ymeski56

My 87' 302 can manualy alter the base timing by deshunting a wire spout connection makeing the timing mod and reshunting. What other F-series engines share the ability? Has in been eliminated ? How do engines w/o the method available to them make there base timing adjustments?

transmaster

I am sorry I really don't know what spout, deshunting, or reshunting is

Just call me Sean

iTrader: (1)

Your '87 can't do that. Removing the spout keeps the computer from altering the base timing so you can set the base timing. Just like pulling the vacuum hose from the vacuum advance. All fuel injected engines have this spout connector up until at least '95. After that I'm not sure, I'm not too familiar with the OBDII systems.

Good old Bill

Hey trans, this is a slamm, so I hope its appreciated. Back in the days of magneto ignitions we set timing at 20 degrees or 25 degrees, what ever! We used impulse couplings to retard the spark for starting. Remember? Then came 6 and 12 volt systems, base timing and some sort of spark advance, mechanical, vaccuum or both. Am I on tract at this point? Then came the engineers who felt life was too simple and concockted this crap we are dealing with today. First was the spout connector, which is a jumper to connect to the computor, the terminology of shunt, or deshunt, or reshunt is incorrect to our vocabulary. A shunt is parellel to the circuit not in series to it as is the spout connector. OK, I have rambled on long enough, I hope you appreciate a reminder of history, am not sure about the member and his "deshunting". Maybe I need to look onward through the fog myself.

transmaster

Thanks Bill. I had forgotten about the magneto thing. I once had a old R60/2 BMW motorcycle with a magneto ignition, I must say I rather liked it, and I know all about shunts for metering I work with old vacuum tube transmitters and you do not want to have 2400 volts zoom across a meter it doesn't just smoke, it turns into plasma.

ymeski56

Wasup Sean? What are you refering to that an 87"302 can't do? So, Whats the proper refs: Spout/ Despout? Whatever, as long as it refers to a small gray plug that when secured to its connector, the PCM adjusts timing advances useing base timeing set as its starting point. But when Exspouted, the PCM is disassociated from timing function, allowing manual adjustment change. Then reinspuotreation of spoutee w/ spoutor (Go ahead, make one up, see if it flies! Semantical debauchery for fun or profit) the PCM then controls timing adjustment as before but now useing the new adjusted setting
as timming base. How about this: although I did do some prepping pretty specific to enableing this, component upgrades themselves were minimal. Anyway, I was running at 19 BTDC w/finewire plugs gapped at .o46, 87 Octane, compress/Dry=180-182 psi all cylinders, stock coil, for 2 mos. until it pinged for 5 or so secs. after accelerating mildly up a descent grade,coasting a little at the top, but pinged at 1/2 throttle as I began going down the backside. Although I(200lbs) also had a passenger(180lbs), tools(60lbs), 26 -90 lbs. sacks of cement(2340lbs) shell(100) & pulling a commercial gas cement mixer(?lbs31/2 90/bag cap) I expected ping, just not after it pulled up and over. I anticipated it getting pissed off long before that. This is all true. If I was making it up I would have toned all the #'s down, and entertainment value would be nill. In a mutual forum of anonymity,premised in good will, personally Bull should be employed places better suited like as bar, or save it up for an IRS audit where it could really come in handy. Well enough spouting off by me........Ill get thing rolling

ymeski56

Wow! How did you manage to get that much bull out of 1 F-150 that old, and only 302 ci's??? Rapidfire plugs I'm guessing! Doesn't it say "DO Not Regap!" right on the box?

Just call me Sean

iTrader: (1)

Ok, I'm having trouble understanding what you're trying to say here, but I'll give it a shot.

Your '87 can't alter base timing by deshunting the spout, base timing is what the timing is set at when the spout is deshunted.
No other engines share this ability, because that's not what happens when the spout is deshunted. However, all fuel injected up to '95 share the timing process I described.I don't know if this method has been eliminated because I'm not familiar with OBDII systems.

ymeski56

When the spout plug is removed, at idle, the base timeing (stock/10BTDC) can be adjusted by rotation of distributor. In my case, 18BTDC, is what the PCM then uses as base timeing after spout plug is replaced, when it then controls additional advancement(20-24 additional for my 302). As opposed to when the spout is removed, where timeing & RPM are directly related. Which is why most people don't get past 12BTDC because they start pinging when they step on the accelarator. They seldom realize that their RPM at Idle has increased to 1200+. There is a procedure to mod the timeing to RPM relationship that has to be repeated every 2 additional degrees in advancement. Does that explain better?

Just call me Sean

iTrader: (1)

As I wrote the previous post I could tell that you were saying exactly what I was writing, but the wording was a bit confusing. So I wrote it anyway, just to clarify for anyone else reading it, and now I see the question you were asking. The idle is controlled by the computer and isn't adjustable, and other than the base timing there is no other adjustment you can do. The only other way would be to get a custom programmed computer, which would be expensive.

And 18 degrees BTDC seems like a lot, mine calls for 10.