"BEEFING UP" THE CHARGING SYSTEM

Difficulty? Easy

Total time: hour or two

Applications:  86-88 NA/Turbo, 89-91 NA/Turbo

The RX-7 is notorious for having a very weak alternator and charging system.  I don't remember what the output rating is on the alternator but it is barely adequate to charge the battery, let alone run any heavy duty stereo amps.  Basically all that is required is some 4 and 8 gauge wire, a good crimping tool, and a little time.

The principle is simple:  By doubling up the grounds from the engine to the battery, you increase the paths for current to flow.  Most people that have done these modifications (including me) have seen voltage readings taken at the battery raise ~1 to 1.5 volts.  This extra boost in voltage will help your battery and your alternator last longer by putting less of a strain on the whole system...

One other side effect is that for some people, re-grounding the engine for has eliminated the 3800 RPM hesitation that occurs when the secondary injectors kick in.

GET TO WORK:

For all these connections I used 8 gauge wire that was left over from my stereo install.  That takes me to my next point:  Your going to need new battery terminals in order to run the extra wires from the battery to various points on the car.  Since I already had the stereo upgrade, I already had upgraded terminals that allow for (2) 4-gauge connections, and (4) 8-gauge connections on both the positive and negative terminals of the battery.  This might be a little excessive for most, so I would recommend going to Pep Boys and get some new terminals that allow for extra wire connections.

You can see my terminals here:

The Extra Grounds:

1)    Run one ground wire from the negative terminal battery to the chassis.  I ran this wire to the bolts that hold the leading coil pack.  I figured this is a good spot because your ignition needs a good ground!

2)    The second ground I ran was from a bolt on the firewall to the back of the intake manifold.  I ran this one in order to improve the ground to the Primary injectors.

3)    If you have a problem with the starter turning slowly, you might also want to consider an extra 4-gauge wire from the battery directly to the starter.  I didn't do this one yet because I've never had a starter problem, but some people have reported that the ground wire to the starter corrodes inside.  If you do the starter upgrade, you will HAVE to use 4-gauge wire for this one!  8-gauge can't handle the cranking amps...

The Extra Positive Lead:

1)    This is one extra wire that runs from the positive post on the alternator, that runs directly to the positive terminal on the battery.