RotaryMaybe

Hey guys, i heard royal purple is real good oil to use on our cars. I wanted to try it but what should i get? 10w30? or 50w? i wanta try and stay away from synthetic blends

bureau_c

RP recommended 10W30 to me for my application (FD street use in S. FL).

jds

RotaryMaybe

so 10w30 a synthetic blend?

Street King

10w-30 is just the viscosity level. Rotal Purple is a synthetic oil. Very good IMO.

GoRacer

iTrader: (2)

no a blend is 1/2 dyno & 1/2 synthetic. 10w-30 is multi viscosity. Basicaly it's a 10 weight when cold and and 30 weight when hot. Crude and not perfect explenation. Synce synthetic holds up better the 30 weight can be as strong as dyno 50 weight. I know there's a better and more acurate way to answer but I think the point comes accross.

GoodfellaFD3S

iTrader: (213)

I don't agree with that statement.

I'd recommend going with a 20w50 synthetic.....I have no personal experience with RP but have heard good things. I think Chuck Westbrook and a few other of the Houston crew run RP.

FYI, I emailed Amsoil with my driving habits and a description of my rex and they recommended I use Amsoil 2000 20w50.......

gnobesav

I run Amsoil 20-50, never had an oil-related problem.

DaedelGT

I'm running Royal Purple 20W50 on Rich's advice

One thing I have noticed, switching from Mobil 1 10W30 to the Royal Purple 20W50 is that I no longer have a leak around my oil pain drain plug, or from my turbos. Previously I would get a drop or two from both turbos and the drain plug every time I stopped the car.

rotary-tt

I run 10w-30 Royal Purple ( www.royalpurple.com ). Best to stick with the stock viscosity to keep the oil flow rate up. You need the proper flow rate to get the hot oil out of the motor and to the oil cooler. Many here run 20w-50 so it's up for debate but I feel it's best to keep the stock viscosity if you don't have ported oil passages. Viscosity has nothing to do with the ability of the oil to resist breakdown...

GoodfellaFD3S

iTrader: (213)

I've had a few reputable engine builders tell me that for any kind of spirited/high rpm driving 10w30 is too thin and can cause premature wear to the rotor bearings......

RX-Racer

I use 15w50 in my rotary but use mobile motor oil.
Works nicely.

rotary-tt

Well the car was designed for spirited driving and that what Mazda recommends. Running high viscosity will take longer for oil to reach components on startup when much wear takes place so take your pick. Slower flowing oil will cause it to remain in contact with surfaces longer causing higher temps on these surfaces...

Royal purple has an interesting writup about bearing wear, film strength, etc regarding their oil here http://www.royalpurple.com/indtech/indwhyrp.shtml

EviLPeNeviL

iTrader: (2)

RP 20W50 is the oil of the future!! Great stuff and has increased my miles per tank by nearly 70miles!!

-Dan

Kento

Negative, ghostrider. Part of oil "breakdown" is the progressive thinning of an oil's rated viscosity and film strength due to mechanical shearing actions and extreme heat inside a motor (both of which occur in the 13B-REW engine). That's why dino oils require polymer additives to help them keep (and actually, in many cases, reach) their rated viscosity longer. Nonetheless, this is not to say that we should be running 80W oil in our engines. And the protection advantage afforded by running 20W-50 vs the OEM-recommended 10W-30 oil is debatable (but since my car is modified, I'd rather run the 20W-50). As is the flow rate differences between the two having a meaningful impact on engine performance/protection.

GoodfellaFD3S

iTrader: (213)

There's some good info in that link.....what I'd really like to see is a head to head comparison between Amsoil, Redline, Mobil1, and Royal Purple.

I think another thing to take into consideration when choosing an oil weight is the amount of "blowby," or fuel dilution in the oil. Someone getting a large degree of blowby would be well served to use 20w50.

GoodfellaFD3S

iTrader: (213)

The dancing banana is back! Glad you got unbanned . Dan, you should go post a poll lobbying to bring the crazy yellow bastard to this forum

Kento

Everyone should be careful how much credence they give to information given in the context of an advertisement for a product (however, this is not to say that Royal Purple's products are bunk, as many use them with good results). I find it interesting to note that one portion of that particular RP page shows a bearing surface that supposedly has been "micro-smoothed" out to "reduce friction". They're conveniently leaving out the fact that bearing surfaces never come in contact with each other (other than startup, and even then the improved film strength of many oils helps avoid that as well) due to the pressurized oil film, so the reduced friction claim is highly suspect.

93redFD

whats the advantage for synthetic?

GoodfellaFD3S

iTrader: (213)

Well, that's a loaded question .

Personally, I've found smoother and quicker revving, and a decrease in engine temps of about 5-10 degrees F in all conditions. I've had my motor apart after using only synthetic and found no problems attributable to the oil. Also, turbos love synthetic for the same reasons.....quicker spooling and lower temps.

GP1200R

read the new issue of Sport Rider magazine

nice to have someone as blazingly quick on a bike as Kent is to comment here

hey Kent, do you still stay in touch with Nick Ienatsch?

rotary-tt

I understand you have to take their own advertising in the context of product promotion. Just thought it was interesting. Best scenario would to have a third party test all the oil's claims and represent each manufacturer.

As for the polishing, I believe they are saying the pressurized fluid "oil' is doing the polishing, not that the surfaces are coming into contact. When you wax a car, the fluid (wax) polishes the surface not the cloth

Flame suit on

GP1200R

pressurized oil "polishes" hardened steel?

wake up dude

car polish is basically just a lubricant for the polishing cloth or buffing wheel....wax doesn't polish anything, it's just a surface coating

rotary-tt

And pressurized coal turns into diamonds??

I was using 'wax' loosely - some is just a coating while others do both.

Anyway, that's what Royal Purple says - take it up with them. Ever 'polished' a piece of metal and looked at it under high mag? I have in my eng. Materials class...

Kento

You're ignoring my point: there is no real advantage for smoothing a bearing surface any more than it already is for "less friction", since the surfaces never come in direct contact with each other due to the pressurized oil film. Only in a very specialized application would this be true-- and 99.99% of internal combustion engines don't fall into that category.

rx7tt95

Hey, rocks wear in a river, why can't bearings get polished in oil?

Anyway...I have some useful feedback here. I've been using RP synth for about 3 years now. David Canitz is their head tech and just so happens to race a rotary. I've posted a complete interview I did with him some time back. Do a search for Royal Purple and/or my user name. If we can't find it, I'll repost.

Originally I started by using the Racing 41 Royal Purple. David said it was overkill and to switch to the regular SAE grade oils. I ran 10W-40 up until my last oil change (thanks to a leaky oil pan on my brand new motor). I noticed that my oil pressure was not what it should have been as the motor struggled to see 60psi at full throttle with 10W-40. I broke the new engine in with regular Castrol dino 20W-50 and the first thing I noticed was the oil pressure which was good and high. When I first switched to RP, didn't notice a drop in oil pressure (wasn't really looking). I did notice at about 1200 miles on the RP 10W-40 that the pressure wasn't what it should be. Two thoughts crossed my mind. First, an old pressure sending unit. They're notorious for kicking the bucket early. Second, oil control rings let loose in my new motor. When we fixed the oil pan we noticed that the oil seemed very thin after about 1500 miles of use. Could be fuel dilution. So we swapped out the 10W-40 for 20W-50 Royal Purple SAE grade (or Racing 51) and whammo, pressure went right back up. I live in Southwest Florida where the temps are 95 degrees day in and day out for five months with extreme humidity. I also run a single which is oil fed only, no coolant. I was just very surprised at how thin the oil was after a relatively short period of time. With the oil leak, I had been topping it off daily with fresh oil. So I'm sticking with the 20W-50 for the time being. Just my opinion.