Royal Purple Motor oil
Royal Purple Motor oil
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
Joined: Oct 2001
Posts: 4,772
Likes: 2
From: My 350Z Roadster kicks my RX7's butt
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.
Joined: Mar 2001
Posts: 30,804
Likes: 646
From: FL-->NJ/NYC again!
Originally posted by GoRacer
Synce synthetic holds up better the 30 weight can be as strong as dyno 50 weight.
Synce synthetic holds up better the 30 weight can be as strong as dyno 50 weight.
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.......
Trending Topics
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.

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.
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...
Joined: Mar 2001
Posts: 30,804
Likes: 646
From: FL-->NJ/NYC again!
Originally posted by 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...
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...
Originally posted by GoodfellaFD3S
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......
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......
Royal purple has an interesting writup about bearing wear, film strength, etc regarding their oil here http://www.royalpurple.com/indtech/indwhyrp.shtml
Last edited by rotary-tt; Jul 21, 2003 at 11:32 AM.
Originally posted by rotary-tt
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...
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...
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.
Joined: Mar 2001
Posts: 30,804
Likes: 646
From: FL-->NJ/NYC again!
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.
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.
Joined: Mar 2001
Posts: 30,804
Likes: 646
From: FL-->NJ/NYC again!
Originally posted by EviLPeNeviL
RP 20W50 is the oil of the future!! Great stuff and has increased my miles per tank by nearly 70miles!!
-Dan
RP 20W50 is the oil of the future!! Great stuff and has increased my miles per tank by nearly 70miles!!
-Dan
. Dan, you should go post a poll lobbying to bring the crazy yellow bastard to this forum
Originally posted by rotary-tt
.Royal purple has an interesting writup about bearing wear, film strength, etc regarding their oil here http://www.royalpurple.com/indtech/indwhyrp.shtml
.Royal purple has an interesting writup about bearing wear, film strength, etc regarding their oil here http://www.royalpurple.com/indtech/indwhyrp.shtml
Joined: Mar 2001
Posts: 30,804
Likes: 646
From: FL-->NJ/NYC again!
Originally posted by 93redFD
whats the advantage for synthetic?
whats the advantage for synthetic?
.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.
Originally posted by 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.
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.
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
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
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
Last edited by GP1200R; Jul 21, 2003 at 01:54 PM.
Originally posted by 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
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
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...
Originally posted by rotary-tt
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
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
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.
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.





