what tune for CS turbo?

[mituc]

Originally Posted by TheSixthSpeed I want to know when you started tuning the car to know if you got the older batch of turbo's and if the problem should technically be solved in the design by now. I'm still on the K04 and plan on pushing it as much as possible with meth and hope it lasts a year till I get the S3 or I could get the CS now instead.

That is something I don't know and I can't verify.

As a side note (wall of text following) if you're on stock block the S3 may be a bit more appropriate even if you use meth. The reason is that the factory pistons are not able to handle heat very well and with a GT30frame turbo (and the CS turbo is one of them) you will get maximum power upper in the power band, around 6200-6500rpm. So at 6700 which is the factory rev limit the turbo will still be able to push quite a lot of air efficiently.
Even if you resist the temptation to up the rev limit which is a no-go in my opinion on a stock internals engine, making the peak power upper in the rev range (probably 500-1000rpm later than an S3 depending on the tune and gas you're using) the pistons will take a lot of heat and you'll run into cracked ringlands issues. That will happen even if you use meth, because with the extra cooling from meth and the additional fuel you will definitely up the boost and timing which eventually will result in abut the same head endured by the pistons and cylinders.

So if you're on stock block get the S3 and use that extra 300-500rpm in the 3200-3700 range which with a GT30 frame turbo (CS, BNR S4, GT/GTX3071) is kind of lost, because that will usually make up for the 300-500rpm you loose up top with the S3 over the GT30 turbos. Also, on a stock block the GT30 turbos have more potential than the stock block can use safely, and in the 4000-6000 rev range the S3 and a GT30 turbo will perform similarly on a stock block (because of the limits of a stock block, not because of the turbo potential which is slightly higher even in that range with a GT30).
Makes sense?

P.S.: the factory pistons oil rings are absolutely and totally fucked and drowned in soot deposits after 30-40k miles of use, using some kind of oil flush or sea foam before you upgrade the turbo (or even start tuning) is a tremendously good idea which will delay the ringlands from cracking for quite a while. The clogged oil rings means less lubrication and cooling from the oil and remember, heat is the no #1 enemy of a factory piston.