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Hi guys. Just did a 100A alternator swap if anyone is interested. Sadly no pix. A wall of text though.
I was given a stock 100A one from a mazda FD rx7.
I currently have a carby sohc 16v b6. The b3 will basically be the same. Twin cam B6, Bp ect may be different.
The fd unit has a ribbed belt, you need to swap in your old v belt pulley if running one. I'm guessing ribbed belt guys won't need to swap any thing.
To swap the pulleys, you will need to drill the center out from 15, to 17mm after Using a rattle gun to remove both pulleys.
The pulley type on mine was a 3 piece. Almost like 2 big washers to make the v and a spacer in the back.
I used a mates lathe to drill out all 3 pieces, from 15mm to 17mm.
Put the drilled out pulley on the fd alternator with a rattle gun.
You will need to change out the bottom securing bolt on the new alternator because it enters from the wrong side.
Drive the captured nut on the bottom bracket towards the center of the 2 lugs to drive out the bushing and captured nut. Put the bush back in . You will need a new longer m10 bolt and nut for that becuase the fd one isn't threaded now. I found one with a head that was the right size to fit where the old nut went.
You will need an new m8 nut and bolt for the top of the alternator because it is not threaded.
The stock harness will plug in , but the positive crimp lug will need drilling out from 6mm to 8mm. I will be upgrading mine to 25mm2 welding cable. The negitive has already been done with it last week.
The tensioning arm will need a shave on the bottom to clear the alternator . It will be 2mm or 3mm.
To make it easier Put the belts on all pulleys before bolting it in.
With that wall of text done , a few other thoughts.
A fc rx7 has the v belt already there. It is 80A stock. It may be the same. I don't know the pulley sizes. I compared lug distances from ebay descriptions and posts on mazda 323 forums.
Ribbed belt guys may just swap the fd one straight in. I think the tensioning arm may still need a shave.
The rx7 tensioning arm is a screw the bolt for tension type and may also fit.
You can also get aftermarket versions of both rx7 alternators up to 140A.
I also think the rx7 guys use a ford taurus one as a upgrade.
Sorry for the long post. Some pix would have made it shorter.
Any questions, just ask.
I was given a stock 100A one from a mazda FD rx7.
I currently have a carby sohc 16v b6. The b3 will basically be the same. Twin cam B6, Bp ect may be different.
The fd unit has a ribbed belt, you need to swap in your old v belt pulley if running one. I'm guessing ribbed belt guys won't need to swap any thing.
To swap the pulleys, you will need to drill the center out from 15, to 17mm after Using a rattle gun to remove both pulleys.
The pulley type on mine was a 3 piece. Almost like 2 big washers to make the v and a spacer in the back.
I used a mates lathe to drill out all 3 pieces, from 15mm to 17mm.
Put the drilled out pulley on the fd alternator with a rattle gun.
You will need to change out the bottom securing bolt on the new alternator because it enters from the wrong side.
Drive the captured nut on the bottom bracket towards the center of the 2 lugs to drive out the bushing and captured nut. Put the bush back in . You will need a new longer m10 bolt and nut for that becuase the fd one isn't threaded now. I found one with a head that was the right size to fit where the old nut went.
You will need an new m8 nut and bolt for the top of the alternator because it is not threaded.
The stock harness will plug in , but the positive crimp lug will need drilling out from 6mm to 8mm. I will be upgrading mine to 25mm2 welding cable. The negitive has already been done with it last week.
The tensioning arm will need a shave on the bottom to clear the alternator . It will be 2mm or 3mm.
To make it easier Put the belts on all pulleys before bolting it in.
With that wall of text done , a few other thoughts.
A fc rx7 has the v belt already there. It is 80A stock. It may be the same. I don't know the pulley sizes. I compared lug distances from ebay descriptions and posts on mazda 323 forums.
Ribbed belt guys may just swap the fd one straight in. I think the tensioning arm may still need a shave.
The rx7 tensioning arm is a screw the bolt for tension type and may also fit.
You can also get aftermarket versions of both rx7 alternators up to 140A.
I also think the rx7 guys use a ford taurus one as a upgrade.
Sorry for the long post. Some pix would have made it shorter.
Any questions, just ask.