Timing question

[fixkick]

what works , is only based on what's there.
CR?
and tuning any distributor with wrong parts, is never easy.
on most vacuum systems, it is independent of the mech, advance system. (always a good thing)
and the vacuum plate moves, to advance the VR sensor timing, one only needs to put stops there. limiting total Vacuum advance.
how ever the vacuum working against the spring inside the vac advance servo there is no changing that. must buy a real servo. or G16./

I will help all I can,, ive helped make changes here on many cars.
lots of modifications, due to parts no longer sold, mostly
even vacuum advance, one can modify them cutting them and making them adjustable, and other tricks. all radical, and with a good spare if we mess up.
using stops is the most easy, on the base plate of the VR sensor..

[Swiftdoog]

Update: so far vacuum advance disconnected, dizzy quite advance, still need to disassemble and measure where it is, but for something odd, the engine now starts easier, the power delivery feels more alive, and the engine response improved a bunch.

I wonder if the engine was indeed at 5 degrees. Just to be sure on the math, 5 degrees on the crank pulley equals 2.5 on the cam? since I´m using a protractor to set the static timing.

Since the rotation relation between the two is 2 cranks for every cam rotation, right? that means that 5 degrees would be divided by 2, right?

[fixkick]

you have the vacuum wrong to the Vacuum advance. (there are 2 types, of porting, hard plenum vacuum and ported above TV valve, )

when you start the engine i bet the vacuum advance comes on fact.
correct, cam is 1/2 crank , exactly 2:1 ratio, correct.
5 crank is 2.5cam degrees.

what direction is the rotor spin,? CCW (like our G16b?)
there were 2 vacuum nipples on the G16 vac, advance, does the G13 have 1 or 2,nipples.
and where do they go, your photos show no hose routings.
the 2 nipple system
the inside nipple is retard
the outside nipple is advance side , to prove that use a hand tool, out side nipple pulls rod inward, for advance) above inside nipple pushes other way.
g16b orig.
http://www.fixkick.com/bbs2/Suzuki-bbs/a...hp?aid=494
no photos of G13 vac, adv. pot. if the nipple is on the rear of the vac. advance, then that is for sure an advance nipple.
this outside nipple must not ever be connected to plenum vacuum , if you do , the advance goes to max as soon as engine starts.
that be very wrong,
that the rear nipple does is add advance as you open the TV>

this is what is called, ported TV vacuum at idle it has , zero vacuum.
the old carb is gone i bet, and so we can not examine this feature, close, but it was there.
if you had a real FSM on this car, (book) it have advance data. there, tables. showing the ported vacuum rules,

have you examined the weber for this other vacuum port.
usually its a hard vacuum nipple down low, way below the TV . this is wrong vac.
then at the edge of the TV,
here is a 1 barrel carb,
see the gold TV, and see that tiny hole, this is vacuum advance port.
0v vacuum at idle, then increases as you apply throttle. this port advances the spark.
the location on the original carb perfectly matches a specific vac adv. pot, and its diaphram diameter,

here are 2 examples of how this works (advance, not smog retard feature , now missing)

see this port, this is downside, plenum side.




and this, this left gauge is ported advance, and this TV gated vacuum gives the engine, that surge of power off the line,..... (0 mph , and first right foot actions)
graphic, P = plenum, M = max vac, 0 = zero vac.

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on the web, do not confuse idle fuel ports, for vacuum ports.
that weber has more identification letters, like DGV , DGEV ,DGAV and DGEV, and DGES. (elect, water or manual choke version)
there is a book on each and will show which port is which,
which weber is this? 32/36 is series,(and venturi size)
some have 2 nipples on body, below electric, chock pot.
left is egr, and right is dizzy.
but i always look at the port action with eyes, and blow in to ports to see what they REALLY do.

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keep in mind , i have no e59, FSM , so cant say what suzuki was doing there.
on most engines of this class
but
when you accelerate off the idle, stops...
mech, advance, is pretty dead. (rpm low)
so what happens is carb goes way rich (by design and tune)"enrich mode"
this means you need more advance to burn the richer fuel, if this does not happen , you lose lots of power, off the line.....
then as speed builds, the mech advance kicks in and the VAC drops and the vacuum advance , backs off.

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what i do ?
is i examine that old carb and see how the advance port works.
then on the new carb, make sure its the same, (forget the retard hose)
its that simple but, with the wrong carb and all is lost.

i dont have an xray drawing of the 32/36 carb, this would greatly help, and the manuals so far ive seen , lack this critical facts.(webers)
ill keep looking when you tell me the Dxxx letters.

[Swiftdoog]

the cam is ccw, like a g16b normally do.

The weber I have doesn´t have the egr port, just for dizzy, I checked it using a vacuum gauge, at idle it doesn´t pull vacuum.

I had the "bog off idle" problem with the weber, advancing the timing cure it, but then I decided to install the vacuum advance and the ping came and well, you know the rest of the story. So far no bog or ping, but lots of power.

The vacuum pot I have installed has the routing to the ported port of the carb, so I only have vac adv off idle.

Talking about the mixture and jetting, I did enrich the carb by upping the jetting number, it came stock as Primary 140 Air Correct 170 and Secondary 140 Air Correct 160.

Before all these changes and with the pinging problem I went to Primary 150 Air 160 and Secondary 160 Air 170. It cure it somehow for a while and then it came back as usual. I believe I can go back to the stock jetting for fuel economy, so far I am getting 25mpg, feels like an alright number for a carb.

There is one thing that bothers me. The first time I installed the weber brand new I didn´t have ping, but I had the original vacuum pot which was damaged inside. Later I bought and install the G13 vacuum pot and the pinging came, now I have disconnected the vacuum pot, advance the timing and the engine runs better, I believe is quite advance now but still runs much much better. "By sight" I am far beyond 8 degrees, still have to measure. Could it be that I am measuring wrong?

[fixkick]

more, lots more,,, that nipple on the weber is called the S-port.
and is for vacuum and advance, and is 0 vacuum at idle.
if idle is set wrong,, the S-port will not be at 0 inches HG at idle. and will mess up the vacuum advance.
this is covered deep in to weber tuning...

real photos to post now, internet deep searching,,,,
v1 = S-port. vac, advance.


closer. now.



here is the site for jeeps that use this carb.
http://www.jeepforum.com/forum/f8/weber-...n-1051137/
and all those tricky weber secrets.... (endless)
id run harley CV carb on a 1.6L and make tuning x10 more easy....
more secrets
the terms DGV, DGEV, DGAV:
D is down draft, G is the mounting direction, V is manual choke, EV is electric choke, AV is water choke...

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so at idle
there is no vacuum here.
then when you open throttle, vacuum is active at the S-port.
these goes to the rear nipple on the vac, advance.
and advances, the spark, if the spring in said vacuum pot is too weak, then the advance will be too aggressive. (fixing that, is not easy task using wrong pot)
by pot i mean the vac, advance, servo.
if the vacuum cause to much advance, only added stops the plate that the pot moves, can cure that.

too bad we dont have a real fsm with the advance tables. known.... then we could do tests.
the only tables we have are the old samurai.
ill look that up, see if i can gleen some facts there. on the POT.

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the sammi book , zero vac, advance data, just leak down test. sad.

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that's ok, the EGR port is an option
what matters, is
how does your G13 vacuum hooklup.... it must be correctly connected.
right now, i bet the vacuum line to the vacuum advance is setting at 20 inches vacuum, wrong.
i cant see your lines, so all my answers here are wild guessing..

the S-port will run the vacuum advance, and will be 0 inches of vacuum at idle.
yours is not.
that is why the advance is wrong.

you start the engine and then you set timing, with the vacuum advance connected.
do not. do that.
set the static time with no vacuum line to the distributor, pull it and plug it.
then set timing at idle.
the after timing is at spec. say 5deg. BTDC.
then running connect up the vacuum advance hose, if you see the advance go crazy high
that means you are using the wrong vacuum port on the carb.
or the carb is set up wrong, (idle screw stop set wrong)

the advance must not go to VACUUM advance max, at idle ever.

[Swiftdoog]

Greetings, measured the timing yesterday, and yet again forgot to take pictures hehe.
The new timing is 11º, a hair maybe to 10 but I doubt is 12. What I did noticed is what you said about the slow cranking because the engine wants to go backwards. But, I also think is because of my battery relocation to the back (long time ago the was of battery stealing began so I had to move it to the trunk). If I used a bigger battery (more amps, right now mine has only 500amps), the engine cranks fast and doesn´t go backwards, also starts much faster.

Just to let you know the experiment is working great so far, no rejetting yet, just testing timing.

[fixkick]

yes, static timing must be near 0 (5,8 and 10 are common) BTDC.
beyond that the piston will force the crank backwards, and fight the poor starter. (all bad, that, hard on battery and starter, "torture"

that is why staring at 0 is best. then when an engine starts, advance wakes up.
back in the old days say 1908 (lizzy days) you hand cranked, the engine, and if not hand spark retarded,it breaks your wrist.
or on any real Harley, motor cycle, we had to same , before each kick start, or you fly over the handle bars,,(not fun) so same with starters.
in this car, and most cars, vacuum advance wakes up first. and the flyweights are dead.

Perspective, (a mind set) one does not tune the distributor to match an alien carb (web) we tune only that Weber , to mech stock spark system
to do both takes a long hard work on a dynometer....
see why? ( answer, cant tune any vacuum advance and i bet filing advance weights is not fun, at 5000 rpm, or effective at tip-in , enrich mode.)
Why not change the accelerator pump linkage, first? a stronger squirt.?

the cam is ccw, like a g16b normally do. GOOD

The weber I have doesn´t have the egr port, just for dizzy, I checked it using a vacuum gauge, at idle it doesn´t pull vacuum.(GOOD)
you have the S-PORT as most do.. and is the correct port. (for the vacuum nipple to the REAR of the vacuum advance only)

I had the "bog off idle" problem with the weber, advancing the timing cure it, but then I decided to install the vacuum advance and the ping came and well, you know the rest of the story. So far no bog or ping, but lots of power.? (no ping?)
(if the G13 advances too fast or deep, why is that a surprise? (devils advocate) its the wrong part.
ever seen dizzy curves? Ill post that last so you can see how real books on cars cover this, sadly our SAMurai book does not,(last carb engine here)


The bog off idle is CARB issues, not spark , a weak set accelerator pump, the idle transfer ports setup wrong, or jetting.
Webers are great but also the most difficult to tune due to the many circuits... very very hard.


The vacuum pot I have installed has the routing to the ported port of the carb, so I only have vac adv off idle. (GOOD)

Talking about the mixture and jetting, I did enrich the carb by upping the jetting number, it came stock as Primary 140 Air Correct 170 and Secondary 140 Air Correct 160.

Before all these changes and with the pinging problem I went to Primary 150 Air 160 and Secondary 160 Air 170. It cure it somehow for a while and then it came back as usual.
I believe I can go back to the stock jetting for fuel economy, so far I am getting 25mpg, feels like an alright number for a carb.

There is one thing that bothers me.
The first time I installed the weber brand new I didn´t have ping, but I had the original vacuum pot which was damaged inside.
Later I bought and install the G13 vacuum pot and the pinging came (well its wrong part), now I have disconnected the vacuum pot, advance the timing and the engine runs better, I believe is quite advance now, but still runs much much better. "By sight" I am far beyond 8 degrees, still have to measure. Could it be that I am measuring wrong?

sure , with the front cover missing, easy to buy one? all G16b fit.

the 1.3L engine, is 300cc less displacement, and has weaker vacuum,(less suck) and will have a different vacuum advance device, but the 1.3L still needs strong advance, due to same fuel, same compression ratio. etc....same fuel mix... (AFR)
they make vast numbers of (did) vacuum advance pots, even by cars body weight.( and 10x more for smog)
if the diaphram on the G13 = G16 sizes then i bet the spring inside, is weaker, matching weak engine....
how to make a weak spring work right, and not over advance the G16, is a hard topic....

the vacuum advance is not optional,, unless you want weak off the line power and wasted fuel each time,
the stock engine setup runs rich fuel off the line (called tip-in, enrich mode) and runs strong vacuum advance to burn all that extra fuel and make huge power.
if the vacuum advance is defeated the stock carb would be rich, and would just not bet burnt, be wasted,
see how the AFR and Advance work , as a team?
race cars (in the day) would remove the vac, advance, and then run very aggressive, mech, advance, (they never idle or tip-in so its not needed, vac-pot-advance)
they run weaker fly weight springs, and get early mech, advance,,


for fun look at this, this is what Toyota (H3LL) did to make advance work like EFI. (joking 1'/2 way) be happy this is not your car.


btw: the EPA now admits they caused more smog than cured, do to this fact. above. (insane idea)




My guess, you are running that cam belt naked and no stock front 16v cover shield.
if true , now no timing marks, and if gravel gits up there or even sand it eats that cogs up to death, very bad,

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last graphic, will be how real books show all this, and lets the mechanic see what is correct and if not correct why it is not correct.
wrong parts, stuck parts. vacuum leaks, etc.
the curve is DUAL.
because its a dual system. one if or low end power, and other is for 5000 rpm power.
and from idle to 5000 rpm. correct .

its really 3 curves
1 vacu
2: mech
3: combined total advance. see?
but the best curves show all 3.
here is a jeep (there are 1000s to look at online, not one on G16, the rare car)

study this carefully
see that blue line this is RPM advance only, not every vacuum or engine load or car body weight. (nor hills) only RPM
now the pink this is total advance,
if you subtract blue from pink you see vacuum advance, performance and you can see its NON TRIVAL.
if you plotted HP or torque , and Vacuum advance, you'd see they are same. (near)
and if your G13 goes too high advance, sure it will ping. and 2x that if lean.
as you can see, having a book on your cars engine, is best, a book with this data. either as a table of data. or the nice curves below. (tops)


early jeep , last carb in USA, is 1994 Isuzu

[fixkick]

see that linear , blue line (ramp) that is the weights against those springs, and then ends at the stops.
on our car, my guess, ends at max torque. point. (IDK we dont have carbs here)
max hp is at 6000 rpm on g13, 5400 on g16
max torque is 3500 g13, and 3000 on g16.
so i bet the curve on the G15 for blue line goes to max at 3000 rpm. called the ALL IN , advance.
the pink line is based on many factors .
(smog, discounted)
1: engine displacement.
2: AFR (air fuel ratios) 12.5:1 is common, at tip in, if not carb is setup wrong.
3: compression ratios.
4: ratio of piston diameter to stroke,
5: what the mech, advance did.? (this is first rule inside dizzy,)
6: engine load, (hills, weight of car, etc)

my guess is your pink line all-in advance is totally wrong. due to G13 wrong part. for this car.

if you remove the vac, pot????
to say do racing (not ever racing below 2000 rpm)
the first step is to retune the mech, advance, the curve above tells you why.
and then tune the carb to match that.

note again how aggressive the vacuum advance is.... (all a function of the advance pot spring and carb ported vacuum port actions)
that vacuum pressure works against that spring, in complex way.....
this is why I said in the beginning
to put in stops on the vac pot, rod plate. if it goes to far, limit it, id never change static time, why do that?
static timing is for cranking, only.

on our EFI cars the idle advance can run 15 degree';s at 800 rpm, to save fuel....

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now the racing why? (they use custom efi now, but, back long ago...)
we put the distributor on the dizzy machine (SUN)
then remove the vac, advance, and lock the plate down so it can't move.
a pure mech, distrib now. (will work great if driven correctly)
then with a new set of racing weaker advance springs installed, we, get fast advance, sooner. way sooner. near 3000 rpm.
and last we carve up the weights to the total advance, so it can hit 35 degrees (or what ever the engine demands"book data")
but will ping, when you overload the engine, something that does not happen racing, say on a flat track.
on a street car , it does get overloaded on hills. or shifting wrong (m/t)
The stock car, normally ,the vacuum advance retards and the ping ends.(vacuum drops , on overloads)
that is about it , all ways, using no EFI spark systems.

[Swiftdoog]

I see, so advancing without vacuum won't give all the power, yet the power I feel is just the static timing being advanced in a slower ratr that it should be vacuum advance. But at the end of the mech advance (because i am advanced on static timing) I fall short on torque/power. I can't sense it because is just city driving. But if I take on a mountain road it will be noticeable.

Right?

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Oh, but then, why the engine feels better? I actually went on a trip today and there were more torque and the engine temp on hills stayed below 90°C (before it would climb near the 100°C).

Again, the timing being advanced maybe it did something but is not all what it should do.

BTW I just sae something on the old vacuum pot, the one that is damaged, it has a 20 stamped on the rod. Would that mean it advances 20°? Or it does 10 advance and 10 retard? Although the nipple is above the diaphragm so I believe it is a dual advance then.

[fixkick]

the engine can not make 5000 rpm just off idle, and do that and allow the mech, advance to take you there, it just rpm based.

vacuum is load sensing, the S-port , allows the vacuum advance to do that, it allows, the spark to advance way more aggressive than the simple RPM advance device.(centrifugal)

static is just base timing, all engines its must be near zero or engine will be hard to start.
once started, and running the 2 devices add up more advance, RPM and S-port vacuum tap.
algebra?

total advance = base static time + vacuum advance + rpm advance.(centrifugal fly weight device)

it is that simple, they just add up.
the engine is 95HP
if driving for beer , a lawn mower engine would do.
in fact timed any way at all would do. (if still starts)

what ive told here is to make it work under all conditions even 1000 lbs or bricks in back>
if i had it, and no time (labor) or cash to fix it.?

id retard the spark (base) until it don't ping, r (pinging is detonation and will wreck any motor,gas)
or
(or as you said, pinch the vacuum line, to dizzy)

the 3rd way ,is to put stops on the vacuum plate.
the vacuum servo moves the plate, all plates ive ever seen have stops.

here is how chevy guys do this, they get the mech, working correct first,: centrifugal )

then set the vacuum advance limits, the stock PLATE, has bent tabs to do that. and are crude and in your case dead wrong for any G13 vac, servo.
one could add a screw to form a stop but if drilled wrong , oops, cant correct that, now?
so they invented this gizmo... (your not the first to have this problem) (on my cars, its a simple ecu table edit)

see this gizmo.
it lets you limit total vacuum advance (stops). many vac, advances are too aggressive, (for sure with shaved heads, and high CR)

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the vacuum advance gives the engine its whole personality .
and for sure in town.
leaving a red light, (called OFF THE LINE, as in drag racing)
the advance is aggressive and huge engine torque happens now.
if no advance vacuum you just wait for 3000 or more RPM to get full torque.

only folks racing flat tracks take it off, (vac pot) because.
they never slow down
extra parts to fail
extra work tuning it
and risk of ping.
and last 2 devices to avoid killer ping... (they do hate it)

it's for stop light(sign) driving in town.
it gives you that magic, LOW END GRUNT,, "torque" (if carb setup right it does)

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the vacuum advance gives the engine its whole personality .
and for sure in town.
leaving a red light, (called OFF THE LINE, as in drag racing)
the vac advance is aggressive and huge engine torque happens now.
the mech centrifugal , is slow, unless you burn rubber down the block at every green light, hitting 5k rpm in an instant.
if no advance vacuum you just wait for 3000 or more RPM to get full engine torque.

only folks racing flat tracks take it off, (vac pot) because.
they never slow down
extra parts to fail
extra work tuning it
and risk of ping.
and last 2 devices to avoid killer ping... (they do hate it)

it's for stop light(sign) driving in town.
it gives you that magic, LOW END GRUNT,, "torque" (if carb setup right it does)