RIWWP

iTrader: (2)

The speed limiter for the AT is set to 125mph.

The SCCA Autocross rules (which most autocross organizations use) dictate that courses should be designed to limit speeds to no more than about 60mph.

So I'm not sure what problems you would have with the speed limiter while at autocross.

maxchao

iTrader: (2)

Which region is that autox? That's the one i need to go to.

asostre

:O I did not know there were limits for SCCA, however there are not a whole lot of official events down here. All of the ones I've been to are not all that regulated and unofficial. They also have quite a few straights. Though I suppose it may be better to call them track events/days because its not set up like traditional autox. My mistake guys!

asostre

So at what level is the coolant full? The coolant warning comes on randomly and I want to make sure the coolant is topped off rather than assume its the idiot light (coolant sensor is faulty.)

van

iTrader: (2)

I have my 4AT set to 9000 RPM's + speed limiter removed via MazdaManiac Tune.

MM's base calibration sets it to 8500 by default. I was told the 4AT stops making power at 8300 RPM's, with no performance increase beyond that. Although at 9000+ it sounds like an F1.

The side effects - more wear on your transmission. Although Phil's 8 Petitt SC 4AT is set at 10,000 RPM's with stock tranny, and I believe it's still running strong.

asostre

How long has yours been at 9000? And interesting about the 8300. I had no clue about that. Also thanks for the info its very helpful!

van

iTrader: (2)

For over a year now, with no problems. But I don't always redline it 9K everyday. I usually just take to 8500 or slightly above.

Slintx

How normal is 12mpg for street?
I know the rx8 has terrible mileage, but that's like a full 4 mpg below what mazda reports.

sweatr

Not a new owner but part of the title is safe question and answer thread right?. Question: Is there any potential damage to my 8 if i constantly rev it up to the rev limiter to the point the car sumbles at the pre set RPM rev limiter setting?. I ring the rev limiter bell several times every time i drive it. If there is potential problems i can back off on RPM just short of the car stumbling. Just wondering. seemed like a good place eto ask to keep all the haters who live here from attacking . Thx.

RIWWP

iTrader: (2)

The stumbling is the rev limit fuel cut.

There are many who will tell you that you can do damage to the engine and to back it off to where you just hear the beeping tone at. The problem lies with heat and potential and unknown rotor unbalance that can make the tips contact the housings.

RIWWP

iTrader: (2)

Have you read the new owner's thread?

Gas Mileage:

The reality is, a healthy RX-8 will get 17-18mpg city, 22+mpg highway. But 'healthy' means completely healthy: healthy coils, wires, plugs, O2 sensors, carbon free engine, good compression, healthy cat (or no cat), good transmission/diff fluid, no vacuum leaks, clean MAF, clean ESS. Let even one of these slide, and your mileage WILL drop, and it will drop fast. If you believe that RX-8s simply can not get this mileage because you have never seen it, then there is only 1 person to blame, and that is YOU. If you don't get this mileage, then there is something wrong with one of the above points. Or with your foot. Your right foot can make the mileage drop quite a bit as well. And I don't mean granny driving as the answer to good gas mileage. Smoothness is more important than speed. Smooth and fast is better mileage than unstable and slow.

People also tend to point at it being a 1.3L engine, and assume that a 240/238/232 hp rotary "2-stroke" engine is as efficient as a 1.3L 4-stroke piston engine (which is probably in the 70-90hp range). This simply is NOT the case.

So if you can't get this mileage, start poking around for what is wrong.

maxchao

iTrader: (2)

One thing I don't get is that why is Rx-8 rated as 1.3L. I think at one time I did a calculation based on the number of ignition per crank shaft rotation and it makes more sense for it to be rated at 3.9L...Maybe I didn't do that math right...

RIWWP

iTrader: (2)

1.3L is the actual physical displacement of the engine. It's "rated" that because that is what it is.

Racing organizations and some emissions regulations increase it's "effective" displacement to either 2.0L, 2.6L, or 3.2L, based on however that organization decides to penalize 2-stroke motors for not wasting every other stroke.

It doesn't change the fact that it is still a tiny 1.3L engine in physical displacement.

TDC is the full compression mark, and BDC is the full expansion mark. For a rotary, each face is calculated from similar points of greatest expansion and greatest compression, and I believe that volume is then multiplied times 3 for a single rotor's displacement, and times 6 for the entire engine.


Ignitions per crankshaft rotation has nothing to do with the engine size.

For example, how would your ignitions per crankshaft rotation change the displacement of these two engines:
- 6.2L V8 (Corvette)
- 2.4L V8 (Formula 1)

They are both V8s, and both presumably have 1 ignition per cylinder every other crankshaft rotation, so at 6,000rpm, they are both firing 3,000 ignitions per minute, or 375 per minute per cylinder. Dramatically different engine sizes however.

sweatr

Good info. Thx.

paimon.soror

iTrader: (15)

I am asking this on behalf of sweatr:

How can i create a signature on this forum that has a pic of my car so I stop senselessly attaching pictures to my posts? I know I am doing it wrong, but I just dont know any better.

maxchao

iTrader: (2)

I see. I was trying to use the number of ignition per rotation as the 'effective multiplier' for two stroke engine, since in two stroke engine ignition happens twice as frequency...

In any case, I didn't realize that the 'three' as the number of faces per rotor is counted already. Now it makes sense why this engine is so even small..

ken-x8

[QUOTE]'effective multiplier' for two stroke engine, [/QUOTE

It's not a two stroke, but the multiplier is the same as for a two stroke.

Three lobes per rotor, but the rotor spins at one third crankshaft (er, I mean eccentric shaft) speed. So it comes down to one firing per rev rather than two.

I thought that the biggest exploiter this factor was governments that base tax on displacement, and will tax as if it were 2.6 litres.

Ken

Slintx

Thanks man! I go it checked it out. Looked like after my injector hose came loose the ecu was set to permanently over compensating and was injecting too much fuel. Reset ecu. Now the check engine light is on. My mechanic said that since my injectors were messing up, they dirtied up my new spark plugs. Which I'm hoping is the problem. Gonna go to autozone soon(after a drink) and get the cel read. Car still seems to run fine. I should never have said "finally my cars running perfect" lol.
First attempt at a DIY. Wish me luck

BigCajun

iTrader: (1)

Luck is what happens when preparation meets opportunity.

If you have not changed your coils & wires with your new plugs, now is the time.
DIY, you don't need a mechanic for this if you have any mechanical aptitude.
Save yourself some money, & have the satisfaction of a job well done, & the knowledge that it was done right.
Now I wish you good luck!

Slintx

Find jack stand in car=> completely rusted.
Call dad and ask to use his, he asks what I need it for.
Laughs and refuses to let me use it, said he was doing me a favor from destroying my car.
Ego destroyed. Autozone said its illegal to let me use cel reader also. Welp mechanic time

RIWWP

iTrader: (2)

Um.... some really odd information there.


It certainly isn't illegal. I know not all Autozones will read the code for you. Got any Pep Boys or Advance Auto nearby? They still do it for free.

Alternatively, you can buy a bluetooth OBD2 adapter for $25 to $150 (higher price is generally longer lifespan and/or better communication), pair it to your smartphone, download an OBD2 app, and read that code yourself ... and any code you may ever get in the future on that car or any other.

paimon.soror

iTrader: (15)

It is against the law for them to lend the reader to you. They but like RIWWP said, they most certainly can, do, and advertise that they will read the code for you.

BigCajun

iTrader: (1)

Your dad's faith in you is touching.
o_0
Don't give up so easy.
You can find someone to scan your codes for free if you choose not to get a OBD scan app. & dongle, or don't want to wait to get one.
Invest in your own stands, they will pay for themselves.
Plenty of DIY info here, & plenty of members willing to offer assistance & walk you through it.
It's really not hard to do your own basic maintenance, and you can learn a lot of valuable information about your car.
If you're mechanic is not familiar with rotaries, he may not know how to fix it properly.
Some mechanics will change parts without a clue, & it adds up fast.

Gravey

iTrader: (3)

If you are in the Burlington-Oakville-Hamilton area of the GTA I can read the code for you. I have the forementioned OBDII dongle and iPod touch apps.

Slintx

Thanks for the support guys. I think it was my mistake at autozone, they said it was illegal to lend me the reader. Also I should have mentioned that my mechanic will probably read my code for free. If he says it's the plugs then I guess I'll have to find a jack somewhere and prove my dad wrong. Thank you for the offers, and I wish I could I to you guys instead of my mechanic, but I live in SoCal.
Also, I will definitely look into that Bluetooth adapter. Thank you guys!