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Message: [QUOTE="me2, post: 331392, member: 3825"] I'm getting questions about the turbo stuff and how I arrived at my HP estimation. I don't have time to go into detail right now, but here is a link to a calculator set up with my numbers in it. [URL="http://www.not2fast.com/turbo/glossary/turbo_calc.shtml?FeetASL=0&Tamb=21&Bore=106.9&Stroke=124&nCyl=6&RPM=2800&VE=100&Boost=40&Ec=75&Eic=80&PdropIC=0.5&TambIC=21&wiPercentMethanol=50&wiRate=100&wiTemp=21&SFC=0.39&AFR=20&maxInjectorDutyCycle=85"]My data.[/URL] If you are interested, you can play around with the various factors and see what results. I did not use this calculator to get my numbers. I used a spreadsheet. The two give very similar results, which I take as a positive sign. Obviously, I made a few assumptions to get there, namely intercooler efficiency, air fuel ratio and BSFC. These assumptions may or may not be accurate. Rather than debate them, I want to get my truck running and measure what it does in the real world. The calculator is set up for a single turbo. You can simulate twin (compound) turbos by using the overall boost pressure and the combined efficiency for the pair. The biggest fear I have is that the turbos are going to overload the intercooler as far as cooling the charge goes. Note that at 40 PSI of boost the temperature out of the turbo is estimated to be 199C, which is 390F. And that is with a turbo at 75% efficiency. Should that be the case, I'll probably add an interstage intercooler or an air to water cooler. One more thing. All these simulations assume that the engine has enough air flow and heat in the exhaust stream to spin the turbines to turn the compressors to build the boost that is necessary. Usually the turbo manufacturers size the turbines relative to the compressors, so if you size the compressor correctly for the engine, generally the turbine isn't too far out. On a dyno run there is usually such an excess of fuel and heat that spooling up an oversized turbo isn't a problem. My engine is going to be entirely different in that regard. We'll see if it works in the real world. Here is a screen shot for those that can't make the link with my data work. The webside url is [url]http://www.not2fast.com/turbo/glossary/turbo_calc.shtml[/url]. [ATTACH=full]86294[/ATTACH] Cheers ! [/QUOTE]