Did you twin turbos come with built in wastegates? Reason I ask is that alot of those ebay kits come with internal wastegates. Your stock internals will outlive the block. I have seen cars split the block with as little as 350rwhp and have seen others live at 580rwhp. As a general rule keep it to about 480 with a good tune and it should live for a while. I would suggest that you have the heads checked for straightness, run studs and a MLS gasket (fel pro, cometic). You will need a 255 pump, 42 injectors and a boost referenced regulator. As for the computer, a tune is good but not necessary. You can run your timing locked at 19 or 20* depending on the type of fuel you run. Start with 40 psi fuel pressure with the vacuum spout off and go from there. You could also look into the XPI timing lock. It runs normal timing until a desired boost level then locks it from there on out. I wouldn't go with a tune at first because you are going to end up wanting more boost. If you up the boost your tune will need to be redone=$$$.Go to the turboforums.com ever question you can think of has already been answered 100 times.
Here is a video of my car with a single turbo at 9psi first day out with no tune and 7 cylinders (fouled plug). 100% stock motor. MPH was 114.7, 2.01 60'.
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