As Phil says, I would check custom made aluminium radiators. The company I'm working for in France has been importing
Pace Products radiators (and intercoolers) for years, and they are very good quality (TIG welder there are artists). Now we turned to
PWR as the technical advice is better. The products are extremely well designed, a lot of good engineering solutions. Don't think the best for your powerful engine will be a radiator as large as it can possibly fits under your nose cone. Even high level racers have a tendency to oversize the radiator for no good reason. An oversized radiator carries more water than the engine needs, and it is useless weight in board the car. People at PWR will tell you the ideal size/thickness you need for your engine. They are spot on, we never had any bad surprise on their advices. And if you want to combine it with an Intercooler, there will be no problem for them to design a complete unit.
Of course, custom made aluminium radiators are not cheap, that is the big down side.
Personally, I installed a Mercedes 190 (I will run a Pinto 2.0i), as the compact size combined with a good thickness is supposed to make it cope with 2.0L engines (well, Mercedes 190E engine is a 2.0L). Some pictures here if you want to see by yourself:
http://vouchtroadster.blogspot.se/20...-radiator.html
Please keep us posted of what you decide, I'm very interested.
Thank you.
Sylvain