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Message: [QUOTE="KCTurbos, post: 1041893, member: 13852"] I have often thought about trying out a higher stall to see what happens. I don't know anyone running a higher stall with a big vgt... but I do know a few guys that had bad transmissions that were shifting/stalling weird and made the turbo spool like crap. Once they got a new tranny it was like a whole new truck. Logically I could argue both ways about how much it could help. But this is how i see it. A higher stall converter helps you to get higher up the in rpms sooner so that the turbo can operate more efficiently sooner. Big turbos don't like low rpms. You can look at the dyno and compressor maps that I put up and see that the big turbos make less power down low... so the sooner you can get them into their peak operating range, the quicker they will spool, run more efficiently, and the better your truck will run. A higher stall converter would definitely help guys off the line. It will help the turbo to hit that sweet spot much sooner. But most big VGTs don't usually have off the line issues with power. Most guys have a hard time keeping the tires from spinning if you roll into the throttle and floor it. Where big vgts struggle is when guys are cruising around at 1700-2000 rpms. You can see from the dyno graph that under 2500rpms the smaller turbo is actually running more efficiently and making more power. The opposite is also true, the bigger turbo will be running less efficiently and making less power (even at light throttle). The vanes can help get the turbo spool up sooner... but it still won't operate as efficient as as smaller turbo under 2500rpms... no matter what you do. Those same vanes that help the turbo spool sooner become a slight restriction and can cause a loss in efficiency which usually leads to slightly higher egts (as opposed to a non-vgt which is more free flowing). [/QUOTE]