alnielsen

iTrader: (4)

Isn't ATF also high in detergents? I seem to remember something about putting/running a quart before a oil change.

ArXate

I talk a little more about something related in another thread but I didn't bother to expound here earlier. Statistics by itself means little; rather, it's the reality of the world or the truth of things behind those numbers that one should focus on. Many years ago, I read an awesome study published in Science, one of the two top non-specific science journals in the world. The renown scientists didn't bother to provide statistics and I mentioned it to my advisor. He said, "The earth is round, p < .05." Sometimes to get a dramatic difference or dissociation is so compelling in revealing some truth that statistics is irrelevant or secondary.

So when I mention that all 3 owners on this forum with 150,000 miles primarily cruise on the hwy, I have also NOT FAILED TO CONSIDER the converse or the opposite side of the same coin: the 50 (?) or so owners on this website who do not primarily cruise on the hwy AND can not make it to 150,000 miles or 100,000 miles or even 70,000 miles for that matter. If there is a systematic reason for this dichotomy or dissociation, the sample ratio of 50:3 is sufficient in revealing that reality or truth, whether it's that premix brings about other problems that can kill a rotary engine or whether it's cruising at a constant speed is less stressful on an engine.

Let's put it another way. Let's say the reality is that something about the design of the renesis makes it extremely difficult to get past 70,000-100,000 miles. If so, then we might expect two observations. First, most of the dead engines die below 70,000 miles or so and were not driven primarily on the fwy. Second, very few make it to 150,000 miles or even 100,000 miles and most who do are fwy cruisers. And this is what we see with the 50:3 ratio. Although the 50 doesn't tell us the percentage who did fwy cruising vs. city driving, the ratio is about the compelling difference between the two numbers rather than the sample size of each group.

BTW, any statistics buffs may have thought about a third observation: Among fwy cruisers, what percentage gets to 150,000 miles? This is irrelevant if the reality of this engine is that it is simply unlikely to survive to 150,000 miles regardless. Thus, the relevant observation is: Of the engines that make it to 150,000 miles, how many are fwy cruisers (observation #2 above)?

So back to the specific topic with MM and Razz. Yes, maybe it's extremely difficult for the renesis to reach 150,000 miles regardless of how you drive or what you do or add, but if you're going to make it, your best shot is by fwy cruising.

shaunv74

That entire post is about proportions and not statistics.

Let us know when you figure out your null hypothesis, confidence interval, and error band. Then we can start doing some appropriate testing to determine the statistical validity of whatever imaginary sample you are talking about.

Statistics aren't irrelevant. They are math. The way they are commonly abused and misunderstood make them useless. As in your example above.

Albmw

I read somewhere that about 270,000 series 1 RX8's have been sold around the world since 2004.

I like this comment from another website:

"Been working on rotaries for over 25 years and never heard of this implosion comment. Usually it’s a driver error. Lack of maintenance or over rev that kills them prematurely.

Sorry that such fine powertrains get in the ham fisted hands of those that can afford, but not appreciate or manipulate properly. They must have problems like the gum and walking thang".

robrecht

What was the "implosion" comment that this person was responding to?

Are you trying to say that the high Renesis failure rate is due to poor maintenance and over-reving???

Flashwing

I cannot see failures due to over-reving of the motor. Many of the RX8 owners I've had the pleasure of knowing come in two flavors. They either drive the car like they stole it or they baby the hell out of it. I've heard a few instances of "I never beat my car" from those who have had engine replacements.

I've never heard of anyone having serious compression loss who said "well, I drive the **** out of it so it was only a matter of time."

alnielsen

iTrader: (4)

I've had 3 engine failures. None of them made 20k miles. All were maintained by the dealer, so they were authorized for warranty. I had one over-rev on a bad downshift during that time.
This 25 yr rotary mechanic apparently doesn't own a Renesis engined car. Otherwise, He would have known first hand the problems with the engine.
My RX7's never had this problem. Even as race cars.

mysql101

I own a diesel now. Diesel going to ultra low sulfur has reduced the lubricity of the fuel. The HPFP is lubricated by the fuel alone, so the lubricity of diesel is important.

As such, some people premix with additives ...

Here's an interesting test you guys might want to read:

http://www.johnfjensen.com/Diesel_fu...itive_test.pdf

At the bottom of the test is the MMO results. It actually reduced the lubricity of the fuel...

Albmw

I try to be aware of who is sponsoring these studies!

Albmw

just checking other websites and RX8 owners clubs, other 30yr rebuild owners, racing engines as well, tell the same story, in different ways. Poor maintenance, experimentation and abuse basically. Added to this was the development in the "cleaner" less polluting oils and fuels, which generally meant lower metal lubricating agents for fear that they may damage the CAT.... Don't shoot me, I'm just the messenger!

I would have changed dealer,..... which one was it?

mysql101

You think it's a big anti-mmo lobby group??!

ArXate

To put it nicely, you are confused.

alnielsen

iTrader: (4)

Continued discussion of my engine failures would take this off topic. If you really want to discuss it. PM me.

swoope

iTrader: (5)

i have been playing catch up here lately..

i do have a comment on a good side effect from my mmo experience to share with you at rr! and about 2k questions.

beers