best oil for crossflow

[eric]

Hi

 

Who can tell me what is the best oil for my 110 HP Sprint Caterham, and when do you advise me to change it.

The 7 is running with 2 40 Webers, a wet sump and no oil radiator.

 

Many thanks

 

 

[Roger King]

Personally, I would recommend Mobil 1 Racing (the 15w/50 grade). This doesn't mean that other oils are not good, just that we have always had excellent results with the Mobil product.

 

If the engine has done lots of miles, it probably isn't worth switching to an expensive synthetic like this. In this case a good quality standard type oil would be better, perhaps Castrol GTX.

[millsn]

I got onwell with the thicker version of magnatec

 

Nigel Mills - 2.0 Zetec carbs

[domster]

As you have a relatively low state of tune, I would say the Mobil 1 15w50 competition is probably overdoing it. It is my favourite synthetic of all time, and I use it in my Lotus Carlton, but believe me, at 35 quid for four litres or whatever Halfords charge, it ain't cheap. Roger's the engine god, though.

 

Personally, I would recommend Halfords own brand semi-synthetic. It will suit the older x-flow better, and I used it in my 130/140bhp x-flows without problem. It is about 12 quid for 5 litres or something.

 

I'd use the Halfords own brand for half the price, and do oil changes every 3k miles. In my experience, the x-flows always ran quite 'dirty'.

 

 

[Bafty Crastard]

Caterham recommend a mineral or semi sythetic oil only !

 

I suggest you try Comma XT2000 15w-40 semi sythetic @ £11 for 5 litres and save your self a hole lotta money smile.gif

 

Edited by - Bafty Crastard on 10 Oct 2001 12:31:16

[John Alston]

I have used Mobile oils for a number of years initialy Mobile One in a very fragile Turbo Esprit and now Mobile Competition 15/50 in my Cross Flow. Mobile synthetic is lovely stuff and does an excellant protection job on your engine.

As for concerns over its high cost, as the majority of sevens do low annual mileage, there is often only one oil/filter change required per year. Small price for peace of mind I say.

[Bafty Crastard]

When I spoke to Caterham a number years ago about post running-in use of a crossflow engine they specificaly stated, DO NOT to use a fully sythetic motor oil.

 

I guess it could be interesting if you had a warranty claim and was found to be using a non approved oil ! but perhaps that time has long gone

 

Edited by - Bafty Crastard on 2 Apr 2002 08:08:02

[Graham Sewell]

I remember talking to a once-revered engine builder by the name of Blydenstein (I hope that is spelt right) and his thoughts ran along the lines of:

 

If you cchange to oil every 3000 miles it doesn't matter what oil you use. The main advantage of fully synthetic is that it can easily do 15,000 miles before a change.

 

Therefore, I would question the use of Mobil 1 in any Seven that is serviced regularly...

 

Nomex underwear being donned...

 

Cheers,

 

Graham

 

[Simos]

 

IMHO I don't see why a modern engine (even if an old design) shouldn't use a synthetic oil, esp if it is relatively thick like 15/50.

 

One of the advantages of synthetic oils for modern engines has been to get the cold rating down to 0 (0w/40) which gives better protection to an engine when starting from cold - and doing the majority of it's running life below running temp )

 

You carefully warm your (any) engine then go for a blat in search of some bikers to scare the crup out of

You regularly blast it round a circuit on trackdays

The engine is out over winter being upgraded

You have 3 complete sets of wheels and tyres of increasing size and stickiness in your garage

You should have Mobil 15/50 in it for high film strength at high temperatures and insane revs.

 

You don't do track days 'cos it's your pride and joy (the wife'll never let you get another if you trash it)

You drive in town and go to the shops in it (any excuse)

You drive summer and winter

You go for a blat but don't actively chase R1's

You have 14" 021's for an ideal compromise between performance, ride height, longevity and price.

You have 0/40 in it to give you more protection for the many/cold starts you do - almost any decent oil will do.

 

But seriously

 

I doubt there's much difference between oils of a particular grade and type eg. Comma and Mobil, synth, 0/40. Not sure Comma do a 0/40 but you get the idea.

 

There's a school of thought says oil changes are dependant on starts and run time below operating temperature (Station car 8 miles/day - change twice a year every 900 miles, RAC van run in shifts - change twice a year every 30,000 miles)

 

Cheers, Simon.

[R2D2]

I run a Twin Cam on Castrol Product 351, which is a straight 40 grade. It is a development of CRI 40 which was used by Ford in the Works Escorts for quite a few years. I have used it in various Twin cams, BDAs and Imp engines and never had a problem.

I suppose some of the modern oils are possible better but I have long experience with this oil in rally cars and find it difficult to abandon. It is quite detergent and I do change it every 3000miles.

 

I don't really worry about using multigrades in my Seven and maybe this is a

mistake (?) but I do tend to warm it up carefully and drive it reasonably hard so I don't think a multigrade would be too important. (?)

[Super_Rich_Bernie]

Last week the Sainsbury Supacentre at Colliers Wood had mis-priced Castrol RS 10w60 synthetic at £1.99 for a litre bottle.

 

The 4 litre can was still £26.

 

There were still plenty of bottles left after I had stocked up.

 

Sainsbury's may have cottoned on by now though.

 

regards

 

Jonathan

[Paul Turner]

Over the past 13 years the criteria I have applied to choosing oil for my x-flow have been that it is a good quality semi or fully synthetic available locally for a reasonable price. The three I have used have been Duckhams QXR, Valvoline 15 40 and most recently Millers 10 40. None of these have given any problems and I have always changed at a max. interval of 2500 miles or every year. Many years ago I was advised to use Valvoline Racing 20 50 and I immediately got a bizarre problem that I have never heard of anyone else suffering from. The oil pressure was normally about 70 psi when cold falling to about 60 psi when hot at normal cruising speed. After filling with 20 50 it started out at about 30 psi when cold rising to 80 psi as it warmed up and then falling to 60 psi when hot, I immediately changed the oil and filter reverting to the previous oil and the problem had gone. The engine was dry sumped and the explanation my engine builder gave was that the oil was possibly too thick when cold for the pump to cope with having to pump it to a remote filter and back to the engine. I think its fair to say all "quality" modern oils are better than what we were purchasing 20 years ago.

Now to hijack this thread, I have just installed a Zetec and Ford recommend 5 30, is there any brand preference considering that although there has been much said about what to use in a VX to avoid noisy tappets nothing has ever (as far as I can remember) been mentioned on this topic and Zetecs.

[John Whyman]

I,m with bafty on this one. Comma semi-synthetic. Good product and sensibly priced. I change oil and filter every 3000 miles. No problems at all.(1700 x/f supersprint)

 

Happy Motoring. thumbsup.gif C7 WJW.