dawgtide

What are the thoughts on a MSD ignition and sloenoid plus an Optima Red Top battery for my 1967 289 with Holley 4bbl and bored .030 over and Comp cam? It seems to drain the battery ( 3 yrs old) down with some cold cranks.

Gun Jam

works fine on my 66 with MSD...

Did you drain it dead by leaving the lights on one day?
What was the longest it sat for between a decent drive?
How long has it been doing this?
Do you think its charging when the car is running?
are you getting 14v to the battery at 1200+ RPM?

-Gun

dawgtide

Car was shipped to me recently and I think they left the key in the "on" accesory position the entire 5 days of the trip. Battery is charging but not at 14v , maybe 11 or 12v. battery is an autolite three years old.

Any hiccups or tricks I need to know about installing MSD on the car. Is there room next to the battery where the original is located?

Gun Jam

11v is not charging 12v is not charging enough (you must check with engine running at 1200+ rpm) 13v would be close to acceptable 13.5 is okay

if the key was left on for 5 days and the battery was truly at 0v nominal then its a safe bet that its ruined...dusty roads buddy. (who knows how long it was dead before they shipped it)

I would swap a battery from another car and use your volt meter to make sure that the new battery you swapped in is getting 13V or better at 1000+ RPM.

If you put the new battery in and at 1000+ rpm you get 13v or more then buy a new battery for the mustang and go about your business.

If you put the new battery in and at 1000+ rpm you get 12v or less then hang onto the optima battery and troubleshoot the charging system.

There is nothing special about installing MSD I did it once in a parking lot when my box died after 8 years of service.


PS: Check voltage before starting the car it should read between 11.8 and 12.3. When you start the car and slightly rev it up the voltage reading should be higher (13 to 14) if its lower troubleshoot charging circuit.

dawgtide

Thanks for all of the information. It is a great help. I will check with a different battery first. However, I may go ahead and install the MSD. I would rather have that system vs being stranded somewhere with a very old part failure.

JMD

I am NOT a fan of Optima batteries anymore, premium price for what might be a three year battery doesn't make it for me...

I have started using Odyssey batteries for stuff that warrants a "high end" battery.

Gun Jam

humm those looks cool looks like the tolerate 80% discharge too

Starfury

Most people kill Optimas by draining them out, letting them sit and sulfate, then trying to charge them too quickly. The fast charge boils the electrolyte which can't be replaced. If drained out, they need to be charged at no more than 2A, preferably 0.25-1A, and preferably with a computerized charger designed for use with AGM batteries.

Gun Jam

Mine has been good to me but I never let it sit and never let it get too dead.. although I do use the car as a sound system for the garage but I always try to shut it off before voltage gets below a point that would be insufficient to start the car.