Alternator output

[troublemaker]

Anybody know how high u can go safely on amps. Currently at 45 W/non AC 70 Roadrunner . Would like to get up to 80 or 90 using the same external regulator, 1 wire alternator. I was told wiring could not handle it ( I don't know what that's all about?)

 

[Yatzee]

Anybody know how high u can go safely on amps. Currently at 45 W/non AC 70 Roadrunner . Would like to get up to 80 or 90 using the same external regulator, 1 wire alternator. I was told wiring could not handle it ( I don't know what that's all about?)

Well somebody's blowing smoke up your ***. I have a 130 alternator on my ride but the charge wire goes directly to the battery "+" post with a 125 amp Mega fuse in between. Be it known my alternator is internally regulated and steps up amperage on demand. Say you're running your headlamps (20 amp draw) and you turn on your heater (20 amp draw) that doesn't leave much room amperage wise for brake lights or turn signals so a voltmeter would have a dancing needle every time they were activated.Hence the reason low amperage alternators are mostly a part of the past. This phenomenon clearly indicates there's not enough amperage in the system and you would find the supply voltage is also low. Clearly there's not enough output (amperage-wise)from the alternator to satisfy the demand. Whatever load is at the end of the wire that's what it requires to work properly. If the heater is wired with #14 wire rated at 15 amps and the blower runs with 15 amps max, a 100 amp alternator is not going to send 100 amps to your heater, the regulator won't let it nor any other load such as a fully charged battery. You could hang a 200 amp alt on your ride and the only thing you'll notice right off the bat is the headlights are actually white instead of yellow. Be careful though because the integrity of the wiring and it's connections have to be good - no matter what rating of alternator you use. An engineering rule used back in the day and today is " the load can never exceed the load carrying properties of the wire that supplies it".

 

[mmissile]

We've run 125-200 amp alternators on many cars, without issue. When installing extra accessories, we've always installed a 6-8 circuit, supplemental fuse box.

 

[troublemaker]

Excellent feedback guys. That's exactly what's happening, the load is to great for my alternator resulting in a fallback to my battery. Dim lights etc. The wiring in the car is Mopar and all new harnesses front to back with stock alternator and outside regulator. I'm going to pick up a 80 or 90 amp from summit and hook it up.
Thanks for the help

 

[oldbee]

I'll say that a 80-90A should be fine, but I'll defer to Natchez he'll be on shortly I'm sure. Mine is a stock 40a(?) but I have nothing but heater,lights,(stock) radio.

 

[texas69bee]

Just make sure the wire from your alternator is rated to carry the amps fro your alternator. For your headlights, change them over to a relay circuit.

 

[Ranger16]

For what it's worth, I had a similar situation on my car with the dancing volt meter and dimming lights (with an OEM 35 amp alternator). After replacing the alternator with a 55 amp (had I known what I know now, I'd have gone larger) AND cleaning all the connectors (they where badly corroded and oxidized), I no longer have any such problem. Now I have to admit, that I never use the blower and rarely ever use the wipers.

 

[troublemaker]

Thanx for all the info oldbee, texas69bee and Ranger16. I plan on starting to look for alternators tomorrow. I appreciate all your help.

 

[Yatzee]

Anybody know how high u can go safely on amps. Currently at 45 W/non AC 70 Roadrunner . Would like to get up to 80 or 90 using the same external regulator, 1 wire alternator. I was told wiring could not handle it ( I don't know what that's all about?)

One of the best alternators to hang on a BB is, believe it or not, a Ford 3G (130 amp) that was used Taurus's, Mustangs and Lincolns. They are "clockable".easy mounting with original brackets, come with internal regulator and can be wired with an exciter lead or just "one wire". You can buy either regulator for under $24 and pick one of these alternators at a
auto-recycler for $50. There's a lot of buzz all over the internet including wiring diagrams and they accept just about any pulley type that's made. Their reaction to load draw is stepped and instantanious and if you have a volt gauge they put out a solid 13.5 volts under any condition.
I run an in-tank Aeromotive fuel pump, 17" electric cooling fan, TBI and a pair of twin tranny cooler fans as well as the usual electrical circuits and I've yet to see my volt gauge wiggle with the signals on.

https://www.hemmings.com/magazine/mus/2011/11/Ford-Alternator-Upgrades/3705711.html
and
http://www.qualitypowerauto.com/ite...Output-Alternator-with-Internal-Regulator.htm