I bought some 0awg wire and have been going crazy on my other vehicles upgrading grounds and alternator wiring. I still have quite a bit left over and did the grounds on the Rx7. So my question..

Is it worth upgrading the stock alternator wiring on the 7? (I assume it is, but is 0awg overkill?) Would I have to go to a 2nd gen fuse block? Any help or insight would be much appreciated. I haven't had any luck searching on this topic!

 

Battery cable to starter and ground, i used 0 gauge. AlternTor to fc.fuse block, im using. 8 gauge stereo amp wire

 

Same. 8ga stereo wire for the excess in strands carries the load better. I've also got a 130a giant alternator on there too. No problems with it with the power loads all cranked on.

Can't talk about gains, because I added grounds, Mazda pickup (fc like) engine fuse box, used welding cable for heavy power/grounds and did the ignition switch relay mod. After that, everything works better and my windows rull up/down like a new car.

 

Awesome. Thanks!

 

Upgrading my battery and ground wires was one of the most amazing (and unexpected) night/day changes I made to my car. Starter cranking speed went way up and the car became much easier to start. Flooding became pretty much a non-issue (or at least, bloody easy to deal with). I also saw a lot less misfiring, likely because of stronger charging and more power available to the plugs. I did the FD Alt swap shortly thereafter and that helped, too.

When I stopped to think about it, it made a lot of sense. These cars have been sitting around for 25+ years. The wires are old, the grounds slightly rusty, and what was "adequate" for moving power around when the car was new became "barely able to function".

So, in short, do it! You definitely won't regret it.

 

The original cables are also made of aluminum strands, which corrode fast and conduct like crap. Welding cable is the best. GREAT insulation and way more strands which increase the surface area and cause less resistance/voltage drop across the length over say your napa replacement. The only catch is, you have to solder the ends on yourself. A vice and propane torch and it's a breeze.

 

This is the next thing on my to do list for my SA. I know it needs it, badly. I was looking to either use the replacement cables from a parts store, or using the 0 gauge they sell by the foot, but I welding wire sounds interesting. For those of you who have used welding wire, where are you purchasing it?

 

I can't speak for the welding wire, but I was able to get some 0 gauge copper wire from the local car parts store for next to nothing and it did the job beautifully. Copper is a better conductor than aluminum, the wire's thicker than the stock wires were, and if they still manage to corrode internally after a decade I don't care because it was less than $20 for everything and took an afternoon. That includes brand new battery terminal connectors, the solder that I used when I installed my FC Fuse box, heat-shrink and the wires themselves!

Jon

 

Ground upgrade has made one immediate difference so far. I thought my alternator was on its way out because my voltage gauge would always drop off a bit till warmed up, no longer does that anymore! I have not touched the alternator wire yet and I'm glad for the extra feedback. I can't wait though to see what that improves.

Also, I just bought my 0awg wire off ebay... doesn't seem to be bad quality. I am not aware of any issues with wire from ebay. I have bought a starter cable "upgrade" from autozone (4 gauge, I believe) and am not a fan of it. but it does serve its purpose.

 

Welding cable you can get by the foot at any welding supply store. And the terminal ends you get a parts stores, maybe even the welding store as most welders use large ring terminals also.

 

Is that the taurus alternator?
How is it over 8 k rpm? I have been wanting to upgrade but not sure if it can handle 8k+ rpm.

 

It's a 2010 Isuzu NPR diesel alternator. It's massive. To get idle speed charging right I had to use the smaller FD dual pulley. No problem at 7500 which is as high as I take my little 12a.

The only cons: It's HUGE, and when EVERYTHING is on, it's a noticable drag at idle similar to A/C but not bad enough to need idle compensation.

Uses the S5 connector and wiring. To fit the slotted mount, straighten the curved bracket and it fit in like a charm.

 

Thanks bro. I will try the taurus alt, will use lots of lock tite on the pulley bolt since im rev happy lol

 

If you are going to upgrade your electrical system, check out this thread. Might be of some help.

https://www.rx7club.com/1st-generation-specific-1979-1985-18/130-amp-alternator-upgrade-891145/

In my opinion, the stock 7 doesn`t have much in the way of electrical headroom. ....at least for the earlier years it didn`t. Add a few accessories and things aren`t great. Having more supply than demand is always a good thing.

 

so how was at it redline? thats my concern as non-RX cars do not rev past 8k. I have the taurus alternator already, got it during junkyards 50% off during new year sale, $10 is nothing for testing purposes.

 

Works fine so far. Hardly redline my ride. No need to with the turbocharger. Your pulley ratios will determine what RPM your alternator sees so you can put something together that will work and still be within the max limits for the alternator.

 

I did my test fitting but for those who are still using a distributor, as suppose to a CAS, the taurus alternator upgrade is not going to be an easy project as the distributor cap gets on the way. I need to spend more time designing the bracket over the water pump housing as this alternator is very bulky. I think a mid-90s toyota 140amp alternator is a better choice as it the same size as a FB alt. cant wait for the next 3-day weeend