Hi Steve,
I can´t remember the guys´name, but he is a member of this forum. He has done the GM V6 swap, but said that if he were to do it again, he´d use the Ford 2.8 V6 instead, because it is a ton easier to swap. He had to change the steering system to a rack and pinion system in order to make it fit. If I were to go to all that trouble, I would swap in a Ford small block, because you´ll need to do as much work as if you did the GM V6.
Seriously? Is this diatribe still going on here? Completely not true! I have done a GM V6 swap with the ford T5 in my 62. It's a beautiful swap that looks like it was meant to be in there!
http://www.lx9alpine.com/lx9-v6.html
The engine is an LX9 3.5 liter that in stock form produces 200HP and 220 ft lbs of torque, before headers and any other modifications. The 3100, 3400, and 3500 engines were placed in many makes and models of GM cars and can be found for next to nothing. There is a healthy aftermarket for high performance parts and a large community of support.
http://www.britishcarconversions.com/
https://wot-tech.com/3500-lx9-2004-2006.html#4
It allows for the stock Alpine steering (with the same steering center link modification the Ford V6 swaps require) and has no interference from the engine or headers allowing full range steering lock to lock.
http://www.lx9alpine.com/transmission.html
It requires custom headers like other swaps.
http://www.lx9alpine.com/headers.html
The Ford Cologne V6 is a heavy, inconvenient, inefficient, under-performing dinosaur. The only reason people use it is because a kit is sporadically available and it has been highly publicized as the only alternative. For a long time it was, and it could be a wonderful improvement over stock. But that was the distant past and this misinformation is consistently being presented as fact from the producer of that kit. (With the obvious motivations that he stands to loose out on your money, some false self esteem, and his social status as the unofficial leader of the "dark side". It's time for the modified Alpine community to become "Enlightened"!).
The MG community has fully embraced this engine for swaps and has already worked out all the parts and pieces to swap the LX9 3500 in and get it running. The parts of the swap that are unique to our Alpines are custom motor mounts, (which work with an unmodified cross-member, using the original motor mount holes), custom headers, and the previously mentioned steering center link modification.
If all you want is more power or more reliable power, all the numbers point to a modern aluminum block four cylinder swap. Much easier and straight forward than other alternatives.
If you want a beautiful, high performance drive train setup with the reliability and efficiency of a modern engine in stock form, or a lighter, quicker car that will outrun and out corner many Tigers, the GM 3500 is a great place to start looking.
https://en.wikipedia.org/wiki/GM_High_Value_engine#LX9