Well, here, I'll comment.
Yeah, I guess TST and Smarty both effect duration and timing. Most find that you're better off to use the timing offered by Smarty, and not by the TST (that is if you have the TST box that will allow you to adjust timing. ) If the TST you have won't let you adjust timing manually, you should probably run an even-numbered Catcher on the Smarty.
As I understand it in simplified terms, TST effects the duration by a specific percentage at a setting. Thus, the duration of the injection event is increased by this same percentage across the entire speed/load range.
Smarty is different. It changes the fueling and timing maps in the ECU. Thus, the timing and fueling are not increased by a fixed percentage, but each point on the map can be altered individually. This could allow for much smoother transitioning than a plug-in type box provides.
Smarty also alter (or takes away) torque management, which derates power on the low end to help protect your drivetrain. There is a huge difference in driveability between stock torque management and wild.
I would say an upgraded turbo would be a better place to start before adding the Smarty. I know with my TST and stock turbo, I could peg high EGT's in no time. Adding Smarty is only going to make this worse.
After you add a larger turbo, then purchase Smarty... You're not going to be able to use this combo to its potential with the stock CP3. I can easily drain the rail on even moderately low settings with my TST/Smarty/TS MP-8 stack.
I don't think extending duration has that big of effect on injector life. Some say multiple injection events place more wear on an injector over just going with one main. Additionally, raising rail pressure will lend toward increased injector tip wear.
Hope this helps somewhat. --Eric
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