Well I had issues with power steering and part of the comprehensive diagnosis was to check the Amp current and so, I reached the colocalisation that the OEM alternator is rubbish and barely
can even cope with OEM demands.
For battery, I am using EFB as I am not willing to mess with the basics of the system to have AGM or another type of battery.
So all sorts of self-regulation, self-exciting self-working alternators are ruled out.

I had had a fair share of searching until I found this product, which made me able to keep my OEM charging system.
Based on my use and engine RPM, I went with LMA620-MHO 'Square 2 Pin' 250A which gave most of power on lower PRM in comparison with 320A which needs more rev to produce the same.
Price was over £900 is not cheap by any means, 320A is around £100 more but really needs to rev to shine,

Installation was not as straightforward as I had anticipated as the PCV pipe almost hit the alternator housing, need to say the serpentine belt I receive is a tad longer than OEM which doesn't help either.

 

Nice write up and pics. How is the alternator holding up and was it worth the extra cash? I recently replaced mine with a low mileage (58K) one from a wrecked rx8 at the junk yard. After searching many forums it was a general consensus that the stock oem one's are the best way to go instead of the aftermarket one's sold at the local part stores. When installing everything back, i went ahead and did the Big 3 upgrade and noticed the idle and startup to be smoother than before. I see that you upgraded the gauge of wire from the battery to positive battery post. Did you also upgrade the ground cable points?

 

Well, it has been a while, pleased with my decision.

I have another rebuilt OEM alternator, which was rebuilt way back in COVID-19, and I coloured it blue.
The issue with the OEM setup is not adequate for the basic needs of the car itself.

The electric power steering is a very power-hungry setup. Be my gauss and do your reading.
Since I have the upgraded alternative, I can say the power steering is working better.
With OEM alternator, the initial movement is the same, whereas the mid-way of the stork, it would fade.

I haven't done big 3 as people call it the big 3 perse, it is nothing fancy no zero AWG, used a quality 4 AWG alternator to the battery directly,
negative from the battery to everywhere.