So its time for a oil change andI was thinking about going back with royal purple. Right now I have plain jane havoline 10W-40 and I was wondering ifI would see any kind of improvement with the royal purple 10W-40 (performance, longevity, etc.). Also is thecost worth the improvements?

 

Isn't RP good for 10k miles? As opposed to regular oils at 3k? For price, it seems like a no brainer since it isnt over 3x more expensive...

Course, I would do less than 10k mile intervals..

 

On a street engine?? No, sadly the benefits of reduced friction, wont recoup the expenditure. Especially on an older loose tollerance engine that allows more pollutiants into the oil, vs a tight tollerance more modern engine. Its the acids & other pollutiants that break down an oils life span in a street engine. Royal Purple Oil is more for racing engines where ever little bit is needed. A synthetic blend oilwill be more suitable, for a street engine, if Ya just gotta.

 

I was wondering how it would do with a street engine. So I'm assuming that Lucas or AMsoil or any other synthetic wouldn't really be worth it on a daily driver?

 

In my opinion, not really. There are a lot of variables.
If you have a new fresh engine built to tight tollerances(modern CNC type machining, on production engines has this) and you plan to maximize the extended 8-10k mile fluid change programs, Synthetics are great.
On an engine built 25 years ago, & your fluid change schedual is 3k miles, why throw away money??
Some folks choose to do so, as is their right. I would feel wasteful,doing thatmyself.

 

The only advantage to going with a synthetic like that would be the little (very little) power increase you would get with the reduced friction.

 

At Schucks Royal Purple is a little over $5 a quart. Good deal. A good synthetic oil is $4-$6. Classic is right about synthetic oils but if you can get a good deal than why not?
[align=left] [/align]

 

Synthetics offer a lot of benefits over conventional oils. The number one is the reduced wear and tear on the internals. You'll also gain power and efficiency, but as mentioned, you're not likely to notice without a lot of instrumentation. I've seen people gain 1-2mpg with a synthetic oil change, but that isn't necessarily a norm (that was on an '91 Explorer with 160k miles on it).

When used per the oil manufacturer's direction, synthetic oils are much less expensive than conventionals. Amsoil with its 25k/1yr change interval is probably the least expensive, though still very high quality.

 

I have a 69 coupe/390 big block which burns about a quart of oil every two weeks. Who needs an oil change.

 

[align=left][sm=icon_rofl.gif]I've been there