Think the cp3k from fleece is good enough for 650? I guess when I want to go full big I can just add another cp3
The CP3K is enough for 650RWHP, but would be near its limitations on smaller injectors and a single turbo. If that's the max you would ever expect to make it would be great! Otherwise, the PowerFlo 750 which would be equivalent to an "85%" over CP3 would be what you need.
Quick crash course: CP3's are displacement pumps, like an air compressor. In order to deliver more fuel (quantity), in order to support more horsepower, you have to increase the displacement of the pump.
So... A Modified CP3 like the CP3K is a stock displacement pump. It is modified so that it can deliver full quantities (Displacement) over 3000 RPM. It does not displace more fuel, therefore technically will not support more HP under 3000 RPM than a stock LBZ CP3. Same goes for ALL "Modified, Stock Stroke CP3's". The benefit is beyond 3000 RPM. Assuming you have the air flow to support more HP, the CP3K will continue to provide Max pressure to either maintain peak HP or make more HP beyond 3000 RPM.
An "85%" over CP3, which in its title is a LIE, is generally a 10mm stroke pump. Stock is 8.5mm. Quick math says that is not a 85% gain in displacement. In a 100% Efficient world, which a CP3 is not 100% efficient, that's only 15% bigger.
If a Stock LBZ CP3 will make 650 RWHP, and if we gained 15% in displacement by stroking it, that gains us just shy of 100HP. 97 to be exact. Which ironically is why the PowerFlo 750, which is a 10mm stroked CP3 is rated for a reliable and repeatable 750 RWHP with proper supporting mods.
Maybe not so quick, but if you understand all of that, then you can now make more educated decision as to how to spend your money.
Heres the easy button:
http://fleeceperformance.com/fuel-system/injection-pumps.html
Caleb