03-09-2014, 05:12 PM
Wouldn't be so concerned about boost limit, it's probably about 26psi according to the compressor map,but will go to 28 without too much of an issue, it's whether you're pushing into surge before then which I suspect you are...
This is why you need to be so careful with the stop screw, which since yours was a VK you didn't have, if they close up too much, you will strangle the engine, cause massive EMPs and it'll surge like a fucker, that's what absolutely destroys turbos.
The later GTBs really improve on the surge resistance, also yours being off a fairly large engine, I suspect there will be more of a bias towards air movement efficiently rather than higher pressure ratios - but it's a typical Garrett unit which no one has the compressor map for, so you can't tell.
This is why you need to be so careful with the stop screw, which since yours was a VK you didn't have, if they close up too much, you will strangle the engine, cause massive EMPs and it'll surge like a fucker, that's what absolutely destroys turbos.
The later GTBs really improve on the surge resistance, also yours being off a fairly large engine, I suspect there will be more of a bias towards air movement efficiently rather than higher pressure ratios - but it's a typical Garrett unit which no one has the compressor map for, so you can't tell.