Plexus posted:

$2200?!? Ouch, no way: thanks, but I've found a nice way to do it. Bosch make a universal 120A alternator which I've picked up brand new for $200 (trade price - I design electronics so I can get away with it). Throw the body away (my alternator has two bottom mounting flanges, the Bosch unit has one fat one) and use a body from say a late-model Ford one to get around the lower mount problem, change the rectifier assembly for an early one to get around the differences in the post mounting points, whack the pulley from my old ND alternator on, and presto! For a grand total of just $250 I have a brand spanking new 120A charging system. I'm fitting a second battery and knocking up a MOSFET controller to charge it. Running all my lighting will definitely kill the existing 50A unit I have (actually, I thought it was only 30-40A, but even 50A is asthmatic). Even now, with 400W of forward lighting and 100W of rear, plus the 100W hand-held spotlight out the side window, the current (pardon the pun) charging system just doesn't cut it. You can watch the battery voltage drop like the resale value of a Range Rover (whoops, did *I* say that?). When the forward lighting goes to 600W next week, it would need an extra 10 hamsters running on treadmills to power it up.

Plexus posted:

Yes, I know the Bosch has 8. We added a couple of extra diodes before fitting it all together to make the new rectifier plate "proper", so no problem. We used a housing to suit late model Mitsubishi Sigmas - only needed to take some thickness off the LandCruiser's original mounting plate with the angle grinder; then it bolted straight in. Only niggly I found after installing it tonight was that it needs one quick push on the throttle to take it to around 1700 RPM once you've started the engine to kick in the charge relay - after that, it holds and it's fine. Obviously the shaft speed is too slow at the 650RPM idle, so tomorrow we're going to get a much smaller pulley and put that on, to get the alternator spinning faster. To get around the problem of the FJ's relatively wide drive belt, we're going to use a split pulley, and make up the width by packing internal washers between the halves.

Plexus posted:

OK here's our final configuration:
ended up using the body from a Nissan Pulsar (late model 1988-1992) and changed the regulator to the Bosch RE60 unit. Light never goes on (it did before) so low-speed performance is great. Charges almost at the low 650RPM idle. Increase the engine speed to 800 RPM and it charges right up, even with 700W of lighting going. We measured 13.7 volts at this point - great!

Plexus posted:

No, the *housing* is from a late model Pulsar. That's all. The rectifier is the original one that came with the Bosch. It's passed the test: we came home from Stockton Beach at 1am this morning and the system had no problem in keeping up with a grand total of 1000W of lighting.