Difference between revisions of "Electronics"

Revision as of 22:00, 25 November 2011

Battery

Currently a stockish battery (?). What are good options here? Odyssey makes several options, but there has to be better nowadays.

What does the current battery weigh?

Likely choice:

• Braille B106: AGM, 6.9 lb, 10 Amp/Hr, 210 CCA, 527 PCA, http://www.amazon.com/Braille-Battery-B106-Lightweight-Racing/dp/B004DDI12O 140$+FS]
• B106 Mount: Aluminum, 55$+FS

Others:

• Mueller MotorWerks EVO2: Lithium, 3 lb, 28 Ah, 550CCA, 269$ -- Looks like potentially a really good option. How is it so cheap for so effective a LiIon battery? Something has to be fishy. Try to read up more on it...
• GRRReen 20Ah: Lithium, 7.25 lb, 20Ah, 330CCA, 289$

Ridiculously expensive but awesome:

• Braille ML9C: Li-Ion, 3.7 lb, 36 Amp/Hr, 612 PCA, 950$
• Braille ML14C: Li-Ion, 4.5 lb, 42 Amp/Hr, 773 PCA / 548 CA, 1250$
• Voltphreaks VPH300: Lithium, 2.75 lbs, 340 CA, 140 CCA, 7Ah, 789$
• Voltphreaks VPH450: Lithium, 3.75 lbs, 500 CA, 200 CCA, 9Ah, 929$
• Voltphreaks VPH750: Lithium, 5.5 lbs, 650 CA, 260 CCA, 16Ah, 1300$

NASIOC Battery Post with a bunch of other misc batteries.

Need to buy a trickle charger too.

Does it make sense to weigh the battery cable that runs along the PPF? With a tiny lightweight battery like this, it might make more weight sense to put the battery up nearer/in the engine bay and drop the 10 feet of thick copper cable. ST and SP both allow free relocation of the battery.

There's a rumor that the Deka ETX9 is the same battery as the Braille B106 (that the Braille is a rebadged Deka). The cranking specs are quite a bit different, but the ETX9 is ~55$ and the weight is the same. Some people on Miata.net have run them successfully, but I'm skeptical. Maybe start with the B106 and if it dies too quickly just get Dekas to replace them?

Engine Management

Bought a MegasquirtPnP. It only supports batch fire injection and wasted spark ignition, but that should be fine for us for a while or possibly forever. I'll eventually need to buy a KnockSenseMS board for knock control with it, but that can wait until I get the supercharger started.

I was reading about the cam angle sensor, and one guy at least has seen up to 5 degrees of spark scatter due to belt stretch or other reasons. That seems on the excessive end, but it might be a good excuse to upgrade to an AEM or something similar down the line. Removing the CAS is probably worth a few pounds, and running as much boost as we're running, even a few degrees of spark scatter could cause major issues. The knock sensing on the MSPnP is also poor (the knocksense board I mean) whereas the AEM has a much better system. See how the MSPnP works, and just remember that there's other options available (AEM, 1000$) as necessary.

Traction Control/Launch Control

Picked up the Race Logic RLTC6AL from PDM Motorsports for 1100$ CAD. It will integrate with the existing electronics in minutes using Kyle's patch cable to avoid hacking up the main harness. Don's set it up on a bunch of cars so he'll be a good resource too. Apparently Strelniks runs the same system.

Wideband

Bought a Zeitronix Zt-3, the same thing I've been using with pretty good success on the KLiata. The MS3 seems to support it just fine.

DAQ/Instrument Panel

Buying an Evo4 + MyChron3 for now. It can read from the MegasquirtPnP (MS1) via RS232. It supports as much data as we want down the road -- can do 12 tire temp inputs, 4 shock pots @ 1000Hz, and our other analog pressure/temperature inputs.

Tire Temps

Opti-Grip seems like a surprisingly affordable package. Would need to figure out how to integrate it into existing datalogging, but it could be neat...

Wiring Harnesses

Body Harness

We can remove the airbag and radio circuits in entirety. We can remove the power windows and hard top heater wiring because it wasn't present on the '90. Remember to tear out the antenna cable from the PPF line.

This post says that the CA body harness is different to deal with the sequential injection. Not surprising. Looks like we need all the harnesses off the old car, and hope that the stuff under the electrical tape isn't too terrifying. The front harness we want is NA37-67-010B (california w/ABS).

Engine Harness

• Tear out the AFM wiring while the harness is apart
• Figure out where the battery cable enters the main harness
• Learn what all the various relays against the walls do and if any can be eliminated

Dash Harness

The harness we want is NA02-67-030N that has ABS wiring. Flyin Miata has one for 50$ if we buy a car without ABS and need to retrofit.

Injection Harness

Sequential CA cars use a different injection harness: NA36-67-080. Steal it off the current car.