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-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   FD Alternator Swap (https://www.rx7club.com/1st-generation-specific-1979-1985-18/fd-alternator-swap-936492/)

kc0stp 01-03-11 07:33 PM

FD Alternator Swap
 
This may be a dumb question but what all is involved in putting an FD alternator in a 1st gen? (Carb'd) Stright bolt in, pulley swap etc

wmelon137 01-04-11 08:23 AM

Some rewiring will be involved.

an S4 alternator is a straight swap. Here's an image describing the wiring changes you'd need to make to use an S5 or FD alt.
https://www.rx7club.com/attachment.p...hmentid=146552

image stolen from the 2nd gen FAQ.

kc0stp 01-04-11 09:15 AM

S4 from a 2nd gen? Whats the specs on it? (Mainly after easy/cheap swap to help with increased draw from swapping to Elec rad fan on the race car)

rxtasy3 01-04-11 12:34 PM

my stock alt works just fine with elec fan.

Crispin38 01-04-11 12:44 PM


Originally Posted by rxtasy3 (Post 10397585)
my stock alt works just fine with elec fan.

Yeah. I have a stock reman alternator in mine and it runs all my accesories fine. Including my electric fan, and my sound system. I've got a amp that's puling a lot of power and it's powering a 15" inch sub. Stock alternator should do, but, and S4 alternator swap is extremely simple. Where as S5 is a different story.

Twilightoptics 01-04-11 02:25 PM

Stock reman in mine couldn't power everything in the Northwest with defrost on, blower on, wipers on, etc. S5 is a bolt in swap. You need to wire as above and get the std pigtail. Turbo II alternators are 80amp, non-turbos are 70amp.

I'm happy with my Isuzu 115amp :O)

gsl-se addict 01-04-11 02:29 PM

In addition to the wiring change, the FD alt (if you went that route) would also need the pulley swapped.

I went with the S5 alt and I am very happy with it.

Twilightoptics 01-04-11 02:47 PM

Opps forgot to add the pulley swap!

88SE_HI 01-04-11 05:44 PM

It would be a little more complicated if your 1st gen had an external regulator.

DriveFast7 01-04-11 06:02 PM

Got the FD alt with dual sheave pulley to work on my REPU. It's great. Be sure to wire the exciter wire up to a constant on +12 volt source otherwise it'll slowly, quietly drain the battery when you shut the truck....er car off.

Don't get the steel dodge caravan pulley some guys sell. It's larger diameter than FD so it'll underdrive the alt. Low voltage at idle especially. Get the aluminum dual sheave one I think japan2la sells. Mazdatrix has them too.

Japan2LA 01-04-11 08:10 PM

The pulley is right here:

https://www.rx7club.com/showthread.p...light=japan2La

BLUE
BLACK
Purple
Machine Finish

ALL in instock now..

DriveFast7 01-04-11 08:31 PM


Originally Posted by Japan2LA (Post 10398267)
The pulley is right here:

https://www.rx7club.com/showthread.p...light=japan2La

BLUE
BLACK
Purple
Machine Finish

ALL in instock now..


And I like it!


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