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A bone-stock [email protected] (dog) version of the engine would make over 400hp on 7psig boost at 5000 rpm :sneaky:, flowing 45.6 lb/min through the turbos and 609 CFM through the carb or throttle body. That's assuming a lot, such as 0.55 BSFC (lb/HP/hr fuel flow), 75% compressor efficiency, and so on.

10 psig would net around 450, and 1 BAR (14.7 psi) would get you 520+ at 800 CFM. Adding 700cc/min (±20%) water injection would bring ±600hp, still at 5000 rpm. Any minor airflow and exhaust improvements would jump those numbers substantially. A stock block will easily take more than that on good fuel and a good tune as boost is lower stress than rpm. Don't get greedy or sloppy. Do have fun.
 

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Gotcha so with the setup I have I need to forge the lower before I add any boost as I'd be well over what the stock lower could handle.
I think you mis-read. I said stock. Bone stock. Only minor changes such as re-gapping the rings and fresh valve springs. Stock crank, rods, pistons, heads, cam, intake—everything. 400 isn't even breathing hard. 700 is easy, but you have to pay attention. You don't get to say "Oops, that was stupid." more than once, no different than a 700hp NA engine.

I would have no issues running stock cast pistons to over 700 on a stock BBF, with those minor mods, and holding rpm to 5000. Reliably. Yes, it's been done and to much higher levels before. Personally, I would go hyper or maybe forged to play 800 or higher, and only to avoid piston land crushing (more boost) or skirt cracking (more rpm). This is the point about letting the boost do the work, as you can have primary assembly stress from boost or rpm. Pick one. Stick to it.

Right now, some are hollering at their screens with something about having to run forged this and that. I agree, if you run crappy fuel, or poor tuning, or other things that add huge stress to the combo. For that, it needs to be armor-plated, and even then is risky. You have to ask yourself; what causes crank failure? Rod failure? Piston failure? Block failure? And they all circle back to some basic elements of rpm, fuel and tuning, the sources of the majority of failures. Keep rpm limited, and invest in good fuel and good tuning. Have fun.
 

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Let's not start A pissing-match on turbo vs super charger, please. Use what you like, and point-out potential benefits of specific types or combinations; but let's not spread generalities of worst-case, as we have enough of that in the web now. Any system can be configured to provide solid solutions, and turbo or supercharger is mostly a preference rather than a requirement. Do your homework, make a plan, and do your thing. :cool:

I don't think you'd even have to regap the rings for only 400HP.
Agreed, but (especially turbo) it usually doesn't stop at the original target power. The urge and capability to just turn that knob a little more gets to most folks. As Hastings and others showed the appropriate wider ring gaps to have low impact on sealing and leak-down, I'd prep the engine for up-to the max it could see with that combo, before dropping it in. The other up-side is that the option to increase the power without increasing rpm is easily available, or decrease it if proper-grade fuel isn't available. Human nature insurance. ;)
I have no available kit as of this moment.
OK, so the perspective of a supercharger salesman is apparent. :LOL: Let me be clear—I love all forms of power adders, including superchargers. I'm here to help however I can, not sell stuff. Some of those statements are way-out there, and either don't apply or are also applicable to SCs. Let's be fair and considerate, and address the OP's questions. My goal is to see user satisfaction, including owner goals, costs, skills, etc. The OP said turbo, so I'll find the combination that does what he wants, likely less costly, more reliable, and easier than other ways. It's his goals that count, not anyone else's.
 
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