staticguitar313

iTrader: (2)

I do ^_^ makes me feel much more safe

Pele

iTrader: (28)

I use Rotella in a couple of my engines. My NA IDI 7.3L V8 Diesel Ford Tow truck... International Harvester engine for obvious reasons, and I used to use it in my Isuzu 3.2L V6 until it started leaking like a seive... Isuzu engines are known for valve clatter when the hydraulic lash adjusters clog up with junk. The high detergent package in the Diesel blended oil is supposed to help solve this.

Link to the article plz.

WTF is zddp?

Monkman33

iTrader: (28)

zddp is the additive that has been decreased in most oils due to environmentalists. It is an extremely effective anti-wear agent. You need to buy some and use it. Or use an oil with high zddp content.

Evil Aviator

That article's technical information is from Red Line Oil, which only produces top of the line Group V synthetic oils. Synthetic oil (Group IV and V) is not comparable to petroleum oil. Synthetic oil has a better temperature range, wear reduction, and friction reduction than a petroleum oil of the same SAE viscosity.

The article does have some merit in that thinner oil may offer better performance for short races, such as autocrossing, hill climbs, drag racing, etc. However, I don't think this relates to normal street driving unless you only drive your car for 1-2 miles at a time.

For a daily-driven RX-7, I think it is better to stick with the manual written by the Mazda engineers. In Florida I used 20W-50 year round due to the hot weather, but in St. Louis I use 10W-40. Castrol GTX is popular because it has shown reduced wear and deposits in engines when they are disassembled for rebuilding. As much as I like scientific psychobabble, actual results matter more to me.

There is also a rotary-specific problem in which the eccentric shaft tends to shear the oil much more than piston engines. This is why you should not go along with the "extended drain interval" advertised by some synthetic oil manufacturers.

It stands for Zinc Dialkyl Dithio Phosphate or Zinc Diaryl Dithio Phosphate, which is an oil additive that helps reduce friction on the valve train of a piston engine. The downside is that it shortens the life of catalytic converters, so the US EPA has gradually reduced the amount of ZDDP in engine oil over the years since the 2Gen RX-7 was last produced. Some rotary engine owners are concerned that the reduced levels of ZDDP may have an adverse effect on rotary engines, but there has been no proof of this so far, and in theory there should be no problem. I do not know of any major rotary-engine race teams adding ZDDP, however their piston-engine counterparts have been using it for about 10 years now, especially in the older style flat tappet engines. The newer piston engines with low-pressure valve springs don't seem to be affected much by the reduced ZDDP levels.

no_more_rice

For good reason. "Gains" isn't the issue, it's protecting your engine! How long have you been on this forum?

These cars average 5-10% fuel dilution. Fact. Fuel dilution reduces apparent viscosity of any oil quickly (it also accelerates internal corrosion and general deterioration of the oil), it can lose at least one viscosity grade within 1000 miles, as proven by UOAs. I'm running Amsoil 20w-50 and have been extremely impressed with it's ability to maintain factory spec oil pressure to 3000+ miles. Mobil 1 15w-50 is toast at that point. Every FD owner should be getting their oil analyzed for viscosity and fuel dilution so they know exactly where they stand, anything else is worthless conjecture/opinion, which summarizes most of these types of threads.

Street or track, most of us drive their cars hard and are on the boost all the time at low 11s AFR, which is a major cause of fuel dilution. Unless you want to change your oil every 1000 miles, running 10w-30 with 5-10% fuel dilution is not advised.

no_more_rice

Good read on the subject

http://www.cambridgeviscosity.com/ar...ndition4.shtml

Fuel dilution can also reduce TBN
http://www1.eere.energy.gov/vehicles...r08_watson.pdf

Mahjik

iTrader: (1)

Give me the stats on the amount of lubricating properties/percentage that are lost with the fuel dilution... Viscosity and dilution are only parts of the equation, not the complete answer.

SmogSUX

iTrader: (12)

Sadly I can't find the article I'm sure the page "sold out" and isn't a free chart anymore...

http://micapeak.com/info/oiled.html

^This has some interesting info...GTX has a good amount of Zinc. Lubrication!
Has a lot of ash though..not sure if that's bad for us haha

GregW

Cheap *** Halvoline in my stuff

20w50 in my rotary since 2000 - S4 TII. I beat it silly.

20w50 summer 10w30 winter in my volkswagens, since like 1989. With cheap fram filters.

Last vw had 500,000+ miles on it. Current one has 150k+ I abuse my street cars like I have some sort of rage issue. Rev limiter means shift.

Thats why I never buy into the whole expensive oil/filter argument thing. My stuff gets extreamly, extreamly abused and just keeps going. Take them apart and see no wear attributeable to oil brand/weight. So why buy spendy oil?

I change my oil once it gets dark, not on miles.

The blanket statements made in this article are bs. Ive got miles appon miles to prove it.

Now 9k rpm at the track for 30 min at a time, I might consider some sort of synthetic, but only after my dyno PROVED to be inadequate.

Evil Aviator

The dark color of the oil is simply from soot that is suspended in the oil. This is normal, and does not affect the quality of the oil. Therefore, dark color is not an indicator that the oil needs to be changed. If you really want to know if the oil needs to be changed, you will need to send out a sample for an oil analysis. Most people just change the oil according to the manufacturer's recommendation, which takes into account the typical degeneration rate of oil in that particular engine.

GregW

Correct, Thats still when I change it.

Unlike straight weight oil the particles are suspended to help the filter do its job.

Like on an old Model A or a lawn mower you use stright weight unless you have a modern filter.

Ive spent a fair ammount of my life cleaning grime and varnish out of the inside of engines.
If you change it up a bit early- aka when it starts getting dark, the next time you
go in to do something its just a whole lot cleaner. That "soot" and varnish does build up in the nooks and crannys and running oil that is way dirty contributes to it.

The things I change oil on like this I intend to keep till Im dead. Therefore I like to keep them
nice both inside and out.

rksti89

ok so im deeply confused. according to that ferrari article i should be running oil that will have a viscosity level of ten when cold and a level of ten when at optimal running temp. which is about 0w-30. but thats only for daily drivers, i daily drive and do canyon runs so my optimal temp changes. so i should use something more on the lines of 5w-40 or 10w-40 right?

second question is, does any of this go for rotaries too since we also rely on our oil to hold seal and burn? if so wouldn't we want a thick of oil possible to keep compression at cold and optimal running temp?

so with all this and me living in cali with a s4 n/a what oil should i use? 0w-40, 5w-40, 15w-50....?

PercentSevenC

That's why oil temperature and pressure gauges are so important. In my case, my oil temperature doesn't go up by all that much during canyon runs, since they're usually only a couple of minutes at a time and I'm on and off the throttle so much. At that temp my oil pressure is still more than high enough. Better to use the lighter oil if you daily drive the car, since the vast majority of engine wear occurs at cold startup.

Don't worry about the injected oil. Many people here including myself run TCW-3 premix without issue, which is lighter than 0W-30 across the temperature range.

rksti89

see my thing about canyon runs is im doing it for a good two hours or so with brakes in between. when i start, i run a good nineteen mile long road i then do a cool down and stop to check my cars tires, brakes, suspension, and engine. i then do a quick cruise through the mountain back roads to get to the next touge which is shorter but more aggressive with sharp turns and a decent incline degree thats hard on brakes downhill and pushing engine hard on uphill. i run this road about twice each way before taking the freeway home. so should i be more towards the xw-40 range?

PercentSevenC

Again, it's hard to say without knowing your actual oil temp and pressure numbers, but my guess is that you might want to go with a 40-weight oil since you're doing extended runs.

arghx

iTrader: (3)

a lot of the Rx-8's have had premature bearing wear running the factory recommended 5w20, which I suspect was recommended just to improve the score on gas mileage tests to avoid a tax. Mazda also lowered the oil pressure in the 04-08 Rx-8's but brought it back up to prior Rx-7 levels in the 09 models.

I'll stick with my 20w50 Castrol GTX. the loss of fuel economy and horsepower seems minimal.

diabolical1

iTrader: (3)

yeah, i've seen quite a few motors over on the Rx-8 board pulled apart only to find very worn bearings on engines that haven't even made it to 100,000 miles yet. the Rx-8 is a phenomenal car, but in the same breath, i've come to find it a huge disappointment. i still can't see how a rotary-engined car in this day and age doesn't have a functional oil pressure gauge.

slpin

iTrader: (9)

Oil Discussion, synthetic, dino. Just run whatever you feel is best for your motor.

If you are really that **** about it...
Use that Idmatsu stuff that mazda uses. I am pretty sure you can't go wrong with that!

rotarygod

iTrader: (1)

Just to throw some more fuel on the fire, back in the late 60's when Mazda was first getting into racing rotaries, they had a couple of cars entered in the Spa Francorchamp. One car had a ruptered oil cooler about halfway through the race. They couldn't replace it due to a lack of parts but they could bypass it. Imagine racing a rotary with no oil cooler! They did. Their solution was to run a thicker oil. They finshed the race.

I feel oil weight should have to do with certain factors such as climate but also the way the car is driven. If you have a car that does nothing but hold a steady speed down a freeway all day, a thinner oil is probably just fine. If you are going to track it and are going to be hitting redline alot, you probably want a thicker oil. The same principles apply to heat ranges in spark plugs.

I've been playing with different weight oils in my 2nd gen to see if there was an perceptible difference. Of course that's not what matters as engine protection is but I wanted to see if I could get a mileage increase with a thinner oil. I went from the 20W50 that I've always run in my cars all the way down to 5W20. Some people said I'd get oil leaks or the motor would die but it hasn't. It runs fine. I also can't tell a mileage difference. We'll see what happens with various oil weights in the winter during startup. One thing I did notice with the thinner oil is that the smoothness of the engine after an oil change doesn't last as long. At about 1000 miles on the oil, it didn't feel smooth anymore. Maybe it's just mental.

I've since changed the oil out to 5W30 and have found no mileage change. If there was any benefit I'd think I'd see it as that car gets about 100 freeway miles on it a day. Next change will go up again.

Maybe I'm damaging my engine. I don't know. It's mine to risk though and I've got another engine lying around anyways. I bought the car with 120,000 miles on it so any damage may already be done. I won't know until the day I pull the engine. The previous owner ran 10W40 which I know is fine. I'm at 137,000 right now and still running just fine.

The more and more I learn about oils, the more I think weight is less important than oil shear strength. The more and more I learn about rotaries, the more I think we need thicker oils. It's a bit confusing.

rksti89

ah the wise words of rotarygod.... i think i'm just going to go with castrol GTX 10w-40 since its a good range and only 3.99 at the local napa. i saw 0w-40 by mobil 1 which i would love to try but...its synthetic and i'm not sure if their synthetic is ok for rotaries(hell i don't know if any synthetic is still).

blizzaga

iTrader: (2)

I'm nothing wise compared to many of the people around here but I've been running Royal Purple 5w30 for about 2 years now and all is good. I guess to really know I'll need to open it up.




~Shar

RHDturboII

iTrader: (4)

I use non synthetic Castrol GTX 15w50 all year long in the hot climate we have here with no problems.

93vrfd_houston

iTrader: (10)

hey guys...i don't know much on the subject but i recently bought a new rex and while i was at home recently and drove the car oil pressure seemed a lil bit low for my taste. i went to the store to purchase some oil and i was planning on running mobile one 20w50 full synth after reading many posts about this argument on the forum. lil did i know that was harder to find than usual oils and i ended up going with royal purple 20w50 full syth and oil pressure came up to nice levels. it seem'd to run good but like everyone says i guess i'll never know until i open her up.

no_more_rice

No, you need to get the oil analyzed. This is one of the few car forums I'm a member of where UOAs are not routinely posted. If any motor in the world needs the analysis, it's this one.

t-von

iTrader: (8)

Man I'll tell ya the paranoya on these boards is something fierce. LOL! I bought my fd back in jan 03 with 65k. Over a 3 and 1/2 year period I put on 43 thousand miles. I've used quakerstate, penzoil, and castro. I actually prefered the quackerstate because the oil was clearer when it was new and eaiser to tell when it was dirty. All the brands I used were non synthetic. Water steam cleaning every 6k to help control the carbon build-up in the combustion chamber. Hell I even did some motor flushes during that time period. There's no telling what the original two previous owners used. Anyways after overboosting and blowing the orginal engine with 108k, I broke the engine down and found ZERO signs of oil related issues. My rotor bearings are nice and smooth and the e-shaft is perfect. Bearing wise my engine could have easily gone 200k. Apex seal wise is a different story.

I think the real concern should be installing a quality oil filter. I remember reading back a link on here that some guy took apart so many oil filters and did individual testing of their elements and construction. The results on the basic fram filters really shocked me and I never used them again. Oooops that's a lie because I only use the frame during break-in periods on rebuilds. LOL! Hey what can I say, their grip thing is a really nice feature. Anyways I use only a Wix brand for daily use.

Bottom line 99% of you guys are gonna blow your engine well before the bearings can even began to wear out. Change your oil every 3k and make sure you install a quality oil filter (most important thing in my opinion). My results speak for themselves.