upgrade alternator or battery?

[350Rocket 10+ year member]

Hope you guys can give me your experience/advice on this. I have a 1984 Cutlass Supreme with the stock alternator (78A I think) and I'm pretty sure I'm going to have to upgrade either the battery or alternator this summer, but can't afford to do both. After I installed the dual electric cooling fans I noticed at idle with the fans, headlights, radio and A/C all on the gauge would drop down to about 12V. I'm sure after I install my new components and put the sub back in it's going to be much worse this year.

I can spare enough money to either upgrade the stock alternator or the battery. I have 4 old vehicles right now and almost every one has a smallish AC Delco battery that's several years old. I haven't bought a new battery ever, always ended up buying cheap cars that had a good working battery in them. Since my old cars don't have fuel injection, a computer or electric fuel pump, they put less draw on the battery when being started, so I've had good luck with old batteries. That being said I won't need as much battery/alternator as the typical newer car with the same type of stereo (just PG RSD65C comps and a pair of 4x10's running off an older Sony ES Mobile amp 250W RMS I think, and a 1 12" running off 360W IIRC?

So do you think I'd be better off spending my money on one of those Red Top Optima batteries? or upgrading the alternator? Assume both will cost around the same. Thanks.

Mike

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[Enellz 10+ year member]

With what your running a big battery up front and you should be good. No need for the alternator your not running enough to need a new one.

 

[Crownvicon28s 10+ year member]

I would upgrade the alt. If you upgrade batteries and the alt cant keep up its going to kill the battery anyway. Upgrade the alt and do big 3 and save for a new battery or two depending on power draw. IDK if a 75amp alt is going to be enough for much of a system. How much power r u going to be running?

 

[350Rocket 10+ year member]

I'm powering either a 10" or 12" MTX (not sure which one yet, have both) with a 380W RMS bridged @4ohms and the PG RSD65C and my Kenwood 4x10's with a Sony ES 2 channel amp thats rated 75wx2 RMS at 4ohm in high voltage mode. I don't know that much about this stuff yet but this amp has a high current mode where it will do 0.5 Ohms, but I assume I'm to run it in high voltage mode since high current only does 37.5x2 @4ohms?

The car has non stock electric cooling fans, and I always drive with headlights on and blower fan on for fresh air. Without any amps hooked up my voltage was dropping to 12 at idle in the summer. The battery is an old sh*tty looking Die Hard that hasn't failed me yet even leaving the car sitting in the cold for almost 2 months with the battery still hooked up.

I was really hoping I could get away with either battery or alternator, also I don't know what the Big 3 is?

 

[350Rocket 10+ year member]

Any more advise?

 

[Mr. Slate 10+ year member]

Alternator.

 

[TurdFergueson2 5,000+ posts]

Hope you guys can give me your experience/advice on this. I have a 1984 Cutlass Supreme with the stock alternator (78A I think) and I'm pretty sure I'm going to have to upgrade either the battery or alternator this summer, but can't afford to do both. After I installed the dual electric cooling fans I noticed at idle with the fans, headlights, radio and A/C all on the gauge would drop down to about 12V. I'm sure after I install my new components and put the sub back in it's going to be much worse this year.
I can spare enough money to either upgrade the stock alternator or the battery. I have 4 old vehicles right now and almost every one has a smallish AC Delco battery that's several years old. I haven't bought a new battery ever, always ended up buying cheap cars that had a good working battery in them. Since my old cars don't have fuel injection, a computer or electric fuel pump, they put less draw on the battery when being started, so I've had good luck with old batteries. That being said I won't need as much battery/alternator as the typical newer car with the same type of stereo (just PG RSD65C comps and a pair of 4x10's running off an older Sony ES Mobile amp 250W RMS I think, and a 1 12" running off 360W IIRC?

So do you think I'd be better off spending my money on one of those Red Top Optima batteries? or upgrading the alternator? Assume both will cost around the same. Thanks.

Mike

You saying that you can have enough money by the summer to do them both?

 

[wishbone 10+ year member]

Hope you guys can give me your experience/advice on this. I have a 1984 Cutlass Supreme with the stock alternator (78A I think) and I'm pretty sure I'm going to have to upgrade either the battery or alternator this summer, but can't afford to do both. After I installed the dual electric cooling fans I noticed at idle with the fans, headlights, radio and A/C all on the gauge would drop down to about 12V. I'm sure after I install my new components and put the sub back in it's going to be much worse this year.
I can spare enough money to either upgrade the stock alternator or the battery. I have 4 old vehicles right now and almost every one has a smallish AC Delco battery that's several years old. I haven't bought a new battery ever, always ended up buying cheap cars that had a good working battery in them. Since my old cars don't have fuel injection, a computer or electric fuel pump, they put less draw on the battery when being started, so I've had good luck with old batteries. That being said I won't need as much battery/alternator as the typical newer car with the same type of stereo (just PG RSD65C comps and a pair of 4x10's running off an older Sony ES Mobile amp 250W RMS I think, and a 1 12" running off 360W IIRC?

So do you think I'd be better off spending my money on one of those Red Top Optima batteries? or upgrading the alternator? Assume both will cost around the same. Thanks.

Mike

I believe you should try installing a capacitor if you haven't already. Go to crutchfield to get all the info. you need on them. I will be investing in one the minute I install a second amp and my face off Alpine radio. Yea the radio is old school but why waste money.

WB

 

[TurdFergueson2 5,000+ posts]

I have an 85 Monte Carlo. I am interested as to how you are gonna put your speakers on the doors. Or if you did, I'd like to see.

 

[Crownvicon28s 10+ year member]

Do you plan on upgrading your system? How much money are you looking to spend?

 

[TurdFergueson2 5,000+ posts]

I believe you should try installing a capacitor if you haven't already. Go to crutchfield to get all the info. you need on them. I will be investing in one the minute I install a second amp and my face off Alpine radio. Yea the radio is old school but why waste money.
WB

Yeah I heard that caps work wonders. I plan on getting a 100 farad real soon.

 

[jdawg 5,000+ posts]

Im gonna say like most old G's that I have had and my friends have now, you need to redo all your charging system wiring. I would do it in 1/0 so its safe for upgraded stereo in the future. They never beleive me, just keep buying new alternators and batteries. Then for $30 or so worth of wire everything runs better than it ever had.

 

[350Rocket 10+ year member]

I finally figured out what I have to do with the electrical (the Big 3), already ordered 1/0. I think that will probably keep me from having any charging or battery problems at the wattage I'll be running. I've ordered kick panels for the speakers if OBBN Motorworks ever ships them, if not I'm going to have to do more research into mounting the speakers in the doors, I'm not looking forward to that. I'm not going to buy a cap.

 

[SatterBoi 10+ year member]

I have a 86' with a PGrsd1200.1 and 3 15" Ma Audio subs in it and all i did was use the stock alt with a bigger rv battery up front and a blue top in the trunk, the big 3 done and one run of 1/0 awg and i do fine.

 

[audiolife 5,000+ posts]

I have an 85 Monte Carlo. I am interested as to how you are gonna put your speakers on the doors. Or if you did, I'd like to see.

Kick panel car if there ever was one:.

one under 600 watts a battery...and a high enough amper alt is not as expensive as you think...should be able to get one for under 200 if and when the time comes