I was interested in what Tooley had to say on type of oil - synthetic versus non-synthetic. My na registers a vast range of oil pressure between hot and cold and I run it on synthetic and was wondering if the oil was too thin. Any comments or recommendations?

 

Jack,

 

Go onto twinturbo.net and use the search feature for "mobil 1" or "synthetic". The oil pressure will drop a lot when hot, there are many aguments about the weight of the oil. I was considering using a thicker Redline oil, but for now I'm sticking with Mobil 1 to look after my turbos.

 

I would NEVER reccomend non-synthetic in a TT 300.

 

Synthetic oils, like traditional oils, come in different viscosity ratings and it is just as important to get the right one. I know Mobil 1 do a really light oil and a slightly heavier one.

 

Like Jez, I've always stuck with synthetic but as I said on the earlier thread, how many of us can put hand on heart and say we really know ! What I CAN say for definite is that I noticed that the oil pressure was higher after hard driving when I changed from semi-synthetic to synthetic.

 

There also appears to be little argument that a fully synthetic oil is more effective during the first few seconds of starting the engine.

 

Dave

 

It's supposed to dramatically help stop the turbos from coking up and therefore extend the life of them.

 

Like your say Hairsy, I only know this from what so many people keep saying. I take my advice from a few 300 mechanics and the majority of twinturbo.net feedback. The web sites for the oil manufactures probably make a good read also, but I can't be bothered.

 

synthetic oil should NEVER cook, even under the heat generated by the turbos.

 

so when you stop the car, if you are using synth oil, you no longer have that worry, however....

 

this does not mean that you can get rid of your turbo timer if you use synthetic oil !!

Oil cooking is only one of the problems, the other is that you need to let the turbos SLOW down !

 

When you stop the car, your turbos could still be spinning at over 40,000rpm, even as much as 70,000.

 

The oil has to lubricate those bearings while the turbo is spinning.

 

That's the main reason turbo timers have variable time delays depending on how much boost, and how recent, the turbos have generated.