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Re-Rebuilding the 440-493 in a 1970 Charger

I called FBO again.
Dana assured me that a diode was in the package but agreed to send another. Don IS retired but does pop in to help with tech questions that are above Dana’s knowledge level.
I’ll try this and if it works, the system stays. If not, I’ll return to the Mopar Chrome ECU that I had before. I can use this FBO box on another car later if need be.
It has been raining so much here, I haven’t been able to drive the car. These tires are splendid on dry pavement. I did pass through rain when going to Spring Fling last April and the tires did well but I’d rather wait. If/when I leave this state, I may have to adjust my perspective on driving in the rain. Tennessee is one possibility and from reports I have read, they get more rain in July than any other month. For a California guy, that is really weird. In normal times, it can rain between November and May but summer rain is rare.
I'm from SF Bay Area but lived in Alabama for 3 yrs (not far from Tennessee). It rains the most in the summer in the Southern USA, much like the tropics. Very humid with lightning storms and rain drops as big as a house. It usually comes and goes quickly though so it's not raining all day long in the summer usually. To demonstrate how humidity works, I was very surprised to observe my first week there that it rained super hard with inches of rain pooling on some nearby tennis courts and when I went inside for class there was at least a good inch of standing water there. When I got out of class 90 min later, the rain had stopped AND the courts were BONE DRY. If that happened here in California, the rain would take days to dry out. Over in the south I couldn't believe how the humid air could absorb all of that water like a sponge.

KD, I created an FBBO thread a few years ago on how many months out of the year do you drive you mopar? Here in California, most of us could drive them 9-10 months a year if we wanted to due to the temperate climate. Some responders said they can only drive 3 months out of the year due to ice and snow, etc. Man, that is hobby dedication for those mopar owners! We're really spoiled here for driving. I would imagine in Tennessee if you want to avoid rain you could still drive 6-9 + months out of the year, but much of it likely would not be consecutive.
Back when DadsBee/Wayne offered to send me a diode for the tachometer wire, I had the impression that one end of the WIRE had a stripe of paint on it to show which end went toward the coil.
Then the diode from FBO arrived…

The top one is from Wayne.


Neither of these had paint on the wire itself but they both do on the body of the diode. I saw this when I got the one from Wayne but given my inexperience with most things electrical, I must have misunderstood.
Regardless… the tach needle still bounced at idle but not that much once the car was moving.
I’m going to solder in this FBO diode and see if it helps.
I even told you the strip was above the numbers. BTW.. what number is on theirs?? I sent you a 1N4004.
I was going to mention that the cathode is the end with the stripe when you first mentioned Wayne's wasn't marked. All diodes are marked like that. Cathode is negative and the anode is positive. Sorry, I forgot to post that.
Even that terminology is lost on me. It simply isn’t something that I ever had to learn for work or play.
Thanks for the efforts, I just get lost when some terms are not familiar.
I soldered in the diode…



I wired it into the harness and got ready to light it up.


The needle still bounced the same.
The tech guy at Dakota Digital tried to explain to me that their products can pose problems with some ignition systems so….


The MP chrome box is back in, the ballast resistor is in play too, like before.
The tachometer reads normal again.
Sometimes we try “upgrades” and they just don’t work.
Back in the late 70's when I put the MSD 6C box on my Duster, the tach bounced too. It got cured by the separate tach adaptor box they made. Different scenario between you and I for sure but maybe there is a fix out there.
Well, I'm not changing out the gauge cluster. The easy fix was to just go back to the Mopar Performance ignition system. I don't have a rev limiter with it but the engine isn't so wild that I lose my mind driving it.
As time goes on and issues keep popping up, maybe Dakota will come up with a fix. The unit from MSD chilled out the signal to the tach due to the multiple strikes the ignition box was designed for. Until then, you have it fixed.
Well butter my butt and call me a biscuit. I'm surprised, and bummed for you that it isn't working out.
Maybe the box will be good for the jigsaw Charger!
Dana at FBO said the diode helps with the factory Tic toc Tach but didn’t know about these Dakota Digital units.
Jigsaw has a factory appearing tach from Charger Specialties…. One that I bought in 2001 and had in Ginger until 2015.
Regarding the brakes:
I have noticed that with the vacuum pump providing all the assist for the brake booster, I sometimes outpace the pump if I am doing repeated hard braking. Stop and go traffic does not pose a problem but when I was "bedding in" the rotors and pads, the pedal feel was starting to resemble that of a power brake car with the engine off.....a few decent pumps but then a hard pedal with poor reaction.
I figured that I was using up more vacuum than the pump could provide.
I really wish that the hydroboost would have worked. I still suspect that the unit I tried had some defect in it. I'm sticking with this vacuum pump but will consider trying a different hydroboost setup sometime in the future.
I added an inline vacuum tank to supplement the system.

The way it is plumbed in those pictures turned out to be backwards!
I had to exchange the hoses on the tank . The vacuum pump needed to draw negative pressure (vacuum) through the check valve on the tank.
As it is now, the pump has to run a moment to build vacuum before the brakes are assisted. Once it does, it seems like it will be fine.
Another thing.....Oil leaks.
It has always annoyed me how I've always had trouble with leaks. I've tried different gaskets, sealants, hardware....still I have had leaks somewhere.
At the risk of a J I N X, I don't see any.
What the heck did I do right this time?
First up, I think that remembering to install that simple oil slinger kept oil away from the front seal in the timing cover. I've had leaks from there in the past. Secondly, I used those black stiff oil pan gaskets and this.....

566 R.JPG

The oil pan is dry, the timing cover too. NO drips off of the valve covers. I used to get this:


I could have the underside clean and within 20 miles, I'd have a few streaks on the right header. I suspected that the front seal leaked and with the fan and regular airflow, oil would travel along the oil pan rail and then over to the header.
Here is a picture after a 50 mile drive the other day:

618 V.jpg
618 W.jpg

I was really surprised!
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Along with the sealer, parts being dry etc, you didn't immediately start the engine. I've always had the best luck with at least letting sealer setup overnight before putting fluids back in.
That is partly true. I did have that rear main seal leak after I first got it started. I may have let it sit overnight after putting the pan back on.
I checked the pump last night. It is pulling 22” of vacuum. The engine pulls about 7-7.5”.
I’m not sure which side of the tank gets the check valve. I’m guessing the side leading to the booster since the booster has a check valve on it. I should replace both. The one on the booster is surely 1975 vintage.
KD - man, you've got a lot of different repair topics in this thread! It took me a minute to find your last post on your brakes. I've also had some dissatisfaction with my brakes (Power Front disc, rear drum) and have done some tweaking and checking and research the past few years. I just came across an older FBBO thread that may give some additional things we both can check. Read through on this and let us know your thoughts - could there be something here that one or both of us have overlooked?
Anybody using a 15/16" bore master cylinder
Another weight savings idea….


This is a space saver spare from a late model Charger. It has never been on the ground.


For those that will say that the bolt pattern is wrong, I test fitted it. The center register fits and the lug pattern is so close, I don’t see it could be a problem for a low speed, temporary spare.


I will need a set of these lug nuts, found on many Fords. They are 1/2” x 20 but have a wider seat.


There is a nice weight reduction.


38 lbs … next is the 225-75-15 on a 15 x6 1/2.


There is a 21 lb difference.
KD - man, you've got a lot of different repair topics in this thread! It took me a minute to find your last post on your brakes.
Anybody using a 15/16" bore master cylinder
I was thinking the same thing. All good stuff. I was addicted to the hydroboost part of this until it went south. Then I was checking in from time to time to see how the brake story ended. Not sure that we have a happy ending yet. Mr. Dog, have you come to a place with the brakes where you are completely happy? Very curious because I have the hydroboost system that was on the 440 motorhome I tore apart for the overdrive not long ago (so I have a pump that was bolted to a 440 and working). I am also getting ready to order discs for the front of my 68 Coronet (power drums car). No cam specs yet but am thinking of going with the Hughes whiplash, in the motorhome 440, until I can rebuild my "original" 440. Not sure if that cam would cause vacuum issues.
The brakes seem to be the best that they have ever been. As odd as it will sound, I must be chasing an impossible result. No combination that I have tried has matched the feel and performance of a solid A body manual disc-drum setup. The weight of this car may be to blame. I'm around 3900 lbs so I'm a good 500 lbs heavier than my 67 Dart that stops excellent.
I haven't driven the car much since I added the vacuum tank to the system. Prior to that, it stopped great but the pedal got hard after repeated braking...as if the volume of vacuum wasn't keeping pace with the demand.
Theoretically, the tank should help. Without it, the brakes were great as long as I wasn't doing repeated stops.
I wish that I could pin down one specific change that made the greatest difference. In reality, it was a bunch of small steps.
The swap to the bigger front brakes, the pedal leverage, the rear brake pads, bedding in the pads, the vacuum pump and finally the tank all incrementally improved matters.
The hydroboost should have worked. It remains a mystery as to why it did not. I still have it here in a box, ready to return it. I feel a bit "burned" by the efforts that didn't pan out to the point where I wouldn't try to install it in this car again. I would try it in another car....Jigsaw is a manual disc-drum car though and it stops quite well as it is.
Is Jigsaw's brake system all stock stuff? How would you say it compares to the Ginger's current setup?
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