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Just a quick question, if my engine is stock and I swap to a weber carb, should I use the stock timing settings? or it changes? just wonderin, since I will get my timing redone and I was wondering while using the stock setting the car felt lazy, but advancing it quite a bit the engine had good response, power and fuel economy, so, what gives then???
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If the engine is stock the stock timing should work the best.
Is the carb set up correct? jets,float?As far as I see yes, the thing is that I found 2 manuals about the same engine, one says 5 degress and the other states 6 degrees, both for 16 valve head (G16A carb model or FI). BTW the carb is brand new, the only thing I did was to increase the float level because the hole for the accelerator pump was above the level of the gasoline inside the bowl, and lauching from idle created a flat spot, also when doing a long turn to the right creates a flats spot, but I guess is due to that also.
I wouldn’t think you would need to mess with the timing. You need to be careful when you do make those adjustments however. You can actually cause engine damage if you get it wrong.
Keep us posted on how things work out for you.
Actually, this time I got it right, the thing is that all this time I was running my car at 0 degrees, that explains all the flatspots. Also thar my vacuum advance unit is adjustable, and Ihad to tighthen it quite a bit so it would not ping after 1500rpms (the original unit was damaged and I could not find a replacement). But right now is running quite much better, and throttle response is FI like. I really like the way it is now, it starts like a cigarrette lighter now. What I still don’t get is, why at 0 degrees the car felt nice?
Many engines are set up at 0º base timing, it just depends on how the advance is set up. It also depends on combustion chamber design, compression ratio, and the fuel used. There are many factors that contribute to how an engine performs and where it’s base timing should be set. I don’t know the specifics on your application however.
Hi, long time no see, did a few modification to the distribuitor vacuum advance unit (like changing the vacuum unit again) and I still have pinging while using the ported vacuum. I got my timing light now (applauses) and I noticed that as soon as I open the throttle, the timing goes up 10 degrees, from 6 to 16, and that doesn´t sound right; I mean, I thought that it should go more slowly, like 8 or 10 degrees. Does that number sound right?
[quote=”CarDoog” post=130770]Hi, long time no see, did a few modification to the distribuitor vacuum advance unit (like changing the vacuum unit again) and I still have pinging while using the ported vacuum. I got my timing light now (applauses) and I noticed that as soon as I open the throttle, the timing goes up 10 degrees, from 6 to 16, and that doesn´t sound right; I mean, I thought that it should go more slowly, like 8 or 10 degrees. Does that number sound right?[/quote] Rate of advance depends on a number of things including the vacuum advance canister specifics and the springs and weights in the dizzy. As you hit the throttle, the amount of advance will decrease(positive pressure replaces negative) as the mechanical advance takes over(RPM based). The rate of mechanical advance is in the springs. You want the most advance without pinging. Without knowing what weights and springs AND the canister specs, its hard to tell if those numbers are good. I run ported vacuum with 6 degrees base timing. My vacuum canister is adjustable(it’s on max adance) and my weights are stock with max tension springs to hold full mechanical advance off until 3k rpms where I’m all in at 32 degrees total advance. Every engine is different, so “normal” is relative.
Exactly, in my case, my canister seems to act weird, for example, if I set 0degrees initial timing to do the test, if I slightly move the throttle like a hair (800 to 900 rpm) I see an advance of 4 degress, but moving further I get 15 degress, what bothers me is the curve, like is way too fast and my canister is not adjustable, that’s way I have the doubt, if I set my advance to 6 degress (factory), as soom as I touch the gas I get ping, (1200rpm and further). So I want to know if swapping the carb affects timing and if I need to reshape the whole thing (harder springs maybe) for a more soft advance vacumm advance? Does that sound right?
[quote=”CarDoog” post=130835]Exactly, in my case, my canister seems to act weird, for example, if I set 0degrees initial timing to do the test, if I slightly move the throttle like a hair (800 to 900 rpm) I see an advance of 4 degress, but moving further I get 15 degress, what bothers me is the curve, like is way too fast and my canister is not adjustable, that’s way I have the doubt, if I set my advance to 6 degress (factory), as soom as I touch the gas I get ping, (1200rpm and further). So I want to know if swapping the carb affects timing and if I need to reshape the whole thing (harder springs maybe) for a more soft advance vacumm advance? Does that sound right?[/quote] The vacuum advance should still be active until the throttle is open to the point where vacuum ceases to exist(or is too low to actuate the advance). It really depends on the canisters specs as I’ve said before. For example, the canister I have on my distributor at max setting starts applying advance at 7 inches of mercury(7hg) and that is the minimum for some advance. So lets do the math here, initial timing at 6+5 degrees of vac advance at 7hg=11 degrees of advance(not including mechanical). By this time, the mechanical advance is already there rpm increase and throttle opening, with heavy springs(which help prevent pinging) and the weights, advance is all in by 3.2k rpms while vacuum advance is at 0. I would say your curve is too quick and you need to look at both the canister and springs. I would move to a heavier spring. Changing the carb will do nothing for ignition timing as carb tuning is directly related to ignition timing. You also do ignition first, the carb is based of of ignition.
Just to see if I get this clearly, I have need the timing right to get the carb right, but at the same time, I need my carb to be right so my timing doesn´t feel weird, right?
I say this because I was thinking about as I was traveling today and I it hitted me, my old carb, as I recall correctly, had a quite weak ported signal, the tubing was quite small (apparently it was designed that way), compared to the weber´s, and thinking about it, could it be that I am using the canister for a carb that has a soft ported signal, and now that I have the weber and I get quite a strong vacuum I am getting advance way too early, instead of building up as it just to do with the older one (it was crap anyways so I believe it had something do to too).
Also, as I was going through the mountains, I decided to really feel and listen to the car, I did all the trip (aroumd 187km back and forth) only using the primary side of the carb, I feel that the car has enough power to pass going uphill with just the primary (remember that I am not using the vacuum advance and I am at 10-12 degrees mechanical advance) and I thought “the power band shifted because of the advance, but why I am getting the power that I need by just using the primary? and why do I get ping as I open the secondary?”, I also thought “could it be that I need to almost overlap the vacuum advance to the mechanicall advance, so that I get the advance I need from the vacuum and then at certain point the mechanical takes over, like getting from 0 to 6 degrees in vacuum and them 6 to whatever number goes in the mechanical?”
Does that sound right?
[quote=”CarDoog” post=130954]Just to see if I get this clearly, I have need the timing right to get the carb right, but at the same time, I need my carb to be right so my timing doesn´t feel weird, right?
I say this because I was thinking about as I was traveling today and I it hitted me, my old carb, as I recall correctly, had a quite weak ported signal, the tubing was quite small (apparently it was designed that way), compared to the weber´s, and thinking about it, could it be that I am using the canister for a carb that has a soft ported signal, and now that I have the weber and I get quite a strong vacuum I am getting advance way too early, instead of building up as it just to do with the older one (it was crap anyways so I believe it had something do to too).
Also, as I was going through the mountains, I decided to really feel and listen to the car, I did all the trip (aroumd 187km back and forth) only using the primary side of the carb, I feel that the car has enough power to pass going uphill with just the primary (remember that I am not using the vacuum advance and I am at 10-12 degrees mechanical advance) and I thought “the power band shifted because of the advance, but why I am getting the power that I need by just using the primary? and why do I get ping as I open the secondary?”, I also thought “could it be that I need to almost overlap the vacuum advance to the mechanicall advance, so that I get the advance I need from the vacuum and then at certain point the mechanical takes over, like getting from 0 to 6 degrees in vacuum and them 6 to whatever number goes in the mechanical?”
Does that sound right?[/quote]
Simple answer, both have to be correct for proper engine running. When doing a tune-up, you always do ignition first because the carb tuning is affected by the ignition. As a good example of what can happen, I had two issues with my truck a while back: one in the carb and one in the ignition(the vac advance). I had a bog at part throttle and I wondered why. So, I rebuilt the carb new accel pump seal fixed most of the problem(ethanol ate the original seal right on up). After the rebuild, the bog was gone, but there was still a part throttle hiccup. I realized the vac advance was busted by seeing if it held the rod when vacuum was applied..it didn’t fixed and the hiccup went away permanently. They both have a close relationship and both have to be in top order for proper engine performance.
Back to your pinging situation, it is quite possible you are running too lean. Running lean raises combustion temps. You may be getting too much air when the secondaries open and not enough fuel. As for the ported vacuum, the smaller port increases velocity and creates a stronger vacuum signal than a larger port. We are talking volume vs velocity here. The bigger the space, the more volume air can be drawn into it, however it reduces the airs velocity. I would run the stock carb. Its possible you are overcarbing your engine. Without seeing, hearing and diagnosing it in person, it is difficult to say for sure what will and won’t work.EDIT: I also see you HAVE made some mods that may be contributing. Iridium plugs on a 95, unless recommended by Suzuki or MSD don’t sound right to me at all. The biggest red flag to me is the exhaust mods. If you made the exhaust more free flowing, you will run leaner and combustion temps will rise. So when you are higher rpms under load and open up the secondaries, you may get ping. I am not familiar at all with Suzuki but I am very familar with carbs, fluid theory and ignition timing among many other things. I am basing what I tell you off of my knowledge and experience. My 454 is a world apart tuning wise than you 1.6, but the theories and physics remain the same. MSD coils, if I remember correctly, require a larger spark plug gap, and extra resistance in the ignition circuit. I’m also not 100% positive because you live in Venezuela, but here in the states, carbs were done away with in 91 with subaru being the last to offer one in a mass produced car if memory serves correct. Ignition also became computer controlled in the 80s here, not sure about Ven.
Ye, actually I did the mods because of the scarcity and costs of spare parts, plus recently all the problems with inflation has made it almost impossible to properly mantain a car.
About the lean situation, and overcarbing, I want to explore that with the following premise: the other carb (long gone btw, was busted) was only one barrel, and the weber is two barrel, also I upgraded to weber using the kit from a Toyota Tercel, which are by a amazing coincidence, exact match on manifold shape, also because the Tercel is 1.5 and mine is 1.6, and I thought last night while sleeping about an old Toyota Corolla 1986 a friend I checked once for a trouble, has with a carb that I believe is an Aisan, but two barrel also, it did something particularly interesting, as I opened the primary as saw the fuel flowing through the ventury going down into the barrel.
In my case, I see the same on the primary side of my weber, but on the secondary (doing this manually at home btw), touching the secondary lever just a bit it raises the engine speed, a little further and the engine raises and it does a little shaking, kinda like fuel starvation, and then little bit more and then I see fuel going through the venturi. (is it ventury or venturi?)
Is something that I have been thinking about it since while doing the trip (I kinda feel now when I am actually opening the secondary), I didn´t use the secondary at all, could it be that, as you say, I just need to live with a one barrel carb, maybe disconnecting the linkage and using the primary only? I can hit 120km/h only using the primary at 1/3 to 2/3 or throttle travel on flat road, and the car feels powerfull.
Also, about the mod, I just change the manifold configuration from a 4-2-1 to a 4-1, but the piping size is the same actually, also the spark gap was indeed increased (0.7mm if I recall correctly, I thought it was too much but indeed it runs quite good), and the coil, there are older models that have actually a coil like that, mine came with a dry coil (dry?, I mean, one that doesn´t have oil, don´t know the name in english, but it was smaller), so I just swapped it to the MSD and actually the improvement was in the starting time, no more overcranking.
Also, I do have pictures, let me add them, by the way, everyone tells me that what I have actually is one of a kinda, because that engine (that is the same on the old Vitara and Tracker) comes with an FI, but apparently here on the South, they decided to remove the FI on those models and go with a carb. As you can see, oil prices affect the development of vehicles a lot down here.
I truly sure that if that vehicle was FI, I won´t be here 😛 so I am rather thankfull that is it a carb and I got to find a place where I can get a hand to survive with it 🙂
First, the videos, I did record part of the installation process, long time ago now (actually a year ago :P)
[video]https://www.youtube.com/watch?v=4-ldPE3bKkw[/video] that´s a quick shot of the old carb, as you see is the same as one some Tercel have, and believe me, that carb withouth all the stuff that it should have that I seen on the Tercel is just a piece of…From here on, is just Weber (BTW, if you post videos with https it doesn´t show, I had to change it to http)
[video]http://www.youtube.com/watch?v=GzmZeowZwGQ[/video]
[video]http://www.youtube.com/watch?v=s4OJRWzlA30[/video]
[video]http://www.youtube.com/watch?v=CAvObXbiPDE[/video]In the pictures you can see how is it installed and the old canister, it was from a Fiesta (what I could find that would fit, but it was too big and I could only set the timing to 6 degrees hardly, as the canister colided with the temp sender), the new canister has only one diagrahm instead of two, apparently all the canister I can find just advance timing, I haven´t found any that can retard.
Also, before going further, my jets are all stock:
Idle: 60
Secondary idle: 50
Primary and Secondary:140
Air Primary:170
Air Secondary:160
The emulsion tube: F50
The rest is pretty all out of the box.Here is my take on it, you are overcarbed for that little 1.6, no doubt about it. That’s why when you are on the primaries everything is running great…until you open the secondaries. So we have two options here that I think will suffice:
1. Get a comparable/compatible 1 barrel carb
2. Block off the secondaries, you don’t need them on this enginePS: The proper word is venturi, as in the venturi effect. I truley am of the belief that your issue is in the carb as you say you have enough/normal power AND no pinging when the primarys are on, yet problems when the secondaries open. This leads me to believe that since your engine was designed for a one barrel and you are running a 2 barrel, you are overcarbed(only when the secondaries are open. What was the CFM on the original carb? As I said I’m not really familiar with Suzuki.
PSS: You say all the jets are stock, does that mean stock to the original specs/one barrel carb? Or to the two barrel specs? Undersized jets will lead to the lean condition. When running more free flowing exhaust, especailly headers, you are running leaner so increasing the jet size is what needs to happen. In your case, we are working with quite a few variables.
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