If you're going to some kind of power adder in the future, or much more significant normally aspirated power levels, perhaps you need the switch. If that's the case, I'd wait til I made the other modifications.
Go to ProM's website - www.pro-flow.com and click on meter sizing. There's a table there where they show HP levels vs. injector size for normally aspirated as well as boosted cars. According to that data at stock fuel pressure the stock 19's are good for up to 337 HP; 24's up to 426 HP. If I'm looking at your mods and your times correctly, you're well below both HP levels mentioned above, almost a stock set up. I certainly wouldn't put the 30's on or even the 24's. There's no performance gain with your current mods, and the larger ones might affect low speed drivability and fuel mileage adversely. You might have a case of the old "bigger is better" working on you here. I'd resist the temptation unless you've other mods right around the corner. Spend your money on something that un-bottles a flow bottleneck on your engine. And you're nowhere close to a fuel flow bottleneck right now.
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