which oil for track days

[HUX500]

I am going to flush out the old oil before my first track day (bedford 20/2) and then change it (and filter) after every second track day.

What would you put in a E30 325i with 125,000miles? No engine mods yet.

Is synthetic a waste on this old girl? What grade e.g 10W/40 etc?

The bloke in Halfords suggested an oil for engines with high mileage..

thanks

[james28]

best to put what ever the recommended in it says
no point spending loads on racing 10 60
just make sure its changed regular

[Burrow01]

HUX500 said:

I am going to flush out the old oil before my first track day (bedford 20/2) and then change it (and filter) after every second track day.

What would you put in a E30 325i with 125,000miles? No engine mods yet.

Is synthetic a waste on this old girl? What grade e.g 10W/40 etc?

The bloke in Halfords suggested an oil for engines with high mileage..

thanks

Would suggest if you are doing track days that a synthetic oil would be worthwhile. They are specifically engineered to retain stability at high temperatures, and to be resistant to high shear forces experienced on the track - you can save money by extending the change intervals and keep the same protection levels as with a cheaper oil

Pete

[chris7676]

The problem I noticed with thinner synthetic (0-40 against 10-40) is that it dissapears much faster, at least in my 2 cars (1988 & 1999).

[iguana]

10/40 semi synth & change it regularly, utter waste of money fully synth on that old engine.

[teabagger]

if it was me i would go for 10/40 - the stuff they sell in euro car parts for £15. change it every two trackdays.

[Burrow01]

iguana said:

10/40 semi synth & change it regularly, utter waste of money fully synth on that old engine.

Because?

Track days beat the hell out of oil, so why not use a fully synthetic? How much faster do brake pads and tyres wear on a track day than in normal use? You think the oil has an easier time?
Age of the engine is irrelevent, if you are revving it to 6000 all day, you need the oil to stay in shape, and thats what fully synths give you.

Pete

[minerva]

Agreed. If driving the car for what it was intended, ie on the road, then put the recommended oil in. If thrashing it around a track then put improved specification oil in. That means synthetic stuff.

[HUX500]

cheers guys, the old girl will get fully synthetic. Lucky thing!

[iguana]

Burrow01 said:

iguana said:

10/40 semi synth & change it regularly, utter waste of money fully synth on that old engine.

Because?

Track days beat the hell out of oil, so why not use a fully synthetic? How much faster do brake pads and tyres wear on a track day than in normal use? You think the oil has an easier time?
Age of the engine is irrelevent, if you are revving it to 6000 all day, you need the oil to stay in shape, and thats what fully synths give you.

Pete

Because old engines that have never run synth & have been fairly oil tight tend to leak it from every seal when thin synth is suddenly used.

Also it tends to be thinner & seaps past valve stem seals & valve guides & rings & a previously smoke free engine can smoke like Ivor the engine. the tolerances when new wehernt build for modern synths, let alone when they are old & baggy.

Its an old low revving non turbo engine, with an oil cooler it won't get that hot, I used to see 100deg max on mine, if it was turbo I'd say syth of course.

I change it on average every 2-3 trackdays- circa 300-400miles odd, works for me engines stipped after 30 odd track days have shown naff all wear, if synth works for you fine, but I've run many track cars on more basic oil for many yrs & have worked in enviroments where they did the same.

[SpeedyDave]

iguana said:

Because old engines that have never run synth & have been fairly oil tight tend to leak it from every seal when thin synth is suddenly used.

Also it tends to be thinner & seaps past...

Not really convinced about this, why are synth's 'thinner'?
Seems like the old myths born out of;

- synths usually don't need a heap of viscosity modifiers to stop them thinning when hot, and they flow better when cold (both good things) so they seem 'thinner' out of the bottle. Nothing do do with getting past seals though but...

- PAO / Esters tend to shrink / swell seals, a bad (early?) synth that wasn't a suitable mix of the two might cause seals to contract and leak, I guess the mud stuck. A modern synth should be fine, unless it was a really crap one I guess.

iguana said:

Its an old low revving non turbo engine, with an oil cooler it won't get that hot, I used to see 100deg max on mine, if it was turbo I'd say syth of
course.

I change it on average every 2-3 trackdays- circa 300-400miles odd...

Yeah, if you keep the temps sensible there is much less need to get exotic with the oil. With some engines (old / worn) the main threat to the oil will be contamination in which case you'd be better off using a less expensive oil and changing more often.

[HUX500]

I think i will meet eveyone half way and go for a semi synth then.

cheers

[Burrow01]

SpeedyDave said:

iguana said:

Because old engines that have never run synth & have been fairly oil tight tend to leak it from every seal when thin synth is suddenly used.

Also it tends to be thinner & seaps past...

Not really convinced about this, why are synth's 'thinner'?
Seems like the old myths born out of;

iguana said:

Its an old low revving non turbo engine, with an oil cooler it won't get that hot, I used to see 100deg max on mine, if it was turbo I'd say syth of
course.

I change it on average every 2-3 trackdays- circa 300-400miles odd...

Yeah, if you keep the temps sensible there is much less need to get exotic with the oil. With some engines (old / worn) the main threat to the oil will be contamination in which case you'd be better off using a less expensive oil and changing more often.

Synthectic oil cannot be "Thinner" - a 10/40 oil is a 10/40 oil - thats its measured grade - in fact a synthetic will stay in grade, and not break down to a lower viscocity longer than a non synthetic.
People tend to use a lower viscocity synthetic than they have non synthetics, as they are often marketed as "better" but if you are using a 10/40 now then a 10/40 synthetic should not leak any more than a synthetic - sometimes the detergents are better in a more expensive oil, and can flush out crap thats been holding gaskets etc together - that might be one source of the rumour. I have an engine with 179,000 miles on the bottom end and no leaks when switched to synthetic oil.
Temperature is not the only thing that breaks oil down - the mechanical forces when camshaft lobes etc are spinning at high speeds can physically "chop" the polymers that keep the oil at the higher viscocity into pieces and they lose their effectiveness, making the oil unable to retain the 40 rating at normal temps
Beware of oil marketed as "semi synthetic" - there is no regulation of the content of synthectic oil that it needs to contain to be called Semi....

Pete