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hspeck

X180 2.2 NA ignition timing

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12 minutes ago, slewthy said:

I really like this thread.

Despite having taken my engine out a couple of times, changed the cambelt, checked alignment, timing, combustion, have the books, read the guides, manuals etc etc, I am learning lots and not ashamed to admit it. It sometimes just takes a different way of explaining I guess?

HsPeck is doing well - has taken both advice and criticism with good grace and is clearly a little isolated where they are, yet keen and determined to understand, progress and hopefully succeed. And all with the help of the forum (and FB, whatever that is...) This is what its all about I think.

We all had to start somewhere and best to begin where there is willing help a-plenty. 

It never hurts to start at the beginning - "explain it to me as if I were a 7 yr old" [MichaelScott - he did then downgrade it to a 6 yr old 😂]

We all have differing levels of understanding of things, and confidence limits within which we tend to assume others reside. Thats not always the case, as I have discovered to my cost over the years. I am also grateful to those who have cut me some slack when I'm trying to understand/do something outside my ken.

 

 

 

We all  have to go through the learning process. No one should be too proud to say I start by crawling, then walking, running then jumping. But if we jump before we learn to walk, then we are gonna hurt ourselves in a big way. Better to go, slow and not break out necks. The people who aren't willing to impart knowledge  are not meant to be on this Forum.

OP is shining a hi-tech timing gun all over the place like a Star Wars light sabre. Ain't gonna do anyone any good. ⚔️

Edited by ekwan

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So today i did some testing on the car.

1. First thing i did was I checked the ignition timing again. It was still 20° BTDC. My friend helped me to rev the engine anf i registered the timing as approximately 30° BTDC at 2000rpm and 40° BTDC at 3000rpm. And then i crimped the vacumm hose at the vacuum capsule and checked again at idle. It was also 20° BTDC. If i have done it correctly, it seems there is no difference. The distributor only has 1 inlet for vacuum.

2. Then i rotate the engine to TDC. The cam pulleys' marks align at the middle as per the manual, and my friend helping me confirmed that he felt pressure when the cam pulleys' mark are aligned. I assume this is how we check if the cylinder 1 is on the compression stroke.

I removed the distibutor cap and saw the rotor position as in the 1st photo. The rotor is pointing to the no.1 plug lead position.

Then i rotate the engine again till my friend feels compression at cylinder 4 and that is the 2nd photo.

I kind of realised now as i think over it that i should have removed the rotor to check the reluctor projection and pick up aligned.

I then turned the engine again to reconfirm the position of the rotor arm at TDC.

I am not sure if it correctly shows the static timing as I did not look below tge rotor arm.

3. I then decided to rotate the distributor 80° clockwise and shift the plug leads 1 position anticlockwise. So plug lead 1 is at the original no. 3 position, 3 at no. 4 position, 4 at no. 2 position and 2 at no. 1 position.

I then rotate the distributor until the vacuum capsule hit the oil filter.

The ignition timing at this position is 10° BTDC.

 

 

 

20181208_155959.jpg

20181208_155711.jpg

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Sorry had to stop short as family duty calls.

So the maximum timing i could get was 10° BTDC after i rotated the distributor and moved the plug leads 1 position anticlockwise.

I then redo the idling and balanced the carb according to the manual.

One thing i realised is that the readings on the manometer is much lower. Previously the readings at 20° BTDC were around 178 but now they were around 160.

I am not sure what that means and may imply.

I did not notice any significant difference before and after i rotate the distributor during idling.

However, when i drove the car, i could feel some hesitation, at 2nd gear, and the car does not seem to pull as strongly and smoothly as before. Also, previously the exhaust 'pop' occasionally, but now the exhaust 'pops' through 2nd, 3rd and 4th gear. It happens when i release the gas to shift the gears.

It may be because i was in a rush when i was tuning the carbs, but the difference in how the car feels at 20° BTDC and 10° BTDC is quite pronounced.

I will try to check the tuning again tomorrow and update. Maybe reposition the distributor back to the original position too if time permits. Fortunately i was reminded by fellows here to mark the position of the distributor prior to me rotating it. So hopefully should not be too much problem.

Appreciate any thoughts and what i might have done wrong.

The photo is the ignition timing after I rotated tge distributor and adjusted the timing gun to 10° advance.

Thanks.

20181208_174233.jpg

52 minutes ago, slewthy said:

I really like this thread.

Despite having taken my engine out a couple of times, changed the cambelt, checked alignment, timing, combustion, have the books, read the guides, manuals etc etc, I am learning lots and not ashamed to admit it. It sometimes just takes a different way of explaining I guess?

HsPeck is doing well - has taken both advice and criticism with good grace and is clearly a little isolated where they are, yet keen and determined to understand, progress and hopefully succeed. And all with the help of the forum (and FB, whatever that is...) This is what its all about I think.

We all had to start somewhere and best to begin where there is willing help a-plenty. 

It never hurts to start at the beginning - "explain it to me as if I were a 7 yr old" [MichaelScott - he did then downgrade it to a 6 yr old 😂]

We all have differing levels of understanding of things, and confidence limits within which we tend to assume others reside. Thats not always the case, as I have discovered to my cost over the years. I am also grateful to those who have cut me some slack when I'm trying to understand/do something outside my ken.

 

 

 

Thanks for the encouragment! Learning new stuffs at 49 like a 7 year old is never easy... But next time i will start with that statement... Hahaha

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Looks like you've now established that cam timing is good, and you've achieved 10BTDC.  You've done nothing wrong!  These 2 settings are absolutely necessary; don't try to adjust them to improve performance (there are scenarios when you could, but that's not to be considered at this point).

It's entirely possible that too much advance could increase performance, but at the risk of longer-term damage to your engine.  You now need to look much more closely at your ignition advance and carb setup.  Either find a good reference for carbs, or locate an expert.  Getting carbs balanced correctly is quite a task.  Also, these engines do like to run a little on the rich side.

One other variable:  have you checked valve clearances?

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1 hour ago, Sparky said:

Looks like you've now established that cam timing is good, and you've achieved 10BTDC.  You've done nothing wrong!  These 2 settings are absolutely necessary; don't try to adjust them to improve performance (there are scenarios when you could, but that's not to be considered at this point).

It's entirely possible that too much advance could increase performance, but at the risk of longer-term damage to your engine.  You now need to look much more closely at your ignition advance and carb setup.  Either find a good reference for carbs, or locate an expert.  Getting carbs balanced correctly is quite a task.  Also, these engines do like to run a little on the rich side.

One other variable:  have you checked valve clearances?

Thank you Sparky.

So you are saying I should not revert back to 20° BTDC.

I do realised that the car likes to run a little rich.

I will try to readjust tomorrow. If i cannot get it to run smoothly i will have to send it to the tuner. Hopefully i will be able to learn a thing or two from him.

As for the valves, i dont think i will ever be able to tackle that. Best to leave it to a competent workshop.

In the meantime my search for a competent workshop continues. 

My friend refused to service my car.. Hahaha.. Too much effort for the money he claims..

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1 hour ago, Sparky said:

Looks like you've now established that cam timing is good, and you've achieved 10BTDC.  You've done nothing wrong!  These 2 settings are absolutely necessary; don't try to adjust them to improve performance (there are scenarios when you could, but that's not to be considered at this point).

It's entirely possible that too much advance could increase performance, but at the risk of longer-term damage to your engine.  You now need to look much more closely at your ignition advance and carb setup.  Either find a good reference for carbs, or locate an expert.  Getting carbs balanced correctly is quite a task.  Also, these engines do like to run a little on the rich side.

One other variable:  have you checked valve clearances?

That would be terrible......🤑

505712086_Screenshot2018-12-08at8_40_43PM.thumb.png.3d2e00d893a0590a567edda3ab919dba.png

 

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7 hours ago, ekwan said:

Under these conditions, there is little (if any) vacuum. After all, if there is liquid flow of any kind, there must also be present,  a pressure difference, albeit great or small (no pressure differential, no flow....logical, plus a whole bunch of engineering mathematical equations). At idle, the minuscule amount of vacuum (if any) is probably insufficient to shift the vacuum diaphragm against the spring forces within.

Surely, a closed throttle creates maximum inlet tract depresion (vacuum)? It can be measured with a manometer & you can then watch the mercury levels drop by opening the throttle allowing air to flow into the cylinders & diminishing the vacuum. The old Ford Prefect had vacuum powered windscreen wipers which stopped working when the engine was labouring because there was no manifold depression to power them.

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1 hour ago, jonwat said:

Surely, a closed throttle creates maximum inlet tract depresion (vacuum)? It can be measured with a manometer & you can then watch the mercury levels drop by opening the throttle allowing air to flow into the cylinders & diminishing the vacuum. The old Ford Prefect had vacuum powered windscreen wipers which stopped working when the engine was labouring because there was no manifold depression to power them.

Due consideration must be given to the location of the ignition vacuum take-off in relation to throttle plate.

You are correct in saying that by opening the throttle diminishes the vacuum. Simply because the vacuum take-off for the manometer measures vacuum of the idle circuit only. When the throttle plates are gradually, air-fuel mixture goes from the idle phase to progression and finally to the main circuit. 

............and with that, I am done with this thread. 👋

 

Edited by ekwan

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1 hour ago, ekwan said:

............and with that, I am done with this thread. 👋<span>

You'll be back I just know it, you can't resist, resistance is futile.

Thanks for the recommendation for those Brembo pad retaining pins, they arrived today, much appreciated. 

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It is clear to me there is room to clarify on the understanding of vacuum, which is a measure of the absence of matter within a space, and flow, which is a measure of the rate of a material volume passing through a space. A spark ignited engine, that is all Lotus engines so far,  is controlled by way of throttling the airflow through the intake tracts. At full throttle there will be no vacuum in the intake tracts through most of the operating rev range, and the motor will pull at maximum force against a load. When we wish to subdue the motor we throttle back on airflow creating a substantial vacuum in the tracts downstream of the throttles and so starving the motor of power. At equilibrium, where the revs are constant, there will be air and metered fuel sufficient to balance against the load. When at idle there is minimal load therefore minimal flow of air/fuel but the vacuum will be high. The vacuum will be still greater when off throttle, in gear on overrun. The vacuum capsule on a distributor when used in the most basic manner serves to add advance for the sake of improved burn of the air/fuel charge, as this takes longer to burn in a state of diminished density. The specified static and maximum advance figures are to be scoped with the vacuum capsule offline, and the vacuum port or hose stopped up against leaking. Think of the vacuum advance as a useful adjunct, to be dealt with independent of the mechanical spark settings and usually a matter for no adjustment of its own. So disconnect when working through the advance settings then reconnect when those are right.

To the matter of Hspeck's Esprit it is better that the overall spark advance is reduced from 40°, to be sure. Something like mid - 30's maximum advance, all in by 2500 - 3500 is likely correct for the motor. Idle advance is best targeted to factory ranges but is not critical so should be subordinate to the maximum figure. Idle air/fuel mixture is whatever makes the motor happy, unless dictated by emissions testing authority. With the timing now reduced there will be need for some further tweaking of the carb idle throttle and mixture settings, as the previous advance setting would have altered the burn. There will be no need for great changes to carb or distributor settings as related to factory, however there is room for some improvement and certainly fine tuning for the fuel characteristics specific to Singapore. It's good and necessary that the baseline state of the engine is being established correctly.  

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20 hours ago, ekwan said:

Simply because the vacuum take-off for the manometer measures vacuum of the idle circuit only.  

............and with that, I am done with this thread. 👋

 

The manometer measures the vaccum in the cavity between the piston crown & the back face of the butterfly which results in a compession ratio of less than zero to one when the throttle is closed as there is virtually no air entering.

So I wonder why done with the thread. 😃

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