timing retard for starting

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joshua dewitt

joshua dewitt

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does the orange box have a factory timing retard for engine cranking/staring only at all?
or have any of you installed come components with the box to control this? my msd 6tn box was in the car will not work unless hooked up like was in the race car. or should I look into another but 6al unit later in life? I or does the fbo control box make a difference, I would like to use my c/d coil and not a ballace resisted round coil... all ready mounted and braced for isolation into car.
also can I use my c/d coil. full 12volts without resistor on a m/p orange box, or will it fry too? requires voltage drop on coil.... with canister style
 
The only retard in any box would be if it's designed into the box, specifically. So "no" Mopar ignition does not do that

Otherwise, you have to devise a way to trigger it differently. Switched ual pickups or whatever.
 
Interesting question..... just a wild idea here.... If the normal triggering from the Mopar system triggers off of the leading edge of the reluctor pulse (which I think I does but would need to be doublechecked), then you could rig up a DPDT relay with the reluctor leads going through it. Wire the leads so that the relay is activated while starting and flips the reluctor polarity so that it fires off of the trailing edge of the reluctor pulse during starting. I have no idea if that would retard it too much.
 
What worked on the stock car was a normally closed momentary contact switch. We'd push the switch/get it cranking THEN release the button. Before that it was balky when hot/wouldn't crank fast enough to start.
 
nm9stheham said:
Interesting question..... just a wild idea here.... If the normal triggering from the Mopar system triggers off of the leading edge of the reluctor pulse (which I think I does but would need to be doublechecked), then you could rig up a DPDT relay with the reluctor leads going through it. Wire the leads so that the relay is activated while starting and flips the reluctor polarity so that it fires off of the trailing edge of the reluctor pulse during starting. I have no idea if that would retard it too much.
Click to expand...

Bad idea. Imagine flipping (inverting) the signal, the reluctor then interface triggers between teeth. That is about 45 degrees, but with uncertainty because there in not a defined edge where the flux changes quickly. The VR interface requires the signal to go negative, then triggers at a threshold going positive. The tooth edge you are thinking about would only happen with reverse rotation.
 
The orange box is known for a timing retard, but at high RPM instead of for starting.
 
KitCarlson said:
Bad idea. Imagine flipping (inverting) the signal, the reluctor then interface triggers between teeth. That is about 45 degrees, but with uncertainty because there in not a defined edge where the flux changes quickly. The VR interface requires the signal to go negative, then triggers at a threshold going positive. The tooth edge you are thinking about would only happen with reverse rotation.
Click to expand...
Thanks, and I thought yo might chime in. It all depends on how narrow the pulse is; I figure it the pulse is about as narrow as the tooth on the wheel, not 45 degrees wide. So I figured was pretty narrow but could well be wrong. Well, most wild ideas don't work out....
 
RustyRatRod said:
The orange box is known for a timing retard, but at high RPM instead of for starting.
Click to expand...
Agreed & it is a malfunction as opposed to a designed function. I would highly suggest not purchasing an orange box tho I hear the real old ones were OK for not going belly up (another orange box issue) but likely had/did the same retard error
 
I plugged in a reverse polarity pick-up, one time. It had different color-coded leads on it.I paid it no attention. I ball-parked the initial,fired it up, and finalized the idle timing with the light. Great I thought;back in action. So I wanted to check the all-in power-timing. Oh-oh, no can do. The engine started all kinds of shennanigans, from popping, farting, and running like ,well, you know what. It started this almost as soon as the Rs went up and just got worse. So since the light was still connected, I pulled the trigger. What I saw, I had never seen before, and it only took a msec to figure it out. The light was cutting in and out as the timing was jumping all over the place. Ok, so I goofed on the reluctor gap was my next thought. But nope it was right on. I cranked some more gap into it,just to be sure, with no better results.
So then I remembered seeing a little jumper in my stuff-pile, and noticed the colors and ends were the same as the original pick-up. I always wondered where I had got that item. Sure enough it was a polarity inverter! So I plugged it in and hit the key.
Oh-oh, no can do. Now its doing a different dance. So I tugged on the Vcan, and hit it again. Shazzam! I put the light on her and set the powertiming back where it belonged, and continued on my merry way. Later when I got home(this was a roadside repair), I swapped that pick-up for a correctly colored one, and mothballed that odd fellow.
I believe I mighta bin still running the Orange box when this took place. There were all kinds of thoughts running through my head, when the engine died. But I had planned ahead, and spare parts are always in the boot. Apparently the Orange box and the odd-fellow don't make good bedfellows. heehee.
As I've been writing this, I've been trying to remember how far the initial was out with the flipped polarity item. But it's not coming to me. I do remember it was a lot tho.
 
If you all want some start retard in a mechanical distributor, it is done in setting the springs. If there is some mechanical advance at idle speed, none at cranking, that means timing is retarded when cranking. An example: if light spring holds back flyweight at 100 distributor RPM for zero advance, yet advances 6 degrees at idle. There will be 6 degrees retard when cranking engine at 200 RPM. A timing light can be used to measure, when cranking. A simple feel check of rotor is often a good test. The rotor is twisted, and released slowly, should return to stop.

Most set base timing at idle and have no idea how much mechanical advance is in at that point.
 
But having mechanical advance already starting in at idle is a problem for high performance engines..... such advance should not start until well above idle, like at 1200-1400 rpm. NO mechanical advance at idle is the norm, so the answer to how much is in at idle is clear: ZERO). Having the mechanical advance moving around in the below-1000 RPM range can cause the idle speed to hunt up and down, especially with a longer duration cam.
 
If you have an orange box and want a timing retard buy an MSD and kill 6 birds with one stone.

cleaner wiring
Hotter ignition
Multiple spark technology
Delete ballast resistor
Start retard
Rev limiter



I use a digital 6.
 
All y'all except 67-273 are over doing this. Mopar handled it.

The dual pick up distributor handles this task rather efficiently. Hook it up, time it, switch it to flip between start run, you're done. Ehrenberg covered it years ago.
 
KitCarlson said:
Most set base timing at idle and have no idea how much mechanical advance is in at that point.
Click to expand...

And THAT could be used as a startup retard mechanically if done right, because there is some since the weights move a bit before the springs start resisting.

Technically your base timing is where the distributor is physically with whatever amount the weights move before the springs stop them.

The problem to solve is that the weights are still at the end of that free travel when starting instead of returning all the way back to the stops, so solve that and there is your startup retard (some anyway)
 
nm9stheham said:
But having mechanical advance already starting in at idle is a problem for high performance engines..... such advance should not start until well above idle, like at 1200-1400 rpm. NO mechanical advance at idle is the norm, so the answer to how much is in at idle is clear: ZERO). Having the mechanical advance moving around in the below-1000 RPM range can cause the idle speed to hunt up and down, especially with a longer duration cam.
Click to expand...

This is exactly right.
Do you want your hotrod to sound really HOT at idle? Well it will have to idle at an exact stable unwavering rumpity, rumpity, rumpity...
When it starts hunting it reflects poorly on the tuner.
 
We had one years ago that was a 13.5:1 race only engine. All we did was run the ignition hot through a toggle switch. That way, we could simply switch it off, spin the engine with no spark and get it spinnin good then flip the toggle to on. BAM it would light off every time. In fact, my friend still has the car. We are talkin about gettin it outta mothballs and maybe gettin it goin again.
 
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