B20a conversion.Alternator problem (carb)

[Civvy]

I've done the B20 swap months ago! The car was originally carbed. It's still carbed and running quite sweet on a modified a20 carb/ modified a18 dizzy.
Now the other problem was the alternator. The wiring harness on the car has a built in regulator and so since the B20 alternator had a built in regulator, it couldnt be used! however, i did manage to custom the job using my a20 alternator by having the B20 alternator pulley bored out to match the a20 alternator shaft! Result...it works. But, the alternator isnt mounted as solid and as professional as i'd like it to be! it's got 2 bolts thru the bottom as aposed to 1 long one and well, they dont fit the bracket and i find my self checking them twice a week or so bcos they have come undone twice before. the adjustment mount at the top is fine.

Actually. I think i might of just thought up the solution!! Have a new bottom braceket made to fit correctly...doh!
Has anyone else come across this issue? am i using the best alternator??

[carotman]

Well, I didn't know that the A20A and B20A alternator shafts were different... interesting!

I guess I should compare it with the 3 spare alternators I got here (hehehe)

I do know that the bottom bracket is different between the B20A and A20A. The best thing I can think of is to use the B20A alternator but install your original alternator hardware in it. I know for sure that the A20A alternator internals can be swapped between the carbed (3 connectors) and EFI (4 connectors). I never thought the B20A and A20A were different (except for the pulley).

Do you have a picture of your original alternator with the cap removed?

[rjudgey]

he's talking about A18/ET alternator from carbed prelude which uses an external voltage regulator the alternator is completley different design to the A20 and B20 ones as well as the wiring. Any ideas? Is their a way of activating the B20 alternator into working? Don't know why he's worrying about he managed to convert the pulley over to the A18 alternator!!

[PhydeauX]

You should be able to rewire it to use the internal regulator of the b20 alternator. I dont have the diagrams in front of me but a little creative wireing should get it working no problem. Sorry for not going into much detail but its almost 2am and I cant think.

andy

[Civvy]

Just remembered..When i did the swap i tried the B20 alternator and it never worked then but, at the time i had a harness issue.. I'll have to try it again!
It even has the same wire codes apart from the extra for F.I.
Thanx rjudgey.. i thought the a20(carbed) and a18 alts were the same mounts!
I'm worried about it because the bottom mount isn't perfect! ..If the Wife's driving it and it comes off the breakdown chaps wont have a clue!
I wish they'd stuck to the 'v' belt tho.. cant beat them!?