-123mph

Clavius

3rd is atleast 126... not that I'd personaly know... ::whistles inocently::

Moon Assad

I found out that the 4 speed is a stronger tranny. I test drove the 6 speed and the down shift was what changed my mind on buying one. Its been a while since but I rember it didnt downshift as early and that caused the car to not pull as hard out of the turns as when mine did when stock. You can drop it into 1st at 30 2nd at 70 and I never looked at the speedometer to see when it drops from 4th to 3rd. I just now that its governed at 126, damit and only tacks at 5500 in 4th. Hmm, remove govener by a flash. and I wouldnt be surprised if its capable of 160 mph.

sosonic

Not worth it, even if you could do it. Buy a used 4AT to save money or buy a new 6AT for possible upgrade value. But, I don't think its worth trying to swap.

1. 4AT would be cheaper to get your hands on.

2. If you go turbo or supercharger, there is nothing a 6AT would have on you. There are also arguments that the 4AT might be faster.

3. If you get the ECU flashed on the 4AT and remove rev and speed limit, again I don't see the 6AT having anything on you.

4. In Japan, the 6AT has only 5 HP more than the 4AT.

5. RAM duct (like one from RB) can be used to help get more air in at higher speed and its a cheap mod.

Its all about the tranny.

I don't think Mazda pushed the limits enough with the 6AT to make it such a big advantage. The limit still seems to be the tranny. The 6AT tranny is 7,500 rpm and the 4AT is 7,200 rpm.

If Mazda pushed the tranny on the 6AT to 8,000 to 8,500 rpm than you would see something. I would be interested in somebody with a 6AT that gets the ECU flashed (cut rev limit) and install a ATF cooler. I wonder if their performance numbers would be closer to the manual.

Well is there any 6AT guys that have tried it (ECU flash (rev cut) and ATF cooler)???

The 6AT makes sense from a Mazda production point of view. Basically, the automatic and manual are the same engine and have close configurations. You get the 2nd oil cooler, different gears, etc... If Mazda ever pushed the limit on the AT tranny, I think people would have a whole new view of the RX-8 Auto.

zeblien

Ya, you can keep the car in first @ 27 mph and will get a nice boost to the end of 1st into 2nd gear. Very fun around corners and such

Rotarx8

How did you end up taking off the governer exactly bro? I've been trying to find out fpr a good minute and have had no luck, id appreciate it if u would explain it to me

loewenm

My friend, Moon posted this in 2006. Necro City, bro! Who knows if he still remembers?!