After the failure of both my CDI and AC relay I was starting to suspect something electrical wasn't quite right. After reading about people having their batteries explode on them from over charging, I decided to get a plug in voltmeter so I could monitor my alternator voltage while driving. I was quite shocked to see values anywhere between 12.2V all the way to 17V even when just idling. Clearly the internal voltage regular in the original alternator was starting to fail. Thankfully, I had already anticipated having to replace the alternator so I already ordered a 175A high output alternator from Classic Retrofit months ago (they're generally backordered and ship from the UK). I dropped the car off with Speedsport Tuning on Saturday so they could get to work on it while I was at Watkins Glen with the Cayman.
High Output alternator mated to fan housing - 7-20-20
Original alternator vs new alternator - 7-20-20
This unit is a nice modern alternator based on units used on stop/start capable vehicles. It's 6-phase instead of 3-phase making it much more efficient and has an internal fan to keep it cool and includes thicker ground cable and power cable to the start motor. One of the major benefits to getting this upgrade out of the way besides reliability is that it opens up the door to maybe installing the Classic Retrofit electric AC conversion in the future for significantly better cabin cooling during the hot months.
Details on the high output alternator.
It's really quite a gorgeous piece and it's almost a shame that it's covered up inside the fan housing and shroud. It's designed by WOSP Performance in the UK for Classic Retrofit and these guys really know how to engineer stuff. Who doesn't like billet parts and well engineered products, right?
Classic Retrofit / WOSP Performance High Output Alternator
Classic Retrofit / WOSP Performance High Output Alternator
I liked their alternator design so much that I decided that if we're going through the trouble of doing the alternator, the next suspect old part that could leave me stranded was the old starter motor. Thankfully WOSP Performance also makes one that's not only high output but also half the weight of the stock starter motor. I think it's based off a Denso unit so you know it's going to very reliable.
WOSP Performance high output lightweight starter motor
WOSP Performance high output lightweight starter motor
New starter motor installed - 7-20-2020
The combination of the new alternator and new starter motor is perfect. The car starts up beautifully each time now and the voltage output is a consistent 14.0V maximum at any RPM above 3K (drops to around 13.2V at idle). Since I did an EFI conversion, I really think this stable voltage has helped it quite a bit as I've noticed the car runs smoother now. I presume those sensors feeding the ECU are behaving more predictably with the correct voltage.
While we were at it with electrical upgrades, I also got the Classic Retrofit rear fuse panel. It works the same was as the upgraded front panel but there are only 3 fuses in the rear. I just wanted to standardize on modern style fuses so they're easier to replace if needed.
Carmagic Bright White instrument cluster LEDs
I noticed a few weeks ago that some of the instrument cluster bulbs were dead or super dim. I'm a big fan of LEDs because they're brighter and draw less current. I picked up a set of bright white BA7 LEDs from Carmagic and swapped them in today. It really makes a big difference being able to see the gauges properly at night.
Fitting new LED instrument gauge bulbs
It's a little hard to tell since it was very bright out when I tested them but you can see that all the gauges are now properly illuminated.
All gauges lit up with LED bulbs
All gauges lit up with LED bulbs
I actually ordered the Carmagic LED kit upgrade for the exterior bulbs too but just didn't want to tackle doing that today since it was too hot.
I think that completes all the major mechanical upgrades to the car. I've got some minor cosmetic things and new, lightweight battery to install but now we can move onto paint. I also finally got to see my friends over at K2 Auto to chat about our game plan for this car. We're doing a windows out respray plus a few other things. They understand what these passion projects mean to me (just look at what they did to Bumblestook a few years ago) and I trust they'll do an equal, if not better, job on my 911.
