I just pulled the PC925 out of my car and replaced it with a traditional Group 42 lead acid battery.
Couple things that I noticed - the car cranks a little faster.
At idle with lights in wipers running the car sits proudly at ~12.5-13 volts as opposed to the 10.5-11 volts with the 925.
For those wondering about my alternator - I totally went through my electrical system in 2018 when the car stranded me during a drive. New Alternator, alt harness, VR, relay board, cleaned grounds - it was a journey! I can say with some certainty that my charging system is working well.
Here is a thread with information about the LI batteries, draw etc in a 914.
http://www.914world.com/bbs2/index.php?showtopic=342693If you only drive on sunny days, or live in a place like California where you never really need to use your wipers and it does not get very cold, the batteries like the 924, 925 are probably just fine. But my experience is that if you get caught in a prolonged rainstorm, the 925 does not have the AH to keep up. The wipers (at least my wipers) draw a lot of power.
Another issue that I have the you guys may not - especially if you are carbed. I have modern EFI, and it gets funky if voltage drops. With carbs, you could likely run all day at 10.5 volts and be just fine. I have no real experience driving a 914 with stock injection, so have no understanding of how it would behave. But I know when my car was carbed, as long as I had enough power to run the fuel pump and ignition, the car would go just fine.
I'll keep my 925 and swap it in for AX days and stuff like that, but the Group 42 battery (IMHO) makes a better option for varied street driving.
To each their own,
Zach