ESE's works engine tuner

[TZ350]

Some more lovely odds and ends that are in the kit.

[rgvbaz]

If you are English that is 'You're'. Oh you are? How embarrassing.

Bugger that's embarrassing.

Dave

[Sketchy_Racer]

The EFI kits are great, mine worked straight out of the box.

The only problem I have encountered is it is VERY sensitive when you are burning a new map to the ECU, if it for any reason faults and wont start or will start but run funny, re burn the map to the ECU. Make sure you also earth everything well, I had issues with a crank trigger playing funnies because of poor earthing. Matt from Ecotrons seems very helpful and knowledgeable.

Cheers,

-Sketchy

[koba]

Ok, I was a bit confused too so I did some maths (if your American that's: math). The pic below has two curves on a Driving force v road speed graph. I guess you would never have anything like that in reality but to show the point... Both the areas under each curve (well straight lines) are 18 grid boxes in area yet curve A can accelerate the imaginary vehicle to 35 Km/hr in 2.22 secs Vs curve B which takes 4.17 secs.

I used the equations out of John Bradleys book for most of my spreadsheet.

Attachment 280864


Dave

Edit: Cum time = cumulative time not...

I've got a simpler method, it involves a stop-watch.

[koba]

I've been playing about with some workings out again.
From looking at other engines and results I've decided a really rough guide for inlet area on an engine of the type and power output we are looking at is around 190 to 200 sec/metre x 1000 @ 12000rpm.

Mine is likely around 110 in it's current state.
A Reed inlet seems infinitely more difficult to calculate and predict than a disk valve.
I think I can get mine to around 135 @ 12K in the same size reed cavity but that is all a guess and still woefully inadequate.

This is all from MOTA working out the effective area based on reed lift and all that, the max area for mine will be going from 12CM2 to 18.4CM2, still well short of the 26CM2 I think I may need.

This is crazy, madness made worse by my partial understanding.
Still I know I need to work on making what I have flow as much as possible for as long as possible.
I see where Frits got into the 24/7 idea.

More time, more numbers more thinks...

[TZ350]

The EFI kits are great, mine worked straight out of the box.

The only problem I have encountered is it is VERY sensitive when you are burning a new map to the ECU, if it for any reason faults and wont start or will start but run funny, re burn the map to the ECU. Make sure you also earth everything well, I had issues with a crank trigger playing funnies because of poor earthing.

Thanks for the heads up.

We have not heard anything for a while, how is your project going?

Matt from Ecotrons seems very helpful and knowledgeable.

Yes I have talked with Matt a few times by email, and even sent him a link to this thread in case he wants to check out what we are saying about his EFI kit.

[rgvbaz]

I've been playing about with some workings out again.
From looking at other engines and results I've decided a really rough guide for inlet area on an engine of the type and power output we are looking at is around 190 to 200 sec/metre x 1000 @ 12000rpm.

Mine is likely around 110 in it's current state.
A Reed inlet seems infinitely more difficult to calculate and predict than a disk valve.
I think I can get mine to around 135 @ 12K in the same size reed cavity but that is all a guess and still woefully inadequate.

This is all from MOTA working out the effective area based on reed lift and all that, the max area for mine will be going from 12CM2 to 18.4CM2, still well short of the 26CM2 I think I may need.

This is crazy, madness made worse by my partial understanding.
Still I know I need to work on making what I have flow as much as possible for as long as possible.
I see where Frits got into the 24/7 idea.

More time, more numbers more thinks...

I've got a simpler method, it involves a dyno.

[F5 Dave]

The EFI kits are great, mine worked straight out of the box.

The only problem I have encountered is it is VERY sensitive when you are burning a new map to the ECU, if it for any reason faults and wont start or will start but run funny, re burn the map to the ECU. Make sure you also earth everything well, I had issues with a crank trigger playing funnies because of poor earthing. Matt from Ecotrons seems very helpful and knowledgeable.

Cheers,

-Sketchy

Hey you've got a week to make it raceable (if that's a word). There's a Bucketing tradition.

Oh yeah I must drop your stator back.

[rgvbaz]

Thanks for that, Dave. I think I missed something. I will think that through. What happens if you take an acceleration vs speed graph with the same area instead?

Not sure?? I've melted my brain I will have a think/look if I get some time.

Cheers

Dave

[TZ350]

Posted because someone asked about the fuel pump details.

I think it is 25l/hr at 3bar and draws 2.5A, but it would pay to check the exact details and price with Matt.

Matt of Ecotrons info@ecotrons.com

[Sketchy_Racer]

Thanks for the heads up.

We have not heard anything for a while, how is your project going?

It's sitting waiting at the moment, I have finished the final-final design of the supercharger but in my interest to start machining prototype parts I decided to start my own company on the side and purchase a CNC mill and Lathe to setup making small custom components.

Soon there will be a cheap and easily available facility for custom cnc parts to be made for buckets

Hey you've got a week to make it raceable (if that's a word). There's a Bucketing tradition.

Oh yeah I must drop your stator back.

HAHA! Yeah it aint going to happen sorry mate, I've got the business above keeping me out of trouble at the moment and the Superbike is also keeping me broke and busy. Maybe a couple months time I will be able to get back into the bucket!


Cheers,

-Sketchy

[Frits Overmars]

I was a bit confused too so I did some maths (if your American that's: math). The pic below has two curves on a Driving force v road speed graph. I guess you would never have anything like that in reality but to show the point... Both the areas under each curve (well straight lines) are 18 grid boxes in area yet curve A can accelerate the imaginary vehicle to 35 Km/hr in 2.22 secs Vs curve B which takes 4.17 secs.

Let me add a bit to your confusion,Dave


The red curve B in your picture shows an initial power of zero HP at 5 km/h with a matching acceleration of zero m/s².
You claim a time of 4.17 s for the acceleration from 5 km/h to 35 km/h in. I claim that you will never reach 35 km/h because with zero acceleration at 5 km/h you will never get away from that first point of the power curve.

Have I got a different apoproach? Well....yes, but I published it on a restricted forum and it would be a deadly sin to bring anything at all from that forum into the open.
But what the heck, it was my own lecture and I hope they won't kick me out for publishing it here as well. So here is the full text (gimme a minute to prepare it for you folks. I'll be back).

[rgvbaz]

Let me add a bit to your confusion,Dave


The red curve B in your picture shows an initial power of zero HP at 5 km/h with a matching acceleration of zero m/s².
You claim a time of 4.17 s for the acceleration from 5 km/h to 35 km/h in. I claim that you will never reach 35 km/h because with zero acceleration at 5 km/h you will never get away from that first point of the power curve.

Have I got a different apoproach? Well....yes, but I published it on a restricted forum and it would be a deadly sin the bring anything at all from that forum into the open.
But what the heck, it was my own lecture and I hope they won't kick me out for publishing it here as well. So here is the full text (gimme a minute to prepare it for you folks. I'll be back).

I look forward to it
I'm sure if it's your work no one will mind

[Frits Overmars]

I decided to write this little story about power curve comparison after reading the following posts from fellow members AAAA and BBBB.

A 2000 rpm wide powerband at 5000 rpm is the same width as a 4000 rpm powerband at 10000 rpm once the gearing has been corrected to give them both the same performance.

If the rpm ratio is the same and the average power within the range is the same, the two powerbands would be "functionally equivalent". That is, a change to the overall gear ratio would make them perform the same...... The same average power over a given rpm range will produce the same average acceleration. It does not matter what the "shape" of the powerband is -- sloping upward, sloping downward, or flat.

I could not agree more, BBBB. But it requires a fundamental definition of 'average power'. And that is not 'the area under the power curve'.
Another one, also from BBBB:

Although we can narrow the powerband down to the absolute limit and have it show excellent results in a simulation like Dynabike, I'd want to have more margin than that for any application except maybe drag racing or bench racing. It is one thing to operate out front at "full speed" on the track, but traffic can cause you to operate in an undesirable part of the powerband. Similarly, recovering from a mistake (missed shift, forgetting how many downshifts a particular corner requires, etc.) is another reason we need a broader powerband.

Once again I fully agree and I would add that this could only come frome someone with actual competition experience. Any engine builder who thinks he can base his powerbands on the ratios of a gearbox, is not going to make his riders very happy - in fact he is not going to keep them very long.

Peak power alone does not say much about the usefulness of an engine. The combination of power curve and transmission, the sort of application the engine will be used for, and the abilities of the rider, together define which is the optimum engine character.

An example: a 125 cc road race engine can always be kept between 10.000 and 14.000 rpm thanks to its six-speed gearbox. Wether this engine produces 2 hp or 20 hp at 6000 rpm, is unimportant.
But a kart engine with direct drive without a gearbox has trouble staying above 5000 rpm in slow corners; it only can manage to do so by means of a very short gearing that forces the engine to rev over 17.000 rpm on the straightaway. For such a kart it is imperative that acceleration out of slow corners does not cost too much time. There may be only one such corner on the whole circuit, but time lost there cannot be made up by a higher top speed on the straight.
Therefore a sensible tuner will not concentrate on peak power; he will make sure that the power is never really bad in the whole range from 5000 to 17.000 rpm (in this kart-example).

I prefer to work not with a powerband but with a power range, which I define as the highest rpm of a power curve, divided by its lowest rpm.
Experience has taught what kind of power range is needed for a certain application. Road racing calls for a range of about 1.4 . When a CVT is involved, I imagine 1.2 over even less might be enough (though I'm only guessing here as I have next to no experience with these things). Motocross calls for something like 2. A touring bike needs at least 3 to be comfortable. And the direct-drive kart in the above-mentioned example needs about 3.4 (17.000/5000).

Let us asume we have a measured power curve from 7000 to 14000 rpm. That gives a power range of 2.
Within this power curve all possible range values are investigated, from range=1.00; range=1.01; range=1.02; etc, up to range=2.
For each of these range values the whole power curve is examined in order to find which lower and upper rpm values yield the highest average power.
For range=1.5 for instance, we start with calculating the average power between 7000 and 10.500 rpm. Then we proceed with 7010--10.515; then with 7020--10.530; and so on, until the final possibility of 9333--14.000 rpm. And the highest value found is stored as THE average power for range 1.5, together with its corresponding lower and upper rpm limits.

All stored values for average power are displayed in range graphs. So when you are preparing an engine that will need a range of 1.6 , you can see at a single glance which engine delivers the best average power at range 1.6 . Furthermore you can see between which rpm values this engine is most effective. And you don't need to fall into the trap that ALL engine builders have fallen into at some time: attaching too much importance to peak power.

Maybe you are used to comparing the acceleration times of different engines on an inertial dyno. But that only makes sense if these engines are all run between the same initial rpm and the same final rpm, AND all with the same gearing.
The range concept does not suffer from any of these limitations; it functions under all circumstances. And because you can compare the range graphs of all your engines, you'll be able to distinguish much quicker which range is best for a specific application. That is an experience you would otherwise only gather after years of trial and error.

Suppose you are preparing an engine for an application that requires a power range of 1.5. Then which of the two power curves below should you pick? Hard to say, isn't it? But when you look at the power range curves on the right, it is clear as day: the yellow curve wins.


Two more power curves. The yellow curve does not look very useful. But maybe it could work with a CVT.... The power range curve on the right tells us what we need to know. If the CVT can keep within a 1.2 rpm range, the yellow curve is OK. And if the CVT can keep within a 1.1 rpm range, the yellow curve is a winner!


Another advantage of the power range curve: it can show you the rpm limits you should operate between. At range 1.2 the yellow power curve works best between 9970 rpm (the blue curve) and 11.964 rpm (the white curve).

[Frits Overmars]

Earlier I claimed that average power is NOT the area under the power curve. A claim like this calls for an explanation, so here goes.

Take a look at the power curve above. It is a peculiar curve where at rpm-point E the power totally collapses, but then comes back. The reason I drew it like this will become clear in a minute.
We can look at the red area under the curve and convert that to a rectangle. The yellow rectangle in the picture below has the same area as the red areas under the original power curve. So you could say the average power between rpm-point A and rpm-point B has a magnitude equal to the height A--D. Or could you?

Let us put the engine with the peculiar red power curve in a vehicle and start accelerating, from rpm-point A to rpm-point B. How long will that take? It will take forever because the power at rpm-point E is zero, so acceleration at point E is zero; we will never get past that point. Acceleration from A to B will take an eternity which means that average power between A and B is zero!

Admittedly you won't encounter a power curve like the one in the first red picture very often. But the acceleration versus area argument holds for any power curve. Let's take a look at a 'normal' curve without a zero-power point. The curve below is split up into 9 equal rectangles, each with a horizontal dimension A--B that represents rpm, and a vertical dimension A--G that represents power.

When you convert the sum area of those 9 rectangles into a single rectangle with the same rpm spread A--F, it will have a height A--H that is 1.8 * A--G. Assuming A--G equals 1 HP, then the average power A--H would be 1.8 HP (picture below).

Now let us look at the same power curve and determine the average power via the acceleration approach. We will assume that acceleration from A to B with the available power A--G takes 1 second.
Between B and C the power is twice as much, so acceleration from B to C will take ½ second. And so on.
Total acceleration from A to F takes 20/6 s. If this acceleration were to have a constant value, it would take 1/5 * 20/6 = 4/6 s from A to B. This would require a constant power of 6/4 * A--G. Assuming again that A--G equals 1 HP, then the average power would be 1.5 HP instead of the 1.8 HP that came out of the area-approach...