I haved searched but my internet connection is waaaay to slow right now and is driving me crazy so i figured this would be much faster for me!! But i was wondering if there is a problem putting an s5 alt on an s4? Are there charging problems etc? my friend did this and is having problems and im wondering if this couldbe the problem or if he has a drain problem somewhere else. Any help would be great, Thanks.

 

Um I don't even think the plugs are the same? I know an S4 alt can go on a 1st gen, but some work would be required to affix a S6 or S5 alt on either of the other too. It is a better unit and worth it, in my opinion. I need more info. Please tell me what you did. Give me a mental picture.

 

You can fit an s5 or s6 alt on s4's, but you have to do some re-wiring. There is actually a thread on the first page about this - its called something about the FD alt plug. The s5 alt wires up exactly like the FD alt.

 

ah must not be then, he must not know what he's talking about then

 

Well, just make sure he has it wired up right.

 

Mechanically this is a direct swap, but some electrical changes need to be made. Here's all the info you need to do this:

Alternator schematics: https://www.rx7club.com/attachment.p...hmentid=199213
Alternator pin-outs: https://www.rx7club.com/attachment.p...hmentid=170065

 

What NZ posted is exactly whats in that thread I told you about, btw.

 

*******my friend did this and is having problems and im wondering ************

Most likely his only problem is, he NEEDS to run a wire from a constant, 24hrs a day source of 12vdc to the alternator, to what they call the *S* terminal on the back of the alternator.

IF the alternators regulator does not see that all the time, then the batt will get discharged over a short period of time. Like a day or so. He can't use the switched 12vdc source that the series four plug uses. Won't work. It's a Switched 12vdc. No good.

Pay close attention to the KEY WAY on the alternators jack so you will know which is the *S* terminal.

By the way, there is an outfit called SunCoast that sells alternators for series five. When you get the alternator it has a pigtail for that plug with the *L* and *S* terminals. It's about four inches long with a plug on each end. That pigtail gives you some options on how to connect it to a series four harness. The plugs on each end are made to fit the series five, but it still gives you *options* on how to connect it to a series four.

I saw this alternator on CarParts.com, that JCWHITNEY outfit.

 

ok thanks ill check and see what he did and make everything the way its supposed to be, because his car is doing exactly what HAILERS said and loosing charge over short periods of time. Also sometimes even when he's driving the voltage shows that it drops to like 10v sometimes even lower, but if he revs a lot or goes quickly at higher rpms it will jump back up to 12...whats up with that?

 

Sorry for reviving this thread. I sourced an S5 T2 alternator from an english made convertible, now i want to install IT in my european made S4 NA. Both connectors have 2 wires. What exactly am i doing with the last Wire og i run 12v constant to the S terminal of the new alternator ?

 

Sorry for reviving this thread. I sourced an S5 T2 alternator from an english made convertible, now i want to install IT in my european made S4 NA. Both connectors have 2 wires. What exactly am i doing with the last Wire og i run 12v constant to the S terminal of the new alternator ?