>I'm considering having my current 2 core radiator converted to a 3 core
> & have the following questions:
> > 1) Should it cost about $150?? or more?
> > 2) Is there a source that sells them new (I'd rather have two);
> would appreciate if anybody could share radiator mod experience
I had a 3 tube core installed in my S III radiator about 8 years ago in Albuquerque. I paid around $120. Your cost sounds like it's in the ballpark. It could be you could strike a deal and get two done cheaper. The only aftermarket radiators I am aware of are the ones for the Tiger, and I'm not sure the inlet and outlet are in the same position as the Alpine. Most of the ones I've seen start at over $300. Some have aluminum cores, and are aparently not easy to clean or repair.
I can enthusiastically recommend this mod. It makes a real difference in cooling. Remember, though, that Alpine radiators don't cool well unless you're at speed. Be sure to install an electric fan ahead of the radiator, and put it on a panel switch or thermostat. You can buy a compact aftermarket fan at an auto parts store for $50+, or check the junkyard. I paid $20 for an older (early '80s?) Honda Civic fan that works just fine after 8 years. I used longer bolts to mount the radiator and bolted the fan on to those after I modified the mounting brackets some. Good luck.
Rex Funk