1.
A: your alternator is too low in amperage. OEM Chrysler units came in different amperages (30, 60, 75, etc), or you need a modern hi-amp aftermarket unit. working ok does not mean its the correct one for the cars needs, especially if other things have been added, like hi output ignition, steroeo, aftermarket stuff. It would not be uncommon for the original one to have been swapped out with "whatever mopar one" was handy at some point, even if it was a low output unit or of unknown amp level.

2.
A: IDK, but oem units are 70's tech and no where near modern stuff. Im sure a retro fit is possible - but with your low amp issues above, you need to sort that out first, doing so may help your oem units work much better as well. Dim lights and brightening/dimming with related fluctuations in engine RPM is indicative of low voltage/amperage.

3.
A: Those are combo indicator/running/parking. They should operate anytime the lights are on, and when signal is activated.

4.
A: I strongly suspect this is another result in improper amerage. fix that and your flasher relay will work better (faster) but I would check for the proper relay is installed.

5.
A: They are easy bolt in from under the seat. even universal units "will" fit and function, but check out ebay, craigslist, e-body forums etc for a used set. anything from 1972-74 E-body are the same.

6.
A: 5 psi at idle is way too low. min should be more like double that and climb 10psi per 1000rpm increase up to 40-60psi.
1st confirm that is an accurate reading that you are getting with another, known good gauge. If so, then you have internal clearance issues within the engine, or internal damage. Oil pump has a spring you can change for more pressure, but this will not fix the cause of the low oil press, you need to dig further.
Good luck. Hemi4us

 

Chrysler front side markers are just running lamp / parking light. They do not flash with turn indicators.

I'd suspect that you may have to go through the car and check all the grounding points - bad grounds or excessive resistance will cause a lot of issues. You're dealing with a 44 year old car and what condition the wire harnesses are in, if things were disassembled for painting and when put back together, clean ground mounts weren't prepped for that, etc.

As the previous comment mentioned, is check to see what amperage rating the alternator is.

The flasher units are a plug in small canister (common style in that era). The slow blinking rate might be attributed to low operating voltage or current level is too low.

5 psi is not normal; that's very low I'd expect to see 10-15 psi. If the engine has excess bearing clearances, then oil pressure might be due to that.

Not knowing the mileage or condition of the engine, it would be hard to diagnose.

 

Congratulations on your 74 Challenger. Great car. Post more pictures, please.

First thing I would do is go over ALL of the wiring. Look for bad connections, loose grounds, everything. Many of your electrical problems are probably from bad grounds and wires. Take your time, go over all it it carefully, then check it again. After all of that, then look at the the alternator, etc.

LED bulbs can have direct replacements, like the 1158 (or is it 1157) tail lights, etc. HOWEVER, some bulbs won't allow the turn signal flasher to work correctly. Get the wiring issues fixed first, then look into LED bulbs.

The square lights on the front fenders are markers, not turn signals.

Post more pictures.

 

I'll take a shot at question #1. Believe it or not, that is normal. Mine had the same issue with the stock 60 Amp alternator at idle. I upgraded to a 75 Amp alternator and everything was fine.

 

-Thanks for the replies guys - appreciate it! Next time I'm near the car I'll see what the alternator and check things out for a bad ground
Cheers!

 

I suggest joining... https://www.forebodiesonly.com/forum/widget-pages/home/

It's the main forum for 1970s E-Body Mopars (Barracuda and Challenger).

 

another item to check out - the ammeter wiring (under dash) - this can be a trouble spot. If you see burned / charred wiring (or burnt at the ammeter connections) - you need to address that.

Lot of these old cars went up in smoke due to bad wiring. When cars are manufactured, no one anticipated that these would be around for 50 - 60 years, and wire insulation deteriorates with heat / age / exposure to environmental conditions.

In the pre '75 models, the 12v main runs through the ammeter (if you have the rallye cluster - 4 gauge IP with speedo, tach / clock, water / oil / amps / fuel gauges).

The base IP cluster just has the large speedo to the left of the column and a fuel gauge and warning lights

 

Welcome to the forum! Love the original E-bodies...hope you get it all sorted out. please post more pics of that classic!

 

Be careful with upgrading alternators in old Mopars as full current runs through the bulkhead to the ammeter. Probably the source of most electrical fires in those cars. The ammeter can be easily bypassed. Suggest moparts.com, e-bodies.org, cuda-challenger.com as better forums for the older cars.

 

Thanks for that....excuse my ignorance but what is the ammeters function ..or do you know of a link explaining what it is / how to bypass it??
Thanks again - will also check out the other forums:thup:

 

The firewall bulkhead is notaries for bad connections. Cleaning and replacing any bad wires and terminals will help.