I personally wouldn't go with either of those "kits". The J tuners kit doesn't come with any fuel mods or an intercooler and the downpipe it comes with most likely won't fit an Alero. So you get a bunch of parts you'll need to add to, all for $2500. And Maximum Boost, over on J-body.org, has proven many times he doesn't know what he's talking about when it comes to turbos. Then he wants to sell his own kit....not a good idea, plus he uses very low quality turbos. I spent probably around $2200 piecing my own kit together which includes fuel mods, intercooler and the full turbo-back exhaust. Your best bet is definitly to build your own kit.
But, before you start, do some research, then some more research. Learn how everything works together to make more power and what each individual part in the kit does. Then do some more research. You'll want to know what size turbo you need, what boost pressure to run, how much fuel to add to get a certain air/fuel ratio, etc., etc. There's a lot to know and it can get overwhelming.
I'd be happy to help you out if you're serious about building your own kit. You can PM me whenever or just post on here so anyone else interested can also get help.
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