Re: what actually BLOWS on an engine from high boost on a stock motor (v.vdubb)
I don't think you're going to break anything at that boost level on a 4cyl so long as it isn't knocking and you're getting enough fuel. I can't really say for sure on a VR6, but if it is anything like the rest of the motors you'll break a ringland or torch the rings before anything really bad happens. If something goes really wrong usually it results in what looks like a bomb went off in the crankcase. I've heard the VR6 rods are good to around 400hp, but I can't vouch for that.
Re: what actually BLOWS on an engine from high boost on a stock motor (vwmikelvw)
If you run it too lean it will blow, and if you run it to rich it will blow,but as for the boost levels I have run a VR6 at 25psi out of a T72 with race gas and no probs. I made 516whp countless times on a STOCK bottom end. Stock rods are VERY strong, they will easily support over 500whp faithfully. Stock pistons are strong but you wont get more then 450whp on pump gas (93octane) without damaging pistons We never blew the stock bottom end with race gas so we do not no the actual limits of stock pistons.
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