Just thought I'd bring up this discussion again. - Read an article in the Mini Magic #4 on a supposed comparison between Mineral and synthetic oil.
(Penrite HPR30 and Royal Purple Synthetic) The article claims a 9% HP increase with the synthetic and better (more stable) oil pressure. I say supposed as although they used the same car and a new filter they only did one run with each oil on the dyno.

Does anyone know of more prolonged and thorough investigations into the use of synthetic in the A series? or we just going on emotions and heresay?

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Don't use synthetics in A series engines.

I made the point of asking a Caltex technical guy exactly why, and had it all explained to me at length....I have since forgotten though...I remember the "dont use sythetics" bit though.

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No more Minis!......For now.

That's interesting.. I remember reading something by Keith Calver involving synthetic oil, and he didn't object.. I'll see if I can dig up the link.

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Simon

The adventures of an owner builder in the Tallarook Ranges

I Totally agree Don't use synthetic oils in an A series engine.

I made the mistake of doing that a few years back and it was a mess. The car didn't run at all happy and more to the point it pissed out of every oil seal in the car and was running out of the motor as fast as I could poor it in. Also the seals were all new as the engine had just done a rebuild and this was it's third oil change. For some reason it just ran past all the gaskets like they weren't there.

I changed it back to a good old mineral based one and the car was allot happier and the oil only dribbled out like normal.

Maybe someone has found a good synthetic that's okay but after the above experience I'm going to stick with good old mineral gear.

Mal.

Found it. The full article at Mini Spares is here.. a very interesting read. This is also where I read about high-detergent oils being bad for Mini gearboxes.

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Simon

The adventures of an owner builder in the Tallarook Ranges

if you could find a fully synthetic designed for classic cars that would be good.

There are a few historic racers in the US using synthetic, but its not like the "watered" down stuff available at supercrap, costs them over $140+ to put new oil in the engine.. From memory i think it was redline branded stuff, that royal purple is very nice stuff too i've heard..

If you want me to find out more details let me know

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i allways love oil discussions
first of all i am using syntetic oils since my first mini without any problems. syntetics are better than minerals, they can cope with more pressure and heat.
sure, the a-series is happy with a good mineral oil but it won't die if you use syntetic. and the gearbox has no problems with syntetic.
with syntetics you may find the engine runns cooler and stays cleaner.
but you have to compare the right oils, you can not take a mineral 20W50 and compare it with a 5W30 syntetic. the syntetic will probably still outperform the mineral in pressure and heat but it can't give the right viscosity when hot.
and by looking at the viscosity, it says nothing about the qualitiy of the oil just how it flows at given temps.

if you engine starts to leak with syntetic its not because of it attacks the gaskets, it just removed some of the dirt that tried to seal. or you used some "thinner" oil that went more easily through the existing non-sealing gaskets. with new gaskets there shouldn't be any oil dripping, no matter if mineral or syntetic

to find a syntetic thats good with classic cars you just have to look at the specs (but you have to ask the manufacturer as they are not printed to the bottle) and to know what your engine needs

after all, the best advise is: if you are happy with the oil you are using, stick with it

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Rover 214 atm ....

I did an oil change on the weekend and put Penrite HPR30 in, unaware that it is now a synthetic oil.

Gotta say, she feels a hell of alot smoother now, both in gear changes and in initial accelleration.

I'm kinda torn on switching to an all mineral oil on my next change, considering the car is running so well. But i guess if all mineral is better for the engine in the long run, it's the right thing to do.

!! You sure about that?

I used HPR40 once or twice, it's a semi-synth and I have to say i liked it..

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

I used HPR50 (40W/70) once in my son's Clubby (oil burner) one winter in Sydney.
Poured it in, started it, couldn't get gears.... It was so thick it stuck the primary gear to the crank. And it was Fri night, he HAD to go out...
So I drained 1L or so out and topped it up with diesel fuel. We ran it for a week or so, was great flushing oil. Cleaned the crud out good.
Not that I recommend this approach..

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

On my freshly built engine I ran 15W40 Valvoline Super Diesel and it ran much better than 25W50 Formula R. I have read the article by KC mentioned above and I think the HP gain could be to do with how much thinner Synthetic is? who knows

More fuel to the fire: Not all synthetics are the same, there are ester based synthetics which are "real" synthetics and there are cheaper oils made from refined mineral base stocks which are also labelled as "Synthetic". (Ever noticed why Mobil 1 is twice the price of any other "synthetic" on the market?) Who know where the "don't use synthetic" debate comes from? could it be that they were using yesteryear's cheap synthetics? Who knows if the more expensive synthetics like Royal Purple actually works or not? Yes HP gain but what about 100,000miles?

I am not pro or anti synthetic btw I am just relaying information.

I have considered for some time now that I will one day run a freshly built1098 clubman with fully synthetic "top grade" oil and see what happens to the valve train and gearbox under a microscope. This should end all arguments pretty quickly

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Lillee - 1969 Morris Mini K

I would be more worried about camshaft and lifter wear than the gearbox..
Castrol GP50/Formula R/Edge 25W/50 was designed to eliminate cam and lifter problems in Holden V8 race motors.
On a V8, the cam is hanging in the breeze, just like an A series. All ours gets is splash lube from the crank and rods.
All the little multivalve Jap etc whizzbang twincammers have the cams etc sitting in an oil bath, thin oilz works fine for those.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

syntetic vs. mineral is not thin vs. thick, you can buy 20W50 syntetic

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Rover 214 atm ....

we use motul v3000 in the race cars and no problems and its a really good oil.
most of the commercially available oils are for modern cars and dont fair to well in an A series with box on bottom but the motul or Q8 F1 oils are brillaint and will give more horses to over mineral oils.

purly cos of ineral oils lacking a few ingredients now days has made me search for better quality oils that you can buy off the shelf.

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www.minicranks.com add me to your watch list and come back again soon, under construction.