If i think right on this bracket,it seems to be a "0" and after maybe "5" and then "10"? My timing is just at the end of the bracket above "10" advance with vacum off carb. So maybe about 12... Its a HEI disturbutor with "stocK" springs, should i give the engine more advance timing on idle?

400g engine with 750 edl carb, engine runs nice and good trottle respons,but the sparks is a little dark,just checked the cyl 1 and 2 after engine idle some minutes before i cut it., have adjust the screws on carb a little leaner, but maybe ignition timing need more up?

 

That is the 1965-7 timing pointer, and not sure but looks like the early damper also. The 400 G engine should have the later saw-toothed pointer and thicker damper. They have the marks in a different position relative to the crankshaft keyway.

 

Yes, the factory HEI should be set to around 18-20º initial.

 

Fun71:

Oh, ok i will advance it more then, i just tought it was to much, but maybe not.. I have not test drive the car with the engine yet on road btw. Only on idle and trottle. So.maybe thats the reason the spark plugs are to black?
Just checked two of them earlyer..

Well then i hope the engine will not start to knock/pinging with 18 degrees advance when driving,, thanks.

Run to rund:

Oh i didnt know that, maybe the same type i have on the sb307 then with teeth and numbers, but bigger balancer.

 

If you have both the early damper and the early pointer, your TDC indication is correct. However, the counterbalance is different from 65-7 vs. 68-76 and the crank/pistons/rods/flywheel must be balanced with the damper type you are using.

 

Ok, so if the tdc mark is correct, is it on that "0" mark? It looks like zero #0 and the other one is "10" The middle Point i dont know.. Maybe 5 advance timing after TDC

The engine parts is balanced for this engine setup when it was build some yrs ago.

 

The three marks on the early style timing tab are 0, 5, and 10° BTDC, which corresponded to the timing specifications for the various engines in those years.

- Eric

 

Ok thanks, found a pic on Internet now about it..

Well ok, so lets say i should advance the timing on idle to 18 degrees from my HEI disturbutor, i have an adjustable timing gun, so then i should set the timing gun on 18 degrees so the light will hit the #Tdc "0" if im right?

 

Well... actually... you should set your timing to about 35° BTDC at full mechanical advance, which should occur around 3,000 RPM for most engines.

So, using your timing light and a tachometer,
FIRST check to see at what RPM the timing stops advancing (with the vacuum advance disconnected, of course),
SECOND, if necessary, use an HEI timing curve kit to change springs and adjust your timing so that it does stop at about 3,000 RPM, and then,
THIRD set your timing so that it's about 35° at full advance (at around 3,000 RPM).

At that point, your timing at idle will be about 18-22° BTDC, and wherever that is (so long as it does not make your car hard to crank when starting), is where it needs to be.

You can ask OldsCutlass Eric about this, as he seems to be the designated person for explaining it to people.

- Eric

 

That's how I do it, go for 34-36 at around 2800-3000 rpm and then double check the higher rpms to make sure it doesn't advance any more. Which will give you 18-22 degrees initial. Then I play with the vacuum advance and limit it to 10.

 

Aha i see, Well i Will get a tachometer then first and then try.

 

Its not easy to set total timing to 34-36 advace with only this small piece og metal with 0 to 10 degrees,, but i adjust it about 20 advance on idle.. Try much stuff all the day and didnt get happy...

now i have set the timing to my ear on idle and 2800-3000rpm , adjust the idle mixture screws, took a test drive and didnt hear no pinging, and end up finaly with chocolate colored spark plugs.. done for now....will check the timing tomorrow again.

One of the pipe on the hedman passenger hedder colapsed on some high rpm around 4000, so i need to take it off and weld it...bah... Cheap quality.

 

I dont understand this, should the point on the balancer hit the "0" in 2800-3000rpm when i set the timing light on 34-36 degrees?

or should it show some above over the "10" degrees mark on the metal plate? if so i want to make a new plate and make mesurments every 5 degrees up to 35-40 etc.. Hmm

 

Yes, if you have the timing light set for 34 and the timing is actually 34, the mark on the balancer should be at the 0 mark on the timing tab.

 

Ok thanks, i will try again

 

Timing done, 35 degrees on 2800-3000rpm without vacum
About 20 when idle without vacum, and adjusted to 800rpm idle with vacum connected, engine idle very nice too and the plugs have good color.

Thanks a lot for help.. To the end i understood it..lol
One happy engine and owner.

Will test the car when i have replace the blown out exhaust gasket on passenger side. :S

 

Did you check what your timing runs @3000+ rpm with the vacuum advance connected? It should be around 50.

 

No i didnt, should i set the timing on 50advance on the gun then and hit the zero #0 point there too aswell?

 

Yes, however just reference the setting. The adjustment for this setting will be strictly with the vacuum advance, do not turn the distributor.

 

I would set the advance to near 50, rev the engine, then adjust the advance setting until the mark on the balancer lines up with the 0 on the tab. Then just make note of the timing light advance number (this will be the total amount of advance).

 

I have tested the car today from last timing set, good respons but i can hear some metal noise from about 2300rpm and up when i give some trottle when i driving.

Its not knocking but its very weak wizzle sound or what i should call it, its like i have an loose exhaust clamp, but everything is tight, no noise from idle to high rpm when the car stand still.. Only when driving.. But sounds like it dissapear when i give full throttle on higher rpms...

Im very confused,, tried to set the idle ignition down to 16 from 20, but its still there.... Should i try with lighter weights in the HEI or heavyer?? I hope its not that pinging/knock sympthon

Would i be safe as long i dont give high rpm under load? I fill up 20 liters with gasoline today and add on a bottle with octanbooster but nothing helps...

Have 045" gap on plugs.. And they have nice brown orange color, Could it be to large gap?

 

If you have preignition at mid-throttle that goes away at full throttle, then your vacuum advance is too far advanced.

If you have an adjustable vacuum advance unit, you have to dial it back a bit.

If you have a non-adjustable unit, you can try limiting its range with a stop.

- Eric

 

When i bought the disturbutor it says its adjustable vacuum on it, but dont known where to adjust it or how it works,
is it dangorus to drive it like it is now if it preignition? Is it the same as pinging problem/knocking?

My plan was to drive to car meeting today. About 3 hours drive one way , yesterday i drive the car maybe 10km total without problem.

Or should i retard the timing on disturbutor more to get it more safe when driving? Just tought to fix this fast today.

But if i can adjust the vacuum advance please tell me how see you wrote i can adjust it back a bit... But where? when i got my disturbutor it follow with a little umbraco screwdriver.

 

Aha, maybe you mean this? set in the hex screw and anticlockwise it a bit? How much to you think? 1 turn?

So first i will advance the disturbutor back there it was, then clockwise or counter clockwise the vacum a 1/4 turn? Then check the timing again?

 

If the car pings at part-throttle acceleration, pull over, use Allen key to turn screw 1 turn counter clockwise, reconnect hose, get back in car, drive some more, if it still pings, get out again, turn another turn counterclockwise, drive again, etc.

To check your final adjustment, drive in the left lane of a highway, right next to a concrete barrier, with your window open, at about 50-60mph, so that the sound of the engine bounces off of the barrier and into your window, accelerate progressively, and listen for pinging.

- Eric

 

Hi. Yeah i did this. I have turn it all the way in now to the end and it is still there, but not so much now.. Next step i maybe will install a timing limiter like on the pic. Cause i dont know what else i could do..

 

Exactly. If you are still getting too much vacuum advance, you install a limiter on the vacuum advance lever and start over again.

Note that the limiter shown pushes the lever outward, which advances the timing, so when you install it, ALL of your timing will be advanced to the amount that the cam has set, and you will need to retard the overall timing by that amount by rotating the distributor.

- Eric

 

Limit your vacuum advance so that you total stays around 50.

 

Ok,so after installing a limiter plate the ignition timing need to set up new for every point i place the timing plate? If i understand it right, it will not give so much timing on middle trottles?

, but what if i place the limiter bracket with the back hole instead, so it puch the vacum pin in ,instead? Could it work? Iv got a tip from another to make a spacer to mount in the free hole that u can see behind the timing bracket plate there to push it the pin more in to take away a few timing degrees.

Or, should i just try stronger springs in the weights? Or is that best to use as an last option if nothing else should work?

 

You REALLY need to sit down with a pen and paper, and whatever else you need, and work out in your head how this works before you start changing more things.

It is not too complicated, but it takes a while and once you really get it, it will be much easier.

I am at work, so don't have time to reiterate the details of timing, but there is someone else on here who is an old retired guy, and he has lots of time to give you links and explain things.

Basically, you must keep in mind that you have THREE different things that determine your timing:

1. The built-in stops on the centrifugal advance mechanism and the position of the distributor body, which will set the idle and the high-RPM timing.

2. The weights, springs, and crossbar of the centrifugal advance, which will determine at what RPM your engine reaches maximum advance, and where the advance is in between idle and that point.

3. The vacuum advance, which adds ADDITIONAL advance to the other settings ONLY when the throttle is closed or partly open, and NEVER when the throttle is wide open.

Each of these has be be adjusted / set, in this order, so that it "plays well" with the others, and you should never go to the next one before you have the earlier ones just right, and once they are just right, they should not have to be adjusted again.

By your description (none of us has driven your car), it sounds as though you have too much vacuum advance. That is where you need to be looking now, provided that you set up the centrifugal advance correctly already.

- Eric

 

Heres a good read:
http://www.lbfun.com/warehouse/tech_...ance_Specs.pdf

 

Yeah i need to understand this better, im very confused with this vacum disturbutor, somethimes im thinking to install the msd ignition kit instead, but is have no vacum on it, but sounds more simple. But maybe it not helps, and it will use more fuel without vacum setup.

Thanks for the link oldcutlass,i will try to read it. Somethimes picture description is best learning for my head, but i will read it. And google alittle.

 

Installing the msd is more complicated and defeats your purpose of the vacuum advance for fuel economy.

 

Yeah i guess so.. Want to have best economy with the HEi instead.. Im not sure how it would be if i swap ower the Gm hei disturbutor from the 307 engine either. And what timing it should have from that one.

Well anyway here i found a great guide too.. Here u can see the metal plate is installed behind this pin to make it stop.

 

Huh?
Post 26's pic?
a) that limiter does not push anything, it restricts the pull travel of the vacuum canister.

b) outward would be retarding timing; the canister advances the timing by pulling IN that rod, until it hits that limit plate or the end of its slot.

c) The canister and rotating the distributor to set timing are generally independent things. If you change canisters it may possibly require re-setting the dist'r rotational position to suit, due to slight manufacturing differences in various vacuum canisters.
.----------------------- EDIT ---------------------
Oh, ok
post 34 shows it as Eric describes
post 26 appears to show one incorrectly installed on a loose canister.
Agreed that as per post 34, when the notchy plate is adjsuted, it moves the EXTENDED end of travel of the VA rod, and this alters the timing that occurs w/o any VA. Pretty sure the screw within the canister does the same thing, at least it did on the adjustable canister I bought. Therefore, having both is redundant. The notchy plate is for factory canisters and/or those with a 90 degree bent vacuum nipple, such that an adjuster tool cannot be inserted.
-----------------------------------------------------


I am still not sure on the adjustment of Oldsragger's canister- if CCW limits the travel to a minimum, or CW... but with a vacuum pump to watch it, and any sort of measuring tool, one can readily discern what that adjustment does, and where to set it to attain the desired 10-14 degrees of motion. It's basic math based on how far from the center of rotation [distributor shaft center] the canister's pin resides. Simple triangle. Small discrepancies due to the cosine of the angle, and the vacuum actuating rod moving in an arc, can be ignored.


RunToRund:
"That is the 1965-7 timing pointer, and not sure but looks like the early damper also. The 400 G engine should have the later saw-toothed pointer and thicker damper. They have the marks in a different position relative to the crankshaft keyway. "
====================
Are you sure about that? I thought the position was the same, just the distance from the crank centerline differed due to the three different hub/ balancer OD's. Disregarding the oddball 1964 330's with wrong-side timing marks. It can't possibly hurt to verify that one's TDC mark occurs when the crank is in fact at TDC.

 

Here is the tip i got from one guy here around, i use a coin as a spacer,just installed it now after clockwise the spring in vacum clock to make it easyer to install, should i try this and set the timing on disturbutor again and then try to adjust the vacum clock spring again, or begin with all in from hard spring in vacum clock and out?

 

Not exactly. The adjustment screw should change the spring pressure, and therefore the amount of vacuum needed to achieve a given amount of advance, but NOT the actual range that the lever moves through, which must be done with a limiter at one end or the other.

My post referred to the sawtooth limiter piece that is included in at least one kit (which I thought the OldsRagger had and was using), which limits the range by moving the "zero" point forward a number of degrees; other systems may limit it by limiting the maximum that the lever can get to.



Neat idea.

Yes, that will work. It is exactly the same as the sawtooth piece in the kit, but it has only one adjustment (unless you attack it with a file).
It advances the timing at the minimum or resting point (where the vacuum advance sits when it is not activated, ie: when the throttle is wide open, or when the engine is not running), so it advances ALL timing for the engine, so the timing will need to be retarded slightly by turning the distributor body.

- Eric

 

If you drill the hole off center on the coin you can turn the coin as an adjustable stop. On the spring pressure you want it set so that it pulls all the way at your max engine vacuum.

 

Yeah i will try this out, in the middle time i have order the real one With tooth adjusts,i think it adjust every 5 degrees if i remember right,,, but it takes some weeks to receive.


when i dissasemble it yesterday i study a little more on the vacuum pump and that it moving the timing Wheel inside, so i Learning bit by bit until now i hope..lol

 

Oh, another thing, my sparkplugs looks brown and nice, but my pistons looks brown too.. Is it normal? Or is it because it have ping somethimes when i have drive?

This last weekend i go for a car meet, drive very carefully in uphillroads in first gear and no more than 2000rpm in each gear to not rescue to get the "rattle rockerarm" sound. Most of the roads was flat and i took my time to drive slowely.

But just woundered if its normal the pistons looks brown in there,, one of the pic i just took a flat screw driver to move it away.