flat spot at speed changing to 3rd 4th TIMING ?

[mk1mini]

You started going on about the shape of the rest of the curve, part throttle, performance distributors, aldon red and yellow dizzies. Two and three Dimensional mapping, vacuum advance, too much advance, your 1380, your 1480 that you've had 276, 286 and how ever many other cams. Cooper 'S heads, Ambient temperature, charge temperature, octane ratings, need I go on.

In fact you talked about so much stuff you convinced the op you knew what you where talking about.

Now that, I am in full agreement with

Iv not been convinced of anything , I don't know what cam / needle / internals I have. I restored the car myself 4 years ago and I am a competent engineer... but engine timing and the engine in the car was nothing to do with me . I'm just trying to find out how to time the car and get it set up correctly {or near too with the components I have as I know it all works and wasn't far away to begin with}

The only reason im into this is that I changed the points and set them up with the dwell angle..... which lead to wanting to get the overall timing better and more accurate .

I usually just rock the car back and forward to 10 degrees btdc and leave it ! wish I had just done that now.

[ianh1968]

Judging by the way you tune your motors.

erm... on a rolling road? Certainly not remotely, without a full spec, via an internet forum!

This is the trouble with most mini forums, people feel they know what there talking about.

Hear, hear!

You started going on about the shape of the rest of the curve, part throttle, performance distributors, aldon red and yellow dizzies. Two and three Dimensional mapping, vacuum advance, too much advance, your 1380, your 1480 that you've had 276, 286 and how ever many other cams. Cooper 'S heads, Ambient temperature, charge temperature, octane ratings, need I go on.

This is because all this stuff is relevant to the tuning of an engine.

Now all of a sudden you can't read plugs!

Again, sorry for my total ignorance, but what I said was that I can't read plugs with virtually no burn on them.
Anyhow, I don't need to, I use a dyno...

Sorry to say this, but maybe you should of just kept quiet and just possibly you'd have learn't something.

Does this win the prize for the most patronising remark made on a friendly forum so far this year?


Ian

[mk1mini]

[swifty]

5 pages now . With the two of you going back and forth . I appreciate your trying to help , but can't help thinking all you've managed to do is confuse the fella .

[Smiffy]

erm... on a rolling road? Certainly not remotely, without a full spec, via an internet forum!

Which was why I asked for the spec first, it wasn't fully know. So I proceeded to describe how the OP should tune his mini.

This is because all this stuff is relevant to the tuning of an engine.

So exactly why was you mentioning what you've done in the past.

Again, sorry for my total ignorance, but what I said was that I can't read plugs with virtually no burn on them.
Anyhow, I don't need to, I use a dyno...

I see a problem, a dyno won't tell you what the mixtures doing. It's just a device for measuring power, it can tell you if one settings is better than another. But doesn't tell you anything about the actual mixture.

Does this win the prize for the most patronising remark made on a friendly forum so far this year?

Ian

Don't know think the above dyno comment is pretty good and remember ian it's all said in the best possible taste

[mk1mini]

I was wondering the same, so many people say dyno but how can a dyno see the colour of sparkplugs or mixture setting, just because its running a high output doesnt mean you arent melting internals..... The gunson colourtune has also been mentioned but even though you could use it at different rpm ranges there would be no load on the engine. Any input ?

[ianh1968]

but how can a dyno see the colour of sparkplugs or mixture setting

The actual dyno itself doesn't, but most if not all workshops that have invested
big money on a dyno will also have mixture diagnostic equipment as well.

It would be like having a school, but with no teachers...

I certainly would not bother paying to use a dyno if it did not have this equipment.

Gunson ColourTune: but even though you could use it at different rpm ranges
there would be no load on the engine. Any input ?

This is why in most instances, especially with a tuned engine, it is not
considered to be a reliable method of calibration.

It is also not really designed for long term use, mainly because of how
it gets connected up, and also the fact that the "heat range" is not known.

I bought one years ago when I was first starting out but have not taken
it out of its box for maybe 25 years.

Ian

[mk1mini]

The actual dyno itself doesn't, but most if not all workshops that have invested
big money on a dyno will also have mixture diagnostic equipment as well.

It would be like having a school, but with no teachers...

I certainly would not bother paying to use a dyno if it did not have this equipment.

This is why in most instances, especially with a tuned engine, it is not
considered to be a reliable method of calibration.

It is also not really designed for long term use, mainly because of how
it gets connected up, and also the fact that the "heat range" is not known.
Ian

surely the diagnostic equipment would be stuck up the pipe , that would just give an average reading and not each individual cylinder ?

[ianh1968]

surely the diagnostic equipment would be stuck up the pipe,
that would just give an average reading and not each individual cylinder ?

Well, yes, but it's how pretty much all tuning is done. Posters on my own
"Mixture Analysis" thread have said before that the "Plug-Chop" method is
not very accurate and should not be relied upon.

Although there will be slight differences between the cylinders, at the tuning level
that most of us here are at, this would be of little consequence.

Ian

[Spider]

'Plug Chop' is a valid and useful guide for getting quite close with fuel mixtures under steady state conditions and can also be used to aid with sorting ignition timing, however to be able to read the plugs to sort the latter takes a few years of experience, it's not something that someone is going to be able to read about and then just do straight out of the box.

I will go a little further to say that 'Plug Chop' is useless in sorting problems under dynamic (that is 'changing') conditions, like Acceleration for example or just changing revs / load from one range to another.

Which brings this back the the OPs Question - A Flat Spot under acceleration. This is going to be far more likely to be a fuel problem than one of ignition timing and considering that it is a problem that is occurring during a change of state, you can look at spark plugs until the cows come home, but the flat spot will most likely still be present. I also note that the OP has 'fiddled' with ignition timing to no avail.

First, is the coolant getting up to the right temp?

Has the engine ever been Dynoed to get things like Mixtures, Ignition Curves, Timing sorted and Plug Heat Range? Apologies if these may have been answered earlier.

[ianh1968]

Spider, the "Plug-Chop" I was referring to was the "30 seconds thrash on brand new plugs"
variety, previously described.

I think we both agree that a "steady state" chop, which will have had the engine running
for a reasonable amount of time at a constant load/RPM before the cut, can be helpful...

Ian

[Smiffy]

"Mixture Analysis" thread have said before that the "Plug-Chop" method is
not very accurate and should not be relied upon.
Ian

Just for some CLARIFICATION on ianh1968 view

Again, sorry for my total ignorance, but what I said was that I can't read plugs
Ian

[mk1mini]

Which brings this back the the OPs Question - A Flat Spot under acceleration. This is going to be far more likely to be a fuel problem than one of ignition timing and considering that it is a problem that is occurring during a change of state, you can look at spark plugs until the cows come home, but the flat spot will most likely still be present. I also note that the OP has 'fiddled' with ignition timing to no avail.

First, is the coolant getting up to the right temp?

Has the engine ever been Dynoed to get things like Mixtures, Ignition Curves, Timing sorted and Plug Heat Range? Apologies if these may have been answered earlier.

spider, the flat spots are now gone thanks to smiffys suggestion on a timing setting , I am now needing to adjust the mixture if needed now the timing is a lot better , its even starting nearly instantly but I am able to put the choke in nearly all the way from a cold start after afew seconds which makes me think the mixture IS needing adjusted anyway. The car hasn't been dyno'd and runs a standard 59d and BR7ES plugs btw and the engine {top hose} does run up to temperature before I drive it usually unless im in a hurry

smiffy, you have quoted me saying something that I never {above} it was your internal friend in combustion that said that quote

[ianh1968]

Just for some CLARIFICATION on ianh1968 view

Again, sorry for my total ignorance, but what I said was that I can't read plugs
Ian

A classic case of "Selective Quoting" where the poster leaves off part of
the text deliberately in order to deceive others and change the context
of what was being said...

The un-edited quote was this:

Again, sorry for my total ignorance, but what I said was that I can't read plugs with virtually no burn on them.

Smiffy:

I defer to your obviously far superior knowledge (on probably every subject, past, present, and yet to be discussed)...
I shall not waste any more of my time making further posts on this thread.

Ian

[Smiffy]

Just for CLARIFICATION this is also what you said

I am quite happy to admit that I can't do it... What's the problem?
Ian