Interesting information from Stovebolt re: Timing. True?

[MustangSix]

CC, I'm not irritated at you. I'm just sharing your frustration. An engine that pings yet needs massive advance at idle is a tough problem to solve.

Steve, springs don't control the total mech advance, but rather the rate that it's delivered. There are stops that control the total mech advance. By flipping the weight or attaching it to a different hole (depending on distributor model) you get a different total. The distributor weight says 10 to indicate distributor degrees. That's doubled at the crank.

 

[Anonymous]

That is what I was trying to make clear. Good job.

 

[Anonymous]

CC,

Quick question for ya

When you are using the timing light you are (when you check the initial advance) dialing the dial on the timing light back to 0 right??

The reason I'm asking is this statement from you further up,

I have a Craftsman dial-back light that I'm using for this test. I always use the light so that the mark on the balancer is lined up with the TDC mark on the timing chain cover.

If you do this with my advance light, (when checking base timing at idle) the only way you can make the 2 line up (mark on the balancer and mark on the timing cover at TDC) would be to move the knob on the light so it would read 15 degrees advanced (in your case) on the timing light itself.

Thus you are adding an extra 15 degrees to begin with. Rest of the numbers look fine to me.

Thus 57-15 would actually equal 42 degrees total advance which would be in the ball park

Maybe I'm reading this all wrong though...

Good luck!!

Later,

Doug

 

[Anonymous]

Thanks again guys - here's an update on today's developemetns.

John - Funnily enough, I *do* understand what you're saying. I've been playing with this so much I'm going to be a timing expert by the time this is all done (ha ha!)

Jack - I didn't think you were irritated -- it was LEROY who seemed to be frustrated with me for some reason.

Steve - you are correct. When I found 35* inital to be the "sweet" spot with no VAC, I then *reduced* the dizzy down to 17* and hooked the vac canister up to full manifold vac to achieve 35* intial WITH vac. The thing that scares me here is that I don't know what "ping" sounds like. Now, I've heard it described (rattling, marbles in a can, etc.), but I don't hear anything like that. Now, someone with experience my hear my engine and say AH, PING! but I'm worried since I don't have a frame of reference.

Doug - Since math is hard <chuckle>, I generally set timing so that the balancer mark is at 0 on the timing chain cover, and use the Dial to tell me what the readings are. So for intance, if I want 15* initial, I set the dial to '15' and adjust timing so that the mark lines up with 0. Does that make sence? However, I will check again later to make sure that you are correct and I'm not acutally adding timing by doing it wrong. Boy would I feel dumb!

Now for the update - This whole "set by idle" thing sounds better than it worked. I actually took the car for a spin this morning and it ran like CRAP. :x No power, it was sputtering and surging. An absolute mess. So, either I did someting really wrong or Tom at Stovebolt was wrong in his advice. I went back, set everything up normally (with 15* inital) and the car ran great. Actually, with the new 2bbl setup properly, it ran REALLY great.

So, one mystery is somewhat solved -- the setting timing by idle thing didn't work in practice.

That STILL doesn't explain why my dizzy is giving me a full 57*. Actually, I'm going to tripple-check all the readings with tach hooked up and find out when that RPM is actually coming in.

 

[Anonymous]

OK MORE INFORMATION!!

So, one thing I found out was really wrong -- the aftermarket tach in my car is off by about 300+ RPM's. So, when I though I was idling in drive at about 650 - I was really at almost 900. My Park Idle speed was over 1200. No wonder it was so smooth.

So, using an tune-up tach (and confirming against a timing light I have with a tach), I reset everything down and here are my new readings.

17* initial at 500 RPM (no vac)
36* (mech + advance) all in at 2500 RPM (no vac)
55* (mech + advance + vac) all in at 3000 RPM

Now, I also looked at my cruising advance - about 2200 RPM with everything connected, and I'm running about 46*

So, those are the new numbers. I don't hear anything that sounds like Ping.

So, we still have this 55* number which is somewhat concerning I guess.

The other thing, is that the car runs REALLY crappy now in 'D' - at a true 650 RPM in Drive, the car is pulling about 7hg of vacuum. It shuttering and really just being angry. Now I need to figure out how to fix this...

 

[Anonymous]

Hi, CC;

Glad you found the screwy tach - I wondered about that because of what happened to me when I re-did my 79 Fairmont rebuild a while back - this all sounds familiar...!

When I put the distributor back in, after I had fully disassembled & rebuilt it, I missed by 1 tooth. When I started up, all seemed fine. I adjusted for my initial 12* (stock cam likes 12-14*) at the lowest stable idle (about 400 RPM). When I went to rev up onto a highway on-ramp later, it "hit the wall" and wouldn't wind past 3000 RPM for nuthin' .

Well, pulled out my pre-teardown photos (that's my version of "memory") and noticed the vac can pointed a little different direction - about 20 degrees worth. Under the timing light, at full advance with vacuum, I was showing 48* - should be too much, I thought. But, backing it down at idle just made the engine stall.

Thinking I'd goofed up the shaft or something on the distrib, I pulled it out and noticed my scribe marks weren't aligned (it was dark out when I first put it in - honest!), so I stuck it back in. It started on a touch and runs perfectly with 14* static, 38* total, winding forever if I let it. It never hits that "wall" now, as hard as I can push it. The vacuum is stopped by the emissions controls after warmup, otherwise it gets more hi-end hillclimbing power when on port vacuum.

The bathtub-shaped chambers in these engines can really hide knock. In a conventional wedge engine (like the 390 FE family) the knock is very noticeable, but not in these. So, I've taken to running up that on-ramp at WOT and readjusting the advance until it keeps winding without that "wall". Now my power, mileage and emissions are all good at once.

Maybe this will help?

 

[Anonymous]

Sorry, I forgot to mention one other thing in my previous post:
The Duraspark distribs can actually trigger off of the FALLING edge of the trigger wheel. This can cause confusion if the thing is 1 tooth off. Study closely the relationship between the RISING and FALLING edges of the star wheel and the high-voltage contacts in the cap. If the teeth are out of synch by 1, the falling edge of the star against the pickup will trigger a spark, which will be delivered thru the NEXT cylinder's contacts in the cap. It's a very short duration spark, but it "looks" under a timing light to be normal, just 10 degrees off! This causes great confusion when installing Duraspark where points were before. Been there - it took an oscilloscope to figure it out! The crazy car ran fine up to 3000 RPM (it was a V8), then stumbled above that, but idled fine and seemed OK otherwise.

 

[BIGREDRASA]

CC, all this brings back echoes of a problem I had with an old 2300 Pinto. The cam drive belt had slipped one cog, and power was down. I could advance the heck out of the ignition timing, and didn't get pinging. I didn't get much power either.
The fact that you have new gear, chain etc, doesn't necessarily guarantee the cam timing is OK. For the heck of it, pull your valve cover off, and record the degrees at which the intake and exhaust valves open and close. You can tell the valves are closed with your finger on the rockers. Once again, it is easier to do this with the plugs out, so you can manually turn the engine. Check the opening and closing against your cam specs. At least you can rule out that variable.

 

[Anonymous]

This distributor thing has me concerned. I pulled the dizzy last night -- and these can be grumpy to get back in. There really only seemed to be a couple of ways that the shaft wanted to seat. I tried to seat it a bit off in either direction, but it never wanted to go in. I was able to get it in a bit to the right, but when I started the car up it sputtered and gave me hell.

 

[Anonymous]

HOLY CRAP MY VACUUM ADVANCE IS ADJUSTABLE?

For gigles I stuck a couple of sized allen wrenches in there and found one that sort of "locked" I started turning a then checked it with the car running and - sure enough - my total advance is way down!

Now, the killer thing is that everyone says to have no more than 36 - 38 deg "all in" - well - that's kind of impossible since I get 35 deg just with my mechanical advance!

Now, I played around adjusting the idle with the distributor again. Since I have a real tach now and can check real engine speeds, I found that 25* advance gave me a really smooth idle at 650 RPM and up to about 10hg of vacuum. MUCH smoother and better than before.

I played with the canister adjustment a little and took it for a spin. In terms of cruising and WOT, it runs about the same as with my previous setttings (which is good). HOWEVER, the engine temp is down, and my idle characteristics are better than before.

I re-checked my timing settings and here's what I found

25* initial
42* at cruise (about 2200 RPM)
50* at 3000 RPM (vac + mechanical)

So, these numbers seem a bit better, eh? All settings are down across the board with higher initial. Again, I still don't hear any pinging so the only change was really to improve the idle A LOT.

Thoughts now?

 

[Falcon62]

I pulled the dizzy last night -- and these can be grumpy to get back in. There really only seemed to be a couple of ways that the shaft wanted to seat. I tried to seat it a bit off in either direction, but it never wanted to go in.

Distributors aren't hard to reinstall - really. What you describe is caused by the oil pump drive shaft, which is run off the base of your distributor, not lining up with the hex socket on the distributor drive. What I usually do is move the distributor a tooth and if it won't go back in, bump the engine to line up the oil pump driveshaft with the drive hex. This is done with the distributor drive gear and the cam gear fully engaged so timing remains accurate.

I suppose you could also try turning the oil pump driveshaft with a 5/16" inch socket on a 1/4" drive, but that would require pulling the distributor back out. If I have it set where I want it, I don't need to pull it back out.

At least with a hex shaft we have more opportunities the first time around, the SBC crowd only get two as the oil pump drive is like a common screwdriver (or at least it used to be).

 

[Anonymous]

:roll: thanks guys! now i don't remember anything i knew about timming...frank...

 

[LEROY POLL]

HELLO CORELLIAN SORRY!!!


I STARTED READING YOUR POSTS AT 3:40 A.M. AND WRITING AT ABOUT 4:00 A.M. I HAD BEEN UP ALL NIGHT. I WAS NOT IRRITATED BUT MORE AT BEING DIRECT, AND MAYBE (RUDE) AND FOR THAT I AM SORRY.

I WAS TRYING TO OPEN YOUR EYES THAT YOU ARE OVER LOOKING SOME THING. YOU SEEMED TO ME TO BE SAYING THERE IS NOTHING WRONG. IF YOU RE-READ MY POST, I BELIEVE YOU WILL SEE THAT I WAS TRYING TO GET YOU TO SEE THEIR IS SOMETHING WRONG.

AGAIN I'M SORRY YOU THOUGH I WAS IRRITATED, AND I'M SORRY IF ANYONE ELSE READ IT THAT WAY. PLEASE FORGIVE ME.

I HAVE READ YOUR OTHER POSTS TODAY AND NOW I SEE WHAT I OVER LOOKED. WHEN YOU SAID YOU COULD HEAR NO PINGING I WAS BELIEVEING YOU WERE ROAD TESTING YOUR CAR EACH TIME. UNDER LOAD YOUR MOTOR WILL NOT BE THE SAME AS WHEN YOU HAVE IT UNDER NO-LOAD.

YOUR VAC. ADVANCE WILL NEVER BE WHAT IT IS THE WAY YOU ARE TESTING. YES YOU CAN RUN A MOTOR AT A VERY HIGH INITIAL WITH NO LOAD. BUT UNDER LOAD YOU VACUUM WILL DROP TO AROUND 10-12 LBS, NOT THE 15-20 LBS YOU CAN GET UNDER NO-LOAD COND. AT WOT YOU GET AS LOW AS 2-3 LBS OF VAC.

YOU SHOULD BE LOOSING ABOUT 8-10* VAC. ADVANCE ON THE ROAD. PUTTING YOU IN THE 40*-42* AREA.

WHEN YOU SAID YOU TOOK THE CAR OUT AND TESTED AND IT WOULD HARDLY RUN YOU WERE FINDING OUT WHAT EVERYONE WAS SAYING. IT WON'T RUN THAT WAY. WE WERE MEANING UNDER LOAD. EVEN THOUGH YOU WERE NOT HEARING THE PINGING OR RATTLING WHEN YOU WERE ON THE ROAD IT WAS HAPPENING.

RUN A VACUUM GAGE INSIDE YOUR CAR THE NEXT TIME YOU ROAD TEST AND SEE HOW FAR OFF THE DIFFERANCE IS ON YOUR VAC. YOU WILL PROBABLY FIND YOU ARE RUNNING MUCH CLOSER TO 36* THAT 56*.

ALSO YOU CAN TEST WITHOUT GOING ON THE ROAD AND MAYBE START HEARING THAT RATTLE. GET SOMEONE TO HELP. HAVE THEM SET ALL BRAKES AND THEN PUT THE CAR IN DRIVE. THEN HAVE THEM RUN THE CAR UP TO 2200 RPM AND YOU WILL SEE WHERE YOUR TIMING IS RUNNING UNDER HEAVY LOAD. THIS WILL BE TESTING LOAD COND. UNDER FIRE!!! THIS IS WHERE YOU WANT VERY LITTLE PINGING.

YOU ALSO SAID WHEN YOU CHECKED THE # 1 WIRE THAT THE POINTER WAS POINTING STRAIGHT DOWN. MY 1983 MOTOR IS MORE AT 4:00 O'CLOCK. YOU MIGHT CHECK WHAT MARKP SAID ABOUT BEING OFF A TOOTH.

YOU CAN GET A TOOL THAT WILL HELP YOU IN GETTING THE DIST. BACK IN. GET A 12" NUTDRIVER 3/8. WITH A FLASH LIGHT LOOK DOWN AND SEE WHERE THE SHAFT IS AND WITH THE N'DRIVE TURN IT BY ABOUT ONE TOOTH, AND TRY AGAIN.

DO YOU HAVE A 250 OR 200 MOTOR?

THIS IS A BETTER GUESS. ( I THINK!)

LIVE IN GRACE

LEROY POLL

MERRY CHRISTMAS EVERYONE IF WE DO SEE EACH OTHER BEFORE THEN!!!

 

[BIGREDRASA]

CC, did you see my post on cam timing? As long as you've checked everything else, might as well verify that is as advertised. If you put a degree wheel on, you can even verify the duration of your cam.

 

[Anonymous]

°°°°°°°°°

Hey Since this all about timing try this----- Hold the Alt key down on your keyboard and type 248 on your numeric keypad and you should get a degree symbol..

°°°°°°°°°

 

[Anonymous]

CC-

1). The Vac advance should be hooked to 'timed' vacuum- the one that comes on just after the throttle plates open. Tey are designed so that when you step on the gas (UNDER LOAD), the vac adv kicks in, adding timing to help fight the increased load. With it hooked to straight vacuum, it does almost the oposite (timing drops away vice increasing). NOT GOOD.

Remember that the #s you're shooting for are UNDER LOAD- not revving the engine in park or neutral- they are dynamicaly different conditions, and require different settings.

2). In any case, you secondaries should NOT be open at idle- your primary blade should be cracked open a bit. If your engine needs the blade open so much that you're having running problems- something is really wrong with your combo. Having the secondaries cracked will ruin the vacuum signal to the primary (RE: idle) circuit.

3). Those #s on your Vette sound high, too!

JEFF

 

[addo]

°°°°°°°°°

Hey Since this all about timing try this----- Hold the Alt key down on your keyboard and type 248 on your numeric keypad and you should get a degree symbol..

°°°°°°°°°

I always use [Alt] 0176; gives ° - yours comes out the same, though.

Now, where's my whip and dictionary?

 

[Anonymous]

Thanks guys.

Leroy - no hard feelings!

Well, this "testing under load" has me curious. In all of my testing, I rev the engine in park up to the desired RPM and check timing. If this isn't giving me accurate readings then man, I don't know how the garage mechanic does this! I may just jack up the rear end of the car, put the car in R and test with wheels spinning! Then I may get some accurate measurements!

Ohchicken - regarding the secondaries open. Tom at Stovebolt told me that the secondary throttle plate has to be open *ever so slightly* - like paper thin, to properly adjust. My primary should be barely open, and the secondary even less than that. If I *close* the secondaries completely, then fuel leaks out of my primary venturis. If I open up the secondaries too much, then fuel will leak of that ventri. So, agian, there is a 'sweet' spot where I can crack the secondaries up JUST A HAIR, and I have no more fuel leaking. Tom mentioned this was a necessary tuning that many people overlook. So, the only way I can get this carb running right is to crack open the seconds.

Can someone do me a favor? Can anyone else with a DS2 conversion on a 200 motor take out a timing light, rev the car up to 3000 RPM in Park, and tell me what readings they get? Or try and match my readings (like intial, inital+mech and initial+mech+vac?)

Thanks!

 

[Anonymous]

I have a DII dizzy in my 200 and I cannot get even close to that reading.

I am running at 12° initial and all in I am at around 39. I have an added 10-15 degrees of mechanical and another 12-17 from the PORTED vacume source I just found three days ago THANKS DAVID.

And I still get a very small ping with this seting. I am looking into carbon buildup and jetting/air mixture as the source now.

I was also dialed in too far advanced at around 15 initial I was getting bad ping at WOT.

It took a long time to get the carb and dizzy to run right with each other, I am still tweaking a few things but things are much more stable now and I finally have power and no ping.

I could not get to 50 total if I wanted to try.....

 

[Anonymous]

CC:
About the "advance under load" business: this can b difficult, at best, to test. The general idea, though, can be seen if you snap the throttle open suddenly while watching the timing with your lite. You'll see it advance until the engine "catches up" to the throttle setting, then it drops back to a non-vacuum state again.

The main difference between using the "manifold" vacuum source (which is high vacuum UNTIL the engine is heavily loaded) and "throttle" vacuum (which is only there when the engine is turning slower than the throttle is requesting) can be thought of as "pulling" performance. For example, consider climbing a steep hill as a sort of long-term load. If you are using MANIFOLD vacuum, the total advance will DECREASE as you try to go harder up the hill (and it will INCREASE if you let up on the throttle). If you are using THROTTLE vacuum, the total advance will INCREASE as you try to pull harder up the hill (and will DECREASE if you let up on the throttle).

During the mid-1970s the use of throttle vacuum became more scarce as emissions are higher during acceleration in that setup and gas mileage tends to be lower in non-hilly driving situations. The use of manifold vacuum spread widely until the catalytic converters came into being, typically during the later 1970s. Manifold vacuum, since it tends to hold the advance at a higher state all the time, tends to improve gas mileage slightly. However, when you hit a hill, the power actually goes down - not always desireable.

Along about 1978 the temperature-controlled vacuum systems appeared. Most of Ford's were the CCSA systems (Cold Start Spark Assist). What these did was to apply full manifold vacuum to the engine while it was cold to improve driveability with the leaned-out emission-friendly carb curves. After warmup, ALL vaccum to the distributor is stopped. If the engine overheats (above 220 degrees) the manifold vacuum is reapplied to advance the timing and cool down the engine (this also raises the idle speed a little to help with cooling).

With careful tuning, the manifold vacuum can be eliminated and the distrib can be connected to throttle vacuum while still meeting emissions. Hill climbing and acceleration is a little better in this mode, but around-town city traffic MPG is lower as a rule.

Here's a tip for checking out that vacuum advance unit: connect it during idle to MANIFOLD vacuum and see where it advances your spark. Then, use that number as your "total vacuum advance" number that will be ADDED to the static+mechanical value when you're climbing a hill or pulling WOT. Adjust it with those allen wrenches until the total is what you're looking for. Most 1960s Fords that I used to tune used 45 degrees for the static+mechanical+full-vacuum advance maximum at sea level. Add 1 degree per thousand feet altitude where you live to this total for a real good starting number. For instance, I live at 6,000 feet in Colorado, where the underhood sticker reads "static timing 10 degrees. Add 5 degrees for 5,000 feet altitude for total static of 15 degrees." This same sticker is in my 1979 Fairmont (200 CID) and my 1979 T-Bird (351W engine).

Hope this helps.