SPi to carb MINI conversion

Pray tell us all why you would want a timing light that flashes before the engine fires?

So using an average of several sparks to determine the trigger point? Trouble with that is the frequency is only about 8 Hz and the accuracy would be poor - especially with a less than perfect idle.

I also can't see the point. Pretty well every car engine has ignition occurring before TDC at all times, and will have a TDC marking, so the ability to dial in a suitable advance on a timing light is all that's required.

Thanks for confirming you haven't a clue about how a timing light works.

Or perhaps you'd give the make and model of your timing light that can preset both advance and retard?

It would be needed to preset a retarded figure on a timing light, in the same way as you *can* set an advanced one on some models.

How do you tell a mechanic from an engineer, from a scientist?

The mechanic thinks that "5=B0 advance" is a measurement in rotational degrees, because that's what the timing marks say.

The engineer thinks that it's 5=B0 phase difference, because that's what the plots look like, even if the engine isn't rotating at a constant angular velocity through the cycle

The scientist seems it as milliseconds, because they're thinking of the combustion chemistry, not the implementation as an engine.

If you do convert ignition timing to a time interval, then you'll find that ignition maps become a _lot_ simpler. Much of the "advance curve" only exists to map a constant time interval onto an increasing phase advance with increasing rpm.

It's not even that hard to do this, and to do it reliably for engines. All you need is a time-based predictor of engine rotation (a "time machine", if you insist) and you can do that much with a Kalman filter, which has been standard electronics design since the '40s.

Mazda multi-plug rotaries are the obvious counter-example. AIUI, they're workshop-timed from a fixed mark at 20=B0 ATDC, so they're always "advanced" of this, even if they're retarded from their notional TDC.

There have also been some lean-burn engines with retarded twin spark systems (I worked on electronics for development of one of these based on F*rd mechanics).

So can you give an example of a commercially available timing light that does what you say?

I really can't see the need for it. The need for a timing light is pretty well restricted to old vehicles anyway.

Quite obviously judging by your Klueless comments.

--=20 Conor

I'm really a nice guy. If I had friends, they would tell you.

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We did. THe best advice given was to take it to a roilling road of=20 which there are many throughout the country.=20

Even in Driffield, in deepest rural East Yorkshire, I know of three=20 within 30 miles.

--=20 Conor

I'm really a nice guy. If I had friends, they would tell you.

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No you tell us. You were the one with the futuristic light that we dont need!

Without a light with advance/retard function, or a timing pulley or flywheel marked off in degrees, can you suggest how the OP is likely to be able to find out what his basic advance curve is doing?

It was your retard light that I was talking about.. I have never seen one of those! I know its possible because I used to resell and use retard boxes for turbo boost retard, and used them to retard timing when on nitrous. And for what its worth you can map ignition without knowing anything other than the starting point. Just by looking at the power @ all rpm and throttle points and the exhaust gas. But with distributors, if you are trying to match a specific pattern you dont even do it on the car! You would know that though right? You use a small machine that drives the thing seperately and displays advance against RPM and vacuum. That only works if you have a stock engine including intake and exhaust, as well as "repeat" race engines.

No he didn't he wanted to know about his std mini fitted with a HIF carb not a H1F. I thought you knew about tuning engines ken?

Lets not complicate it for him by mentioning it may have different port shapes, valve sizes, valve seat cut angles and width, compression, manifolds, piston shape, cam timing and lift etc compared to the mini engine that originally used the SU carb. And thats before we consider different running temperatures and thermostats for emmission reasons, or different fuel! Plus the OP said it had different exhaust system and manifold I think, and a different induction system from the one a stock mini (which mini!!!) as well...

He couldnt make a bigger tit of himself if he tried.

I would say it would be pretty difficult to find a dyno operator, that knows how to set up a Mini properly.

Maybe you can suggest someone who would do the job properly for £60?

That would be extremely easy...............just copy the sort of utter piffle you come out with!

In your fantasy world the fact that all the nonsense you talk about would cost a great deal of money, doesnt really matter, as thats all it is, fantasy! However in real world terms people just cant afford to pay people (who are very often fuckwits like you!) to make your fantasys into reality!

One wonders if the OP has access to the equipment you have to hand in your fantasy world?

Funny, whenever Ken speaks the retard light comes on.

I am a dyno operator (and designer, builder) and tuner and an old A series is as easy as it gets! You are a joke.

If you say so. None of this stuff ever cost me a penny! I did it all from scratch and EARNED money from it. Not that the cost ever entered into it anyway. Thats just you thinking how YOU think. So you have no money either then!!!