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Lets look at expo1's over 100K renesis motor

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Old 05-29-2008, 01:02 PM
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Originally Posted by rotarygod
Since most people in this country change cars every 6 years and average 16,000 miles a year, the engine really only needs to hit about 100,000 miles in it's life. At least from a manufacturers standpoint that's all you need to design it to do.
I know for a fact that at least before, Volkswagens were designed for a 105,000 mile life. Of course, their electrical systems didn't seem to last anywhere close to that!

Originally Posted by rotarygod
It is hot here. I use 5W30 in a first gen RX-7 which is supposed to use 20W50! My motor hasn't fallen apart yet.
Paul's going to get you!
Old 05-29-2008, 01:41 PM
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I'm not against thicker oil by any means. I used to run 20W50 and may go back to it at some point. I've got over 100K on my motor and if it dies, so be it. I'll build another.
Old 05-29-2008, 05:21 PM
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Oil's have improved throughout the years, generally. The last changes are, unfortunately, not related to engine life. The better synthetic 0W30s will run rings around some 20W50 oils in film strength over time. Again, a very good allround compromise for those who want more engine life is a reasonably priced 10W40 like I said much earlier in this thread. Those who believe in the dino oils can just change it more often than those who believe in the top syns, that's all. For those who don't want to stretch that far out of their comfort zone, please I beg you, at least go to a 5W30.

Paul.
Old 05-29-2008, 06:12 PM
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Originally Posted by Mazmart
Oil's have improved throughout the years, generally. The last changes are, unfortunately, not related to engine life. The better synthetic 0W30s will run rings around some 20W50 oils in film strength over time. Again, a very good allround compromise for those who want more engine life is a reasonably priced 10W40 like I said much earlier in this thread. Those who believe in the dino oils can just change it more often than those who believe in the top syns, that's all. For those who don't want to stretch that far out of their comfort zone, please I beg you, at least go to a 5W30.

Paul.
Thanks, Paul. Maybe a few questions will clarify some things for some of us non-experts:

Is the Renesis designed with tighter clearances than previous rotaries to justify the use of today's thinner oils?

Also, are there merits to the arguments of some who point to advantages of thinner oil (only talking about high quality oils here) for better heat transfer at high rpms? Any other advantages?

Finally, given the same high quality synthetic, let's say Royal Purple non-racing SL products, do you see unqualified advantages to 10w-40 or 20w-50 over 5w-30 for street use? Is it just a matter of climate, ie, using thinner oils in colder temperatures for better start-up protection? Or is there a necessary compromise between better bearing protection with heavier oils at the expense of other specific disadvantages.

Thanks in advance!
Old 05-29-2008, 06:30 PM
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does Paul know at what point you should be seriously scared for your engine in terms of engine vacuum... my thread is going without enlightenment so far
Old 05-29-2008, 07:03 PM
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Originally Posted by robrecht
Thanks, Paul. Maybe a few questions will clarify some things for some of us non-experts:

Is the Renesis designed with tighter clearances than previous rotaries to justify the use of today's thinner oils?

Also, are there merits to the arguments of some who point to advantages of thinner oil (only talking about high quality oils here) for better heat transfer at high rpms? Any other advantages?

Finally, given the same high quality synthetic, let's say Royal Purple non-racing SL products, do you see unqualified advantages to 10w-40 or 20w-50 over 5w-30 for street use? Is it just a matter of climate, ie, using thinner oils in colder temperatures for better start-up protection? Or is there a necessary compromise between better bearing protection with heavier oils at the expense of other specific disadvantages.

Thanks in advance!
Exceptional questions:

The bearing clearances have not changed (IMPORTANT).
The thinner oils CAN run cooler, yes.
Both horsepower and fuel economy are mildly enhanced with thinner oils.
I think that the really thin winter rating is especially good for an 'idiot proof' society, in that people who WON'T drive gently at start-up and might get hard on the throttle under load conditions in cold ambient temps with a cold engine will be safe. So that's another positive for thin oils. Then there are the trade-offs because, as Mr Engman loves to state :NOTHING IS FREE. You run the risk of bearing damage that we're seeing on numerous motors we take apart. We've always given up 2 or 3 hp for the bearing benefits. We also believe in optimized oil and water cooling through the right equipment (Radiators and pumps).At this time we don't believe that 20W50 is needed in typical street driving but are opposed to 5W20. Take your pick in between.

Thanks for the sharp questions.

Paul.
Old 05-29-2008, 11:30 PM
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Originally Posted by Mazmart
Exceptional questions:

The bearing clearances have not changed (IMPORTANT).
The thinner oils CAN run cooler, yes.
Both horsepower and fuel economy are mildly enhanced with thinner oils.
I think that the really thin winter rating is especially good for an 'idiot proof' society, in that people who WON'T drive gently at start-up and might get hard on the throttle under load conditions in cold ambient temps with a cold engine will be safe. So that's another positive for thin oils. Then there are the trade-offs because, as Mr Engman loves to state :NOTHING IS FREE. You run the risk of bearing damage that we're seeing on numerous motors we take apart. We've always given up 2 or 3 hp for the bearing benefits. We also believe in optimized oil and water cooling through the right equipment (Radiators and pumps).At this time we don't believe that 20W50 is needed in typical street driving but are opposed to 5W20. Take your pick in between.

Thanks for the sharp questions.

Paul.
Thanks, Paul, that's really helpful.
Old 05-30-2008, 01:16 AM
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Originally Posted by mac11
Not to start an argument, just to bring it to light, it seems there are more unscrupulous OEM's out there doing this than there are that stand up behind their product. Most everyone is looking out more for their bottom lines than for their (future, repeat) customers, so it seems.

Almost every OEM in the US that I know of participates in the wholly terrible practice of putting major warranty decisions in the hands of a single regional corporate rep, who's job is that of an insurance claims agent - mitigate losses.
Because in the end, Mazda is a business and the money they make/save by being thieving little bastards is greater than the money from the extra sales of repeat customers. I don't think mazda intended for the Renesis engine to fail quite as badly as it has though.
Old 05-30-2008, 01:36 AM
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That is mostly a problem with a flawed oil metering system design which they have now corrected.
Old 05-30-2008, 01:43 AM
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Originally Posted by rotarygod
That is mostly a problem with a flawed oil metering system design which they have now corrected.
yeah, the 3rd nozzle. It's on the 09 Renesis 13Bs and the 16X right?

Last edited by FloppinNachos; 05-30-2008 at 02:32 AM.
Old 05-30-2008, 06:42 AM
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Originally Posted by rotarygod
Most FC's were non turbos. A majority of their sales were of the n/a's although there was also a turbo model. Thicker oil was also used in all of the earlier rotaries and none of them were turbos so I'm not too sure what your argument is. All manufacturers have gone to thinner oil recommendations over time. 2 reasons. 1 is that oil technology keeps getting better and 2, thinner is less loss. Not much to you or me but to an entire fleet even a little bit counts.

If manufacturers were so concerned with their reputations, they wouldn't pull out all the stops to use every excuse to try to void warranties. Mazda is terrible about this. I honestly don't think they care about overall long term engine reliability once that reliatbility is outside of their warranty period. What happens after that is your problem, not theirs. Engines don't need to be designed to last forever. They just need to last longer than the average car owner has it. Since most people in this country change cars every 6 years and average 16,000 miles a year, the engine really only needs to hit about 100,000 miles in it's life. At least from a manufacturers standpoint that's all you need to design it to do.
i'm just saying that during the 1st gen rx7's, synth. oil did not exist, i guess, therefore 10W-40's were used, and later on when rotaries got turboed, mazda switched to thicker 15W-50 because the stresses (due to the turbo's) inside the engine were more pronounced than in the earlier engines... but then again Mazmart Paul says the stresses inside modern engines are far higher than in previous N/A applications, so ... ( ....we go back to the weight oil issues)

anyway, Mazda definately know that getting a new customer is far harder than keeping/converting an old/repeating one, so they sure have longevity in mind for the Renesis, because 16X (Renesis II) is coming, so ourselves, the old customers should be happy with the one we have...

i think a lot of the problems regarding dealerships (Mazda corporate image etc.) are down to the fact that the post Y2K customer has far more information available on the Net, so the ignorance of the average Jo the mechanic in the dealership gets a lot more pronounced...

... also a simple customer interaction b/w an (RX8) owner and a mazda employee gets easily broadcasted on the Net, and the collective wisdom of the forums can easily judge/downgrade the whole dealer and the parent company...

it's even worse when an owner might know a particular sth about a problem that the mechanic may not know/understand...

but that's not our problem, that's a problem for the corporations !!!
Old 05-30-2008, 08:25 AM
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Originally Posted by claus
i'm just saying that during the 1st gen rx7's, synth. oil did not exist, i guess, therefore 10W-40's were used, and later on when rotaries got turboed, mazda switched to thicker 15W-50 because the stresses (due to the turbo's) inside the engine were more pronounced than in the earlier engines... but then again Mazmart Paul says the stresses inside modern engines are far higher than in previous N/A applications, so ... ( ....we go back to the weight oil issues)

anyway, Mazda definately know that getting a new customer is far harder than keeping/converting an old/repeating one, so they sure have longevity in mind for the Renesis, because 16X (Renesis II) is coming, so ourselves, the old customers should be happy with the one we have...

i think a lot of the problems regarding dealerships (Mazda corporate image etc.) are down to the fact that the post Y2K customer has far more information available on the Net, so the ignorance of the average Jo the mechanic in the dealership gets a lot more pronounced...

... also a simple customer interaction b/w an (RX8) owner and a mazda employee gets easily broadcasted on the Net, and the collective wisdom of the forums can easily judge/downgrade the whole dealer and the parent company...

it's even worse when an owner might know a particular sth about a problem that the mechanic may not know/understand...

but that's not our problem, that's a problem for the corporations !!!
Well spoken, well expressed. Mazda North American Ops (I know you are in Greece) especially have their work cut out for them; they need to further improve their dealer training on every level, especially in service writers and salesmen. Retention of good techs is another problem (I worked as one and have several disgruntled friends who are still there). The 'Flat rate' system is very flawed and causes them to want to rush to complete jobs rather than put the emphasis on doing the ultimate satisfaction type job. I'm the world's biggest Mazda fan and will do anything I can to help the brand move forward. It hurts to see people upset with the Corporation or the dealer group.
THE ONLY WAY that the rotary engine will ever continue into the future is for every effort to be made to take it out of the quaint novelty position it finds itself in and moved more toward the mainstream (Easier said than done). Rumors and facts of flooding must be a thing of the past, fuel consumption needs to match that of engines making 1.4 times it's power output. Checking one's oil every other fill up is ridiculous (A separate metering tank should have been adapted a decade ago), but alas, I'm getting carried away .

Paul.
Old 05-30-2008, 06:21 PM
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Originally Posted by Mazmart
Checking one's oil every other fill up is ridiculous (A separate metering tank should have been adapted a decade ago), but alas, I'm getting carried away .

Paul.
I had almost mentioned this in the 16X thread, but I didn't. Mazda could easily make this a reservoir similar to other fluid reservoirs out of semi-transparent plastic with the big easy to read full/low lines. It seems like alot of the less technically inclined owners find using a dipstick too complicated for any car though...The big question would be what would their specialty oil of choice be for lubrication, PAO based? Polyisobutene based? It would finally give some standardization as to what is best at lubrication for the apex seal temp range 220-260 C and for deposit minimization.
Old 05-30-2008, 07:01 PM
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Originally Posted by BMonkey
I had almost mentioned this in the 16X thread, but I didn't. Mazda could easily make this a reservoir similar to other fluid reservoirs out of semi-transparent plastic with the big easy to read full/low lines. It seems like alot of the less technically inclined owners find using a dipstick too complicated for any car though...The big question would be what would their specialty oil of choice be for lubrication, PAO based? Polyisobutene based? It would finally give some standardization as to what is best at lubrication for the apex seal temp range 220-260 C and for deposit minimization.

BMonkey,

You and I think too much alike sometimes.

Paul.
Old 05-31-2008, 12:46 PM
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Originally Posted by Mazmart
BMonkey,

You and I think too much alike sometimes.

Paul.
That's a big compliment, thanks Paul
Old 05-31-2008, 12:55 PM
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Originally Posted by Mazmart
Oil's have improved throughout the years, generally. The last changes are, unfortunately, not related to engine life. The better synthetic 0W30s will run rings around some 20W50 oils in film strength over time. Again, a very good allround compromise for those who want more engine life is a reasonably priced 10W40 like I said much earlier in this thread. Those who believe in the dino oils can just change it more often than those who believe in the top syns, that's all. For those who don't want to stretch that far out of their comfort zone, please I beg you, at least go to a 5W30.

Paul.
Paul, which oil would you recommend for someone w/ a turbo/supercharged setup??
Old 05-31-2008, 04:57 PM
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10W40 in a 'special brew' that I will soon mention. Maybe 5W40 in the winter.

Paul.
Old 05-31-2008, 05:30 PM
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Originally Posted by Mazmart
10W40 in a 'special brew' that I will soon mention. Maybe 5W40 in the winter.

Paul.
I like special brews!
Old 05-31-2008, 07:28 PM
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I know --a squeeze bulb could be placed in the seat and everytime the engine needs lubrication you could just bounce on the seat and inject oil!!
(i think i need a day off)
OD
Old 05-31-2008, 08:32 PM
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How about 10W40 mixed with a quart of MMO??
Old 06-19-2008, 11:54 AM
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Excuse me bartender. I would like one special brew ^_^
Old 06-22-2008, 10:22 PM
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I have just read through about 80% of this entire thread. There is some really great info in here.
But of all of the posts that I read, I didn't see one that specifically addressed the question that I have......

I live in San Diego. Summer gets above 100 degrees quite often (105 today). Winter is moderately cold, but nothing at all like the east coast.
I drive my RX8 daily and I don't ever take it to a race track. I understand the importance of not asking too much out of *any* engine until it is warmed up.
The only *hard* driving I ever do is an occasional high rev thrust that's always good for the soul and helps clean out carbon deposits (that's what I tell my wife ).

Basically what I am trying to portray here is that I am just an regular driver that wants to put the right kind of oil in my car and leave it alone.
I'll always make sure it's not lacking, but I'd like to stick with one kind of oil that's best for my situation.

2 questions:
1. If I use regular oil, what kind/grade should I use?
2. If I go with Synthetic, what kind/grade should I use?

note: I am more concerned about quality/long term effects than price.

Thanks!
Old 06-22-2008, 10:35 PM
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1. Castrol GTX 5w-30 or 10w-40
2. Royal Purple 5w-30 or 5w-40 or 10w-40

In your climate, I would probably go with 10w-40.
Old 06-23-2008, 06:49 AM
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Wink

Something I would like to point out. If one were to use 20W-50, which we all agree is a little too much you could always add 5W-20 to thin it out. My car consumes about one quart every 1200 miles and I change my oil every 1500 with good old dino. You will most likely need reciepts for the 5W-20 in the event of warranty work anyway.
Old 06-23-2008, 08:07 AM
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Several of us in Phoenix have switched to 20w-50 using the Sohn adapter with success.


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