You are correct, the design of the core is everything and like I mentioned previously, i have had no issues with quality of my ebay core. I have had no luck finding a well designed core on eBay they are all straight through fin design, if you know of one, please share.
I will be testing out some different core designs and endtank designs to see what works best before settling on a final design.
I plan to put together a piping kit that allows fitment of an evo 8 intercooler. If people want to use that kit with a used stock evo 8 intercooler that is fine. If they want to use the kit with an ebay evo 8 intercooler thats fine also. My point here is that I will only be offering the pipeing kit only which leaves the quality of the intercooler up to the end user.
I will also be offering a full bolt intercooler kit that will compete with what ETS has now discontinued. In order to do this I need a well designed core that performs like the ETS core. Like I have said before, I would like to keep the price low, but I have decided I am not going to sacrifice quality or performance. My main concern is offering a product that performs very well, since we no longer have the option of buying such a kit from ETS, and I beleive I can get close to this and save everyone some money. If you are looking to save a few bucks then I will have the piping available to be used with an off the shelf ebay evo intercooler.
Horsepower ratings are generally only taking into account flow. Just because a motor produces 1000hp with a certain intercooler does not necessarily mean it is efficient at cooling. Intercooler's primary function are cooling, and having a straight through fin design that flows well with low back pressure is not going to cool as well as an intercooler with a staggered fin design. There must be a balance between the two.