I had that VR bookmarked long ago, but gave up when I realized the engine computer would fire up the check engine light and goto default A/F mixture and spark timing, killing MPGs
Thankfully someone else figured out how to trick the engine computer, and I paid some 30$ for what is a 3 dollar resistor. The 10 OHM stamp was filed off.
I thought the 10 OHM resistor was for tricking the ECM into thinking it was still attached to an externally regulated alternator. What I do know is If the ECM's VR would choose 13.7 and I've chosen 14.8v, 30 seconds later the CEL does come on. The light will go out next engine startup, but the code is stored and it defaults to preprogrammed AF mixture and spark timing and MPG suffers. Solution is to reset ECM and then, 14.7v max.
I have put my clampmeter over the 10OHM resistor leads at different voltages with a near fully charged battery, but did not record the data, but it did change as I spun the potentiometer.
My 50 watt resistor does get hot, so I thermal epoxied another heatsink to it. I wonder if the VR in the ECM is getting as hot when bypassed.
I really love being able to nearly instantly achieve absorption voltage, when the RPMS are there, or spin the dial up and watch the amps increase with my digital hall effect ammeter whose sensor os now on a + battery cable, previously on the alternator output(+).
It is a crime when a depleted battery in desparate need of maximum recharge when driving, is only allowed 13.7v, like some some of sick battery torture.
Also the 14.9v My ECM always sought on cold startup for a few minutes is a bit ridiculous. My ECm would occasionaly decide to hit this voltage well after driving for a bit and when the battery was already fully charged and hot too, when 13.7v was more appropriate. I wonder how the ECM chooses its voltage. My engine actually sucks some underhood airflow through the ECM.
A few weeks back, My battery was accepting 29 amps at 14.7v when I parked and kept idling. I slowly lowered voltage to 13.6v, and about 30 seconds later amps settled at 9.2 amps. ~66% more amperage delivered into my ~ 75% charged AGM battery at 14.7 compared to 13.6v.
I've also lowered voltage when a damp cold drive belt was squealing when accellerating when feeding a very depleted battery 70+ amps.
My Transpo540HD has an additional heatsink added to its underside, and later I added a 60MM fan to that, I hope it proves durable. it has been in operation for 14 months or so.
I am assuming if it fails I could hook up the enginne comuter ECM in an emergency, but another Transpo540HD would be an easier fix. Guess I should carry a backup, and modify it for the remote potentiometer so it would be plug and play.
The VR modification is pretty much my favorite electrical modification, but the Meanwell rsp-500-15 with the remote 10 turn pot, extra heatsinking and venitaltion, will seek any voltage between 13.12 and 19.23 with 40 available amps and has been in regular use since 9/14.
Both made possible by the OP
