Turbo Maps

While researching doing a turbo...I found one of the hardest things to do is choose the actual turbo. It is all based on turbo maps. These are charts put out by the turbo manufacturer the show the islands of efficiencies. These are done with the x-axis showing the lbs/min air flow and the y-axis pressure ratio. Well, How the hell do you figure out your engines pressure ratio and air flow? Lots of math. You need to know the cid, max rpm, volumetric efficiency, max boost and intake air temp in order to arrive at the lbs/min and pressure ratio...then map it to the compressor map.

So, like any good computer geek, I wrote a JavaScript program to figure this all out and do the mapping. I can feed it any specs and give it a map and have it mark where that set of specs falls. I might post it here someday...but it is of little use without being able to upload your particular map so..for now...here is the output. The red X is where my motor lands with a boost of 10psi and a max rpm of 5000. It also falls in the islands of efficiency for most of the rpm range. As well as up to 18 lbs boost and up to 6300 rpms