.
cars

Jump to content


Hello, Allpar Forums member or visitor! If you were an active member (more than two posts) or subscriber, you would not see this ad!

Register for a free account or Sign in (see top right of page for Facebook/Open ID login icons).


Photo
- - - - -

royal purple for flat tappet cams?


This topic has been archived. This means that you cannot reply to this topic.
7 replies to this topic

#1 kzooman83

kzooman83
  • Active Member
  • 330 posts

Posted March 22, 2011 at 09:02 am

Hey all, getting ready to get my Duster out again for the spring, but I want to change the oil first. I have been running Valvoline VR-1 racing oil due to the higher content of zinc and other additives, but I am thinking of switching to royal purple synthetic oil. I have always been told that engines with flat tappet cams require either oils with high levels of zinc or the use of additives with the oil to prevent premature lobe and lifter wear; how does this apply to royal purple (full synthetic)? Is the wear protection of the Royal Purple sufficient or will I have to use additives if I make the switch? Thanks!

#2 AC TC

AC TC
  • Active Member
  • 1,515 posts

Posted March 24, 2011 at 04:15 am

Is this a race car or street car?
Racing oils arent the greatest in streetcars since they dont have
sufficent amounts of additives for soot and sludge control, they also have low TBN numbers
meaning that they cant control acidbuildup inside the engine. They do work good in an race engine that gets frequent teardowns and oilchanges.
To get good tappet protection use an oil with an API index not exiding SM.
Now while royal purple are indeed a good oil that should fullfill your needs i still wouldnt use it.(= price!)
I would use a HDEO instead (big rig "diesel" oil), meeting API CI...CI++ these are cheap and sturdy oils
that meets higher standards than their gas counterparts.(look for rotella, delo, delvac, john deere etc). The HeavyDutyEngineOil (=HDEO)specs
are so stringent that these oils will meet almost any demand an ordinary engine can throw at em. (they are quite popular as motorcykle oil, almost
always used in marine engines also)
Their main disadvantage is availiabilty in lower visc grades, you basically can get a xW-40 but for an summer driven v8
thats no problem. Another disadvantage is package- i always ends up with a 25 liter can but to me thats not a problem.( i use atleast 3 of em a year anyway)
I use these oil in everything except twostrokes....
The only other motoroils i consider are made by Redline, i usually dopes my oil with 5-10% redline to get the natural cleaning and seal sweel properties
of their esterbased oil. This is something you can do instead of getting expensive snake oil and it will gently clean things inside while still being
a really good oil, just make sure you get an oil that is for the proper usage ( motoroil-RL motoroil; ATF+4-RL C+ etc)

Edited by AC TC, March 24, 2011 at 04:51 am.


#3 Cudapete

Cudapete
  • Active Member
  • 3,936 posts

Posted March 26, 2011 at 08:51 pm

Just add STP to regular motor oil. It is ZDDP, aka Zinc.

#4 AC TC

AC TC
  • Active Member
  • 1,515 posts

Posted March 28, 2011 at 03:28 am

Dont add stp to anything, its mostly a bunch of viscosity improvers that gets sheared rather quickly.
There isnt much zinc in any more and the quality of the rest is barely snake oil.
The HDEO´s has all the antiwear you need from scratch.

#5 Cudapete

Cudapete
  • Active Member
  • 3,936 posts

Posted March 28, 2011 at 05:29 pm

SM oils, even the Diesel oils, do not have enough Zinc. STP is an easy way to add it. I use Shell Rotella and STP in my Cuda. Works just fine.

#6 AC TC

AC TC
  • Active Member
  • 1,515 posts

Posted March 31, 2011 at 07:27 am

Dont use SM oil get CI- CI++ instead.

#7 kzooman83

kzooman83
  • Active Member
  • 330 posts

Posted March 31, 2011 at 08:56 am

Probably should have mentioned what engine; 400 big block, .030" over, keith black hypereutectics, cam is a Comp XE 275 HL; 231/237 duration @ .050 with .525/.525 lift, hydraulic flat tappet.

Not a race engine, just high performance street.

#8 AC TC

AC TC
  • Active Member
  • 1,515 posts

Posted April 1, 2011 at 03:32 am

That thing should pull nicely...
But its not a race engine and its street driven- id use any HDEO in xW-40 flavour and no snake oil.
Side note: Dont get overly worried about zddp/ zinc since there are other additives that have it´s function.
But avoid the newest SL,SM oils since they do have lower contants of these additives and thats for resons like,
emissions and the fact that newer engines doesent need em as much. (read lower tappet loads, roller cams)


.
Allpar

Home · Cars · Engines · Repairs · People
Tool and Car Reviews · News

Please read the terms of use and privacy policy. We are not affiliated with Chrysler Group, makers of cars, minivans, trucks, and Mopar (TM) parts. We make no guarantees regarding validity or applicability of information, opinions, or advice. Posts may be edited and used in other parts of allpar.com and affiliated Mopar (Dodge, Chrysler, etc) car related sites. We have the right to remove or modify any message, and to ban or suspend any user without notice. Logos and site-specific information copyright © 2001-2013 Allpar LLC; Chrysler PR materials remain property of Chrysler Group.