oreo

^Thanks!

I have tested the cold plate with the 12 peltier devices. As near as I can tell it's in the ballpark of what I expected cooling wise.
I have really no idea if this thing is over designed. I suspect it is, but still plan on adding the additional 12 peltiers to it.
I don't have to run them all if I don't need to.

Anyway, power is a concern. At 14.6v, the 12 peltiers stabilize at about 24 amps, and the fan is drawing 21 amps.
So all in, if my electrical system were somehow able to maintain 14.6v we are talking about 70amps, or 1.4hp.
I suspect (hope) this will be a peak requirement, with much lower draw once the cooling water is brought down to working temp.

The issue with my calculations, is that the peltier heat pumping capability changes with the temperature differential between the hot and cold sides of the device.
So I need the heatsink to be as close to ambient as possible, and I need the water to be as close in temp as the cold side as possible.
If I can maintain a 40C differential at 14.6v the devices should pump ~250watts
If I can maintain a 30C differential at 14.6v, the devices should pump ~550watts
If I can maintain only a 50C differential at 14.6v, the devices will only pump ~70watts.
A person at rest, generates ~100w.

So a lot of uncertainty here.
Anyway, I have at least a month here before things even start to warm up so I can effectively test this.

oreo

Didn't use the cool shirt last season, because the temperature here did not get as hot as normal. It seems that most other places were
getting tortured with heat, so we lucked out. I am thinking I will be needing it this summer.

My battery was on it's last legs and I was planning on building a LTO or Lipo4 battery with individual cells. I then found that Batteryhookup.com was
selling slightly used NEC 35AH Lipo4 batteries that had maximum charge/discharge of 210a. Since they were only 95$ and this should be enough current to start a Miata, I
bought one. It turns out it has no issues cranking the Miata under normal circumstances. During the summer my master clutch cylinder failed, and I had to start the car in first gear quite a lot trying to get the car home.
On a few instances, the BMS in the battery decided not go along with it, but a subsequent retry seemed to always work.

Of course you can't charge Lipo4 batteries when it is below 0C, so I purchased a battery blanket. I rarely run the car when it is cold so that seemed like a
reasonable option.

The battery is currently at 93% capacity. So should give me many decades of use.

I also purchased a 93 RX7 upgraded 160A alternator. Time will tell if it was wise to get the higher amps version, because there are lots of false claims being made out there.
I still need to install this, but soon. I am using 1/0 CCA wire with a 150A fuse that I still need to heat shrink.

So the last few years, my supercharger has been leaking at the snout seal. Last year I replaced the seal, but no significant improvement.
I knew the shaft was worn, so I ordered a Speedi-sleeve, which is a thin sleeve you press over the shaft. This makes the shaft a bit larger than nominal
however many seals can cope with that. (The sleeve and install tool are at the bottom right of the below picture).

After getting the sleeve in and seeing how the front assembly goes together, I was not confident I could install a PTFE seal over it without damaging the seal. I have been using PTFE seals due to
their higher RPM rating. Another issue I discovered, when trying to order a new PTFE seal is that no-one seems to make them with an OD of 52mm (now a max of 47mm), which is what I need to fit the supercharger case.
Fortunately, I looked through my used supercharger stuff, and found a fairly new shaft in there. I can't measure any wear on it.
I ordered the 47mm OD sleeve and had a steel part machined to take up the difference between 47 and 52mm. This should solve things.

The old shaft was worn down .006" in diameter!



Ready for re-installation with 47mm OD seal and a adapter ring to fill the gap to 52mm.


Still have quite a few things I want to get done before summer. Lets see if the weather continues to be reasonable.

HarryB

Is that an energy storage battery? Interesting!

oreo

Yes, I have seen internal pictures of the construction and it looks like it will stand up to vibration, and of course being mounted in the trunk solves the heat issues.
It's the only energy storage battery I have found, which supports the currents needed to start a car. Unlike motorsports lithium batteries, the BMS in this battery will disconnect it if
you run the voltage down too far, or up too high.
The internal battery layout uses a 4s12P pack, using A123 ANR26650M1B cells, which are rated at 50A continuous current each. So the battery pack itself is rated at 600A continuous, while
the BMS limits things to 210Amps. These are excellent high discharge cells with good life. I have 2496 pcs of these cells in a solar battery and they have performed well.
NEC lists applications as Telecommunications, UPS systems, Medical equipment, off grid power and electric mobility.

Assuming I don't abuse it, it should last forever.

These NEC batteries are very expensive if purchased new. I have seen battery hookup selling them twice at $100 less 5%, and they don't stay in stock very long.

HarryB

Yeah, looked up the part number just now and was shocked! That was a good find, kudos.