Re-Rebuilding the 440-493 in a 1970 Charger

BB BELLA

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are you running a residual valve now? just wondering if a residual valve would conserve on vac. volume required for brake application!
 

Kern Dog

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The vacuum pump is just plumbed directly to the booster. This worked before so it should have worked this time as well. I could put a "T" in the line and run a vacuum gauge inside the car to monitor the system.
 

dodgemahal

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This may not apply to you but I was told to never take things for granted. On a new build/break-in, measure each lobe for taper, and check each lifter for a "crown".
 

Fran Blacker

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If you put a tee have a line that goes to vacuum source on the engine. Put a check valve in that line so under low engine vacuum it's closed. It would help store vacuum. Maybe somebody has tried it? If you run a reservoir tank.
 

Kern Dog

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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.
 

Kern Dog

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The tachometer needle started bouncing after I installed this FBO ignition box.
The remedy is supposed to be an inline diode. Wayne/DadsBee sent me a diode. It is supposed to be wired in one way but the paint had worn off…. So I figured that I would mock it up…
E2FE9813-2862-4B5F-8929-ABFF94771E07.jpeg

I could attach it to the coil on one end and using the screw and nut, attach it to the tach wire.

Well, the first way resulted in a dead tach. No movement. Reversing it allowed the tach to work but the needle still bounced. I’ll probably contact FBO for the piece they use for this problem.
I do appreciate your effort, Wayne. It was worth a try.
Otherwise, the car seems fine.
 
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Kern Dog

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Today I called "Four Seconds Flat"....AKA FBO ignition, credit card in hand. I wanted to order one of their diodes for the tachometer wire.
The woman on the phone REFUSED to take any money.
That is really nice, just like Wayne/DadsBee did. Stamps and envelopes cost money, a person's time is worth something too. It is really nice when people put themselves out to help others.
 

hunt2elk

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Today I called "Four Seconds Flat"....AKA FBO ignition, credit card in hand. I wanted to order one of their diodes for the tachometer wire.
The woman on the phone REFUSED to take any money.
That is really nice, just like Wayne/DadsBee did. Stamps and envelopes cost money, a person's time is worth something too. It is really nice when people put themselves out to help others.
I for one am sure glad someone besides Don is running the show there now. Wonder if he found a buyer for the business? He was getting pretty darn cranky a couple years ago and time to get out imo.
 

dadsbee

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Today I called "Four Seconds Flat"....AKA FBO ignition, credit card in hand. I wanted to order one of their diodes for the tachometer wire.
The woman on the phone REFUSED to take any money.
That is really nice, just like Wayne/DadsBee did. Stamps and envelopes cost money, a person's time is worth something too. It is really nice when people put themselves out to help others.
Well hopefully their diode is magic, as I don't see it being any different than the one I sent you. I'm also baffled as to what the USPS could have possibly put that diode through in their mail system, I've tried to rub the band and numbers off the one I've had on my desk since I sent that to you and I can't even begin to. You sure your eyes aren't going on you like your Mother warned you about.. or colour blind maybe... :poke: :lol:
 

BB BELLA

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easy to test put it on a 9 volt battery and lick the end! if your not awakened turn it around!
 

Kern Dog

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Ha ha. I tried a magnifying glass and two different sets of glasses and still couldn’t see any paint on the wire.
The package came from FBO on Saturday. There was a ziplock bag inside with directions but no diode!
No, I am not losing my mind. I opened the folded paper expecting the diode to be inside but there was nothing. Good think that this is a hobby car and that this isn’t vital to getting the car running. I may just call the gauge cluster company to see what they say. Waynes diode didn’t solve the bouncy needle so maybe another one will have the same result. The only reason that I installed this ignition box was to have a rev limiter.
 

Cranky

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Well hopefully their diode is magic, as I don't see it being any different than the one I sent you. I'm also baffled as to what the USPS could have possibly put that diode through in their mail system, I've tried to rub the band and numbers off the one I've had on my desk since I sent that to you and I can't even begin to. You sure your eyes aren't going on you like your Mother warned you about.. or colour blind maybe... :poke: :lol:
Ha ha. I tried a magnifying glass and two different sets of glasses and still couldn’t see any paint on the wire.
The package came from FBO on Saturday. There was a ziplock bag inside with directions but no diode!
No, I am not losing my mind. I opened the folded paper expecting the diode to be inside but there was nothing. Good think that this is a hobby car and that this isn’t vital to getting the car running. I may just call the gauge cluster company to see what they say. Waynes diode didn’t solve the bouncy needle so maybe another one will have the same result. The only reason that I installed this ignition box was to have a rev limiter.
Wayne, are you saying that he did it until he went blind? Maybe he just went shade blind like I am :lol:
 

Kern Dog

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The man at Dakota Digital said that some ignition systems do cause problems. MSD is one system that can be a pisser due to the multiple spark function
 

padam

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Ha ha. I tried a magnifying glass and two different sets of glasses and still couldn’t see any paint on the wire.
The package came from FBO on Saturday. There was a ziplock bag inside with directions but no diode!
No, I am not losing my mind. I opened the folded paper expecting the diode to be inside but there was nothing. Good think that this is a hobby car and that this isn’t vital to getting the car running. I may just call the gauge cluster company to see what they say. Waynes diode didn’t solve the bouncy needle so maybe another one will have the same result. The only reason that I installed this ignition box was to have a rev limiter.
I’m running an old orange box system

I installed a pertronix rev limiter 2 years ago and have been happy with it. No effect on my tach.
 

BB BELLA

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paint on the wire? am i missing something?
I'm assuming this diode is to stop flyback voltage that could be occuring with some ignition boxes and coil field being broken!the diode should be connected as a tail to ground and not inline. is that right?
 

Kern Dog

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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.

A3C6CE09-F063-4123-9E62-6F80E861A33E.jpeg
 
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