What kind of alt to run?

[Allan R]

First, I'm not an electrician or mechanic or this wouldn't be a question.

I'm installing a LOT of power factory options on my 72 Cutlass S. She was born kind of plain. Now I'm dressing her up for the ball.

1. When built she had only the following options PS, PB, AT so it came with a 55 amp alt.
2. I'm adding (power everything) seat, windows, door lock, trunk release, cruise, lighting accessory groups, rear window defogger, headlamp delay, tape deck, rallye gauges, etc. This is going to probably need more than the 55 will handle. I know that Olds put out a 61 or 63 amp for heavily optioned cars. But, will it handle everything?
3. I bought a 1972 accessory junction block and a couple of accessory pigtails to carry the current. Also got the relays.
4. What's the difference between and DX?? and DN plug that goes into the alt? Mine is external voltage reg. I understand that it can be adjusted. probably will need it with this load?
5. I want to keep the car as authentic as possible. Can you get an alt that puts out 100 amps that would fit a 350 L34, and would that be a better way to go?

[BILL DEMMER]

unless the the car was ordered with a heavy duty alternator, air conditioning/heated back glass(rear window defogger-electric grid type),
it would have come with a 37/42 amp alternator.

how far do you want to go with this upgrade?

options:
1) a 63 amp stock type alternator (10dn-externally regulated).
2) an upgraded output 10dn type alternator.
3) an internally regulated 10si alternator(output choices available).
4) an internally regulated 12si alternator(several output choices available and it produces nearly 1/2 of it's rated output at/near idle speed).


are you looking for originality, or functionality regardless, of appearance?


bill

[Bluevista]

I wouldn't think you would need a bigger alternator unless you do have the heated grid window defogger. There really isn't much continuous load except for the defogger.

Allan

[Lady72nRob71]

Hi Allan,

If you are only adding accessories that were available form the factory for your year AND wire them the way the factory did, you should be able to get by with the 63A alt and HD regulator that Olds used. This will keep the car factory looking also.

Some items like the tape player & cruise use very little juice and some like the seat and windows would use a lot but for just a few seconds.

The A/C compressor, blower, and defogger are the biggest hogs.
When Olds installed both A/C and defogger, they wired it so the high speed blower was disabled when the defogger was switched on.
If you hook it up like they did, you should be fine.

Now if you are adding driving lights, big stereo amps, etc, the alt and reg will need to be stepped up.

[ijasond]

I would make the swap to the 10 or 12 si. ditch that voltage regulator.
I use 140 amp 12si from summit to charge my deep cycle batteries for high amp stereo equipment & air ride(probably not necessary with your tape deck. Do they still make tapes?) Better to have a little extra power than to need a little more. I've seen quite a few 63 amp alternators go to an early grave from being overworked.

[joe_padavano]

I agree. I'd go with the 12si of whatever amperage you want. If stock appearance is important, run a fake voltage regulator on the firewall. Only the most anal among us will notice the difference in the connector plugged into the alternator.

[BILL DEMMER]

bear in mind the 10si and 12si have a vastly different appearance.


bill

[Allan R]

OOOHHHKaaayy???
What is the difference between 10si and 12si ( in simple terms)? I know that 1972 was a transition year with Olds alternators, but I have no idea what it was or what to look for.

Rob, Ya nailed it right on. My car doesn't have and wont' have AC, but will have the electric rear window defog and the only time it's ever going to be on is just to show that it's hooked up. Power seat? I know it's stupid, because once you've lost the urge to play with them they stay in the same place all the time (experience). Lots of other power options, but they're not going to be running at the same time. I was asking because I haven't seen many 72 Olds Cutlasses that will have the "high option" list I'm putting on mine. Don't want to have catastrophic electrical failure.

Hey there ijasond: Don't think they still make tapes. But I have some original Olds 8 track tapes that will be used with the player on show nites. Believe it or not, I also have the recording equipment to make my own 8 tracks, and I've got a good supply of blanks. (wow, that feels like I just went through a time warp)

Bill, this car actually did come with a 55 amp alt and wasn't a special order. Anyone know what the A52 build code was for A Body in 1972? Maybe to withstand the cold weather up here with the defrost and lights on a lot???

No plans to pimp this ride. Going to stay as original as possible.

Joe, that's a neat idea. And like you said who would notice??

Ok, back to you guys. Start with educating me on the 10si, 12si or 10dn thing. (please)

[BILL DEMMER]

allan,
if your car came with heated back glass(rear window defogger-electric grid type), it would've been equipped with the 55 amp delcotron.

since you already have the 10dn-you know what that looks like.
here is a truckload of info. on the 10si and 12si.
http://oljeep.com/gw/alt/edge_Alternator_Theory.html

acdelco also makes a solid-state replacement regulator for the 10dn. just put your old regulator cover on in place of the one that comes with the new regulator and nobody will be the wiser-besides you.

if you don't need the enhanced output of the 12si, leave the 10dn in. but, do the solid-state regulator upgrade-it only enhances reliability.

my personal opinion is to go for the 12si-but i prefer function vs. form. that's what i did with ernie(94 amp 12si).


bill