No way you should be using w30 in a track car, w40 minimum otherwise you will just burn it up assuming you are driving it hard
Heard good things about Motul 300v chrono and Amsoil synthetic oils for the track, interesting thread over on NWP4life forum where some of the serious track goers have had oils tested after use to monitor breakdown etc
PERSONALLY though i just use regular castrol 10w40 semi synthetic in my track car and change the oil regularly, will change it after every track day so it's fresh for the next one
More importantly though for a track car you want to look at oil temperatures, you want to keep these as stable as possible, the lubricating properties at 120deg are not going to be as good as at 90 degrees
Oil temperature/pressure gauge is a MUST for any serious track car (on the subject of oil so is a baffled sump), larger radiators, larger capacity sumps and oil coolers etc are very worthwhile, although until you can establish what temperatures you are reaching with your current setup there is no point in spending money on these items
Sorry mate, have to correct you there.
Running 10W40? Is this for your 70s Torana or for the EK9?
Oil burning up doesnt mean its the cause of running thinner oils. Petroleum oils however do burn up much faster physically compared to Fully Synthetic man made oils. Theres a variety of reasons why oils burn up with normal street use and in 1 case I experienced was just due to the brand. Some engines dont go well with certain blends, some do. Its not so much the viscosity, but the blend. This certain oil was Castrol Edge 0w40, our B-series engines dont seem to like this oil.
Every oil company has a Typical Physical Properties chart for each of their oils in which it states many information such as cSt, Noack Volatility, high shear visc, Wear test, etc. This will give you an idea of how the oil fared in this industry standard test. Not all oil companies list every test in their charts, but amsoil and redline does.
The optimum cSt for engine protection is between
7-10
The minimum acceptable cSt for engine protection is
2.5
And for example the viscosity of 100% SYNTHETICS Amsoils(easiest to find)
Amsoil 0w30 oil
@ 40C is
56.56
@ 100C is
10.3
@ 150C(high temp) is
3.2
vs
Amsoil 10w-30
@ 40C is
70.4
@ 100C is
10.9
@ 150C is
3.3
vs
Amsoil 10w40
@ 40C is
102.7
@ 100C is
15.2
@ 150C is
4.2
vs
Amsoil 0w20
@ 40C is
49.1
@ 100C is
9.0
@ 150C is
2.8
90-95% of engine wear occurs during cold startup. Thats right. 90-95% according to oil all the companies. Thats the reason we need to wait for the temps to heat up before we can rev it to the redline, otherwise you'll be inflicting a lot of damage to the engine.
As you can see above;
- Theres a HUGE difference in Viscosity when the oil is at 40C degrees between all those weights.
- However the difference is reduced when oils are at 100C degrees
- And finally, theres shitall difference when the oil is @ 150C degrees
So to conclude this part, the longer it takes for the oil to heat up to the optimum viscosity for maximum protection, the more engine wear is occurring in the engine.
Using thinner oils also reduces internal drag which frees up more HP.
Using INCORRECT oils can result with ENGINE SLUDGE. You will know when you open up your valve cover and see it covered with brown sludge. Also using thicker oils than recommended will increase engine sludge which will result in pour oil flow, pour protection and anything bad you name it.
Thicker oils dont cool very well opposed to thinner oils.
Thicker oils increases oil pressure, more strain to the oil pump.
Thicker oils also leaves a thicker film on the cylinder walls, increasing fuel dilution to the oil which slowly negates the protective properties and additives in oil.
What more to say?
Using lighter synthetic oils in lieu of heavier petroleum based oils offers "more" engine protection while also offering better wear protection too.
Synthetic oils are a whole evolution over petroleum oils nowadays. It is Man-made.
Only very old engines made pre-70-80s need to run thick oils as they are built with 'wide bearing tolerances' which HONDAS are clearly not. These older engine types have no choice but to use thicker oils and they have poor sealing designs etc.
Lots of Race cars these days in Japan, SCCA and even NASCAR run 0w20 and 0w30 fully synthetic oils. Synthetic oils offer superior protection to petroleum oils in every aspect.
Up till now on my EK9 which sees 9300rpm occasionally;
Castrol 0w40 - burnt up and had very bad fuel dilution, oil went black.
Motul 8100 - burnt a bit, oil went black.
Royal Purple 5w30 - didnt burn up, quite good, oil didnt get dirty quickly.
Honda FEO hybrid oil 0w20 - Didnt burn a single drop over 6000kms, engine high response, oil was still pretty clean, wasnt black
Currently Amsoil 0w30 signature oil - This oil is used in SCCA entries and on street cars.
In future, I want to try Motul 300V 0w20 High RPM oil. TRD helped developed this oil for use in their GT race cars. This oil can also be used on street cars.
Never use race only oils in street cars.