ESE's works engine tuner

[TZ350]

The Christmas project ..... to see if we can crack 30+hp

Not quite 40 hp, as I can't get my triple port cylinder re bored over the break and probably wouldn't get a Frits pipe made in time either so its a refinement of what I have thanks to EngMod2T's help. Means gluing the transfers to reduce the trans duration and depends very much on how much I can improve the air flow through the carb.



Simulated crank hp. Drop something for transmission loss and some more for workmanship and it still might be possible to crack 30+ at the rear wheel with what I already have, with any luck, 31-32.

Conventional setup, old RS pipe, Single exhaust port opening 79deg ATDC, Trans 117ATDC Inlet 145/90 and a new style of 24mm carb.

Ill post the dyno graph when its done ...

[Grumph]

TZ - you mentioned a plenum a couple of posts back....more information please. i've wondered whether the 24mm restriction could be overcome with a heimholz resonator inlet plenum....

Singh slots - I can't see any possible value in a 2 stroke application. Biggest value in a 4 stroke is creating a barrier at overlap to prevent charge loss out the exhaust. A jet of oily mixture aimed at the plug around ignition could well cause problems.

[bucketracer]

TZ - you mentioned a plenum a couple of posts back....more information please. i've wondered whether the 24mm restriction could be overcome with a heimholz resonator inlet plenum ....

TeeZee's 1.2L Plenum ... 24mm carb 34mm inlet from the plenum to the crankcase ...



Old vids of the Plenum being tried out in the drive.



34mm inlet feeding ready to burn mixture to the crankcase, a good idea, and it worked in so much as the bike ran OK but not usefull because in the end it was not the carb that was restricting the power but insufficent blowdown time area.

TeeZee thinks that when he gets to the limit of a conventional 24mm carb he will look at the plenum again.

[wobbly]

NGK race plugs were originally designed to be about 1mm proud of the chamber,one reason there are no threads on the shell end.
This leads on to one reason that a toroidal chamber design works best.
I believe that plug position and indexing effects are reduced considerably by the quality of the CDI and the energy in the gap.
Using Ignitech and 0.2 Ohm primary Aprilia RS250 ( RGV) coils, I tested plug indexing and found no difference - but the fine wire R7376-10 plug made near on 2 Hp in 50 against a
Denso RS125 plug and a B10EGV.

TeeZee, use the new pack and go feature and send me your files - I will get bored over Xmas at the motherinlaws, and have a play on the laptop.

[dinamik2t]

Wob, could you tell us the fuel type and compression ratio used along those tests? I think there must be some relevance to spark performance effects and these two factors, isn't there?


I added a legend to your image for convenience.

[wobbly]

That engine was running Avgas at 15.8:1 with a bronze toroidal insert that could be rotated to index the plug.
It was modified later to over 50 Hp at 13000 and won 3 straight 125 kart titles.

[Grumph]

TeeZee's 1.2L Plenum ... 24mm carb 34mm inlet from the plenum to the crankcase ...

The old "suck it and see " method ? I've got Vizard's formulas here somewhere for 4 stroke inlets - it's not simple arriving at a working inlet resonator, then you adjust on the dyno....Should be simple enough to insert packing pieces to change the volume.

[husaberg]

Grumph sent me these pics

Also V4 2000cc two stroke
Ihad seen the end use but never wondered what powered it.
It could do with a Wobbly pipe or 4
http://twostrokemotocross.com/2009/0...stroke-engine/

I don't know where the V4 came from that you posted but here's the Martin Jet Pack power head.
Limited I believe to around 5500 rpm to obtain sufficient life for certification to fly.
Four CR500's and ChCh built.

The engine is indeed the one and the same.

[Kickaha]

Grumph sent me these pics
I don't know where the V4 came from that you posted but here's the Martin Jet Pack power head.
Limited I believe to around 5500 rpm to obtain sufficient life for certification to fly.
Four CR500's and ChCh built.

The engine is indeed the one and the same.

Saw the bare crankcases in some blokes garage one day , I wondered what they were for

[Grumph]

Saw the bare crankcases in some blokes garage one day , I wondered what they were for

I'll bet you immediately asked if you could have one for the outfit....

[TZ350]

I was looking through some links posted by Husaberg and came across this one of a performance Kart engine and was very impressed by the finning on the crankcase, it sort of suggests that case cooling should be taken seriously.

[husaberg]

I'll bet you immediately asked if you could have one for the outfit....

Which outfit? with an outfit like theses and with peanut tanks like those, Kickaha hardly needs to accessorize. Sorry Warwick beer made me do it?

[koba]

I was looking through some links posted by Husanburg and came across this one of a performance Kart engine and was very impressed by the finning on the crankcase, it sort of suggests that case cooling should be taken seriously.

That reminds me of something I meant to bring up ages ago.

Have you seen the crank-case on the old Steve Roberts Aluminium Monocoque bike?

It has had a tool (Looks like a bluntened drill bit maybe) run all over it to increase the surface area.
I'll see if I can find a pic. Someone else may post one too.

May be a good trick to try on a bucket.
I dunno how much of a difference it would make. There has to be a small weight saving too.
Maybe not worth the time and effort but only one way to find out really.
I'm not sure there would be as much lee-way with meat in the cases as an old GS1000 motor though.
It would also be important not to pick up heat from the pipe (as Frits points out).

[husaberg]

That reminds me of something I meant to bring up ages ago.

Have you seen the crank-case on the old Steve Roberts Aluminium Monocoque bike?

It has had a tool (Looks like a bluntened drill bit maybe) run all over it to increase the surface area.
I'll see if I can find a pic. Someone else may post one too.

May be a good trick to try on a bucket.
I dunno how much of a difference it would make. There has to be a small weight saving too.
Maybe not worth the time and effort but only one way to find out really.
I'm not sure there would be as much lee-way with meat in the cases as an old GS1000 motor though.
It would also be important not to pick up heat from the pipe (as Frits points out).

I think what you have seen is what is called dimple drilling
It was big in the 60's commonly done on the inside of already light things like crankcase covers it would provide a small weight (and i mean small)saving on a sandcast Triumph chain-case but it would do little on a diecast cover and probably weaken them (Crack etc)

What about encasing the crankcase in paraffin Wax this absorbs an incredible amount of heat to change state from soild to liquid and again from liquid to gas.
http://autospeed.com/cms/title_The-F...2/article.html

The obvious advantage over water/ice is it turns back to solid all by itself.

I think it has some merit in regards to crankcase cooling note there are other less common wax's that have higher melting points.


If its good enough for NASA (I would avoid their o rings though)


http://ntrs.nasa.gov/archive/nasa/ca...2010043777.pdf
http://ntrs.nasa.gov/archive/nasa/ca...2011009592.pdf
Thermal Mass

The limiting factor in such a 'closed-loop' heatsink intercooler design is the amount of heat it can absorb. In the small water/air core being used in the Mira Turbo, the thermal mass (the amount of heat able to be absorbed for a given temperature rise) was sufficient for all but the duration of boost used on long hills. And that was with only a few litres of water (and the copper tubes) for the heat storage.
Water has a very high thermal mass, or more technically, a high specific heat. Think of it like this: when you place a saucepan of water on the stove it takes the input of a lot of energy before the temperature of the water changes much. (Try heating that saucepan of water with a single candle!) In fact the specific heat of water is 4.18 kilojoules per kilogram per degree C. So, to raise the temp of 1 litre of water (1 litre of water has a mass of 1kg) by one degree C requires 4.18 kilojoules of energy. As I said, that's a lot.
In fact, as a comparison, have a look at some specific heat values of common materials:

Material	Specific Heat (kJ/kg/degree C)
Water	4.18
Aluminium	0.94
Copper	0.39
Air	1.01
Concrete	0.88

So if you were using a solid block of aluminium as your heat storage mechanism, you'd need 4.4 times the mass of aluminium to get the same heat storage as water. (As you can see, specific heat doesn't have much to do with how good a conductor the material is.)
If you want to make a heatsink that's capable of absorbing lots of heat without increasing much in temperature, you could use lots of water. For example, if the heat of the boosted intake air could be conducted to - say - 20 litres of water, I'd bet that in a road car the intake air temp on boost would never get very high. But 20 litres of water is 20kg, and because water is a poor conductor of heat, you'd also need a really good heat exchange mechanism.
Hmmm, too big and heavy.
So is there a commonly available substance with a much higher specific heat than water? The short answer is 'no'.
Doing it Differently

These sorts of questions are also being covered extensively in an industry that has nothing to do with turbocharged cars. In solar house design, adding thermal mass is important because it knocks off the highs and lows of temperature extremes that are experienced by the occupants. For example, because water has a much higher specific heat than say concrete (see table above), some designers place storage containers of water within the house. This water gradually rises in temp on the hot days (keeping the house cooler) then feeds the heat back out as the temperature drops (keeping it warmer). In short, the water containers act as heatsinks, knocking off the peaks and troughs in the temp variations.
But the same problems apply to using large bodies of water in a house as they do to a turbo engine heatsink/intercooler application-lots of water is needed if you want to absorb lots of heat. So solar house designers are exploring a completely different way of storing that heat.
They are now using materials that absorb a lot of energy as they change in state.
Huh? That's it? Yes - now let's look at what that means. It is incredibly significant.
We've covered the idea that materials have a specific heat - the property of the material that determines how much heat it can absorb for a given temperature increase. But there's also another characteristic of materials, called the specific heat of fusion.

Let's have a detailed example. We'll start with a solid (rather than a liquid or a gas) which we'll call 'Performal'. We get a chunk of Performal and put it in a saucepan on the stove. We then place a thermometer probe in the Performal and turn the stove to 'high'. Every minute we take a temp reading, and as expected, the stuff starts getting warmer. It must have a pretty high specific heat, because even though the stove is set to high it warms up only slowly. In fact, the graph here shows the temp increase that we measured over the first ten minutes.


We're getting pretty bored with this experiment (what is this, a performance car magazine or a science class?!) and so when we jot down '50 degrees C' as the temp after 10 minutes we're thinking more of that night's cruise than anything else. And so when the next reading after another minute is also 50 degrees C, we get the uncomfortable feeling that we've stuffed up the readings. The stove is still running on high, pouring heat into the Performal, but a further minute later the temp of the Performal is still 50 degrees C!What the hell is going on? Have the laws of physics and chemistry gone out the window? We're continuing to add heat - lots of it - but the substance isn't getting any hotter!?
What is happening is that the Performal is melting - it is changing from a solid to a liquid at 50 degrees. And when it undergoes that change in state, it can absorb lots of energy without altering in temperature. Instead of heating the material up, the energy from the stove is being used to separate the material's molecular bonds.
Until all of the Performal has changed from a solid to a liquid, its temperature will not change. That's what the above graph shows - and you can see that the temp is being held constant, even though we're continuing to pour in the heat energy from the stove. It's only when the Performal has completely melted that its temp will start to rise again - and then the rate of temp increase will be dependent on the specific heat of Performal in liquid form, which might be different to its specific heat in solid form.

So here's a graph that showed what happened as we heated the Performal. When it started to change state, it had the capability of absorbing a huge amount of energy without getting any hotter. And the amount of energy it can absorb during this change of state is called its specific heat of fusion.

Some Definitions Specific Heat - the quantity of heat required to raise the temperature of one gram of a substance by one degree Celsius. Specific Heat of Fusion - the quantity of heat required to convert a substance from the solid to the liquid state with no temperature change. Melting point - the temperature at which the substance changes from a solid to a liquid.

Back to Cars

So where does this leave us? Well, let's pack a conventional air/air intercooler core with Performal. We'll first heat the Performal up until it melts, then pour it through all the fins of the intercooler, filling them right up. After that, we'll place a water-tight jacket all round the core (so the Performal can't leak out when it melts) and then we'll insulate the assembly so that under-bonnet heat can't affect it. Finally, the new heatsink will be installed in the turbo-to-intake plumbing.
Remember, Performal has four different characteristics that interest us:

• Its specific heat as a solid
• Its melting point
• Its specific heat of fusion
• Its specific heat as a liquid

To remind you, Performal's melting point is 50 degrees C.
So, the car's cold and so you only gently drive it down the street on this 30-degree C day. But after half an hour of this gentle driving the temps have stabilised: at idle the temp of the air coming out of the turbo is 40 degrees C, and the temp of the Performal heatsink is also 40 degrees.
Then you put your foot down. The turbo spools up to 15 psi boost and the air coming out of the turbo rockets from 40 degrees to 80 degrees. But a lot of this heat is absorbed as the air passes through the aluminium and Performal honeycomb heatsink, so the intake air temp at the engine remains much cooler - say (with some heat exchange efficiency losses) it's 50 degrees C. After 5 seconds of full boost the heatsink has risen in temp to 45 degrees C, with the heat all being absorbed by the Performal's specific heat capability as a solid.
You get back off the throttle and go back to a cruise. The heat from the heatsink is now fed back into the airstream, which is now cooler than the heatsink. Effectively, the heatsink is being internally cooled.
But that five seconds of boost has whetted your appetite: this time you wind it right out through the first three gears at full boost. The temp of the heatsink rises: soon it has reached 50 degrees C and the Performal starts to change state, to melt. Its ability to absorb energy without rising higher in temp is now taking effect: despite a huge amount of heat being pumped into the heatsink, the outlet air temp stays just the same, at (say) a constant 55 degrees C. Again, when you get off the throttle and the air flowing through the heatsink is lower in temp than heatsink temp, the heat will be fed back into the intake airstream and the heatsink will cool. As it cools the Performal will start to solidify, until when it has all turned back into a solid, its temp will start to drop below 50.
The speed bug has bitten and you decide to go for a top speed run: on full boost continuously for a minute. The Performal then warms up, reaches melting point and holds the intake air temp steady. But it can only do this while the material is melting, and after 40 seconds it has all turned to a liquid. At this point, its temp will again start to rise, but even as a liquid it will be absorbing heat and so reducing the turbo outlet temp. Of course, when the police catch you and you are having a roadside discussion, that heat will be being fed back into the airstream: it is likely to stay warm for some time.

Ice/Water Fusion Intercooler Drag racers who use a mixture of ice and water in a heat exchanger core are already using a fusion intercooler. The specific heat of fusion for ice (ie how much energy per kilogram is required to melt it) is 334 kJ/Kg. That's why ice/water systems are so effective - a lot of energy is required to melt the ice and the ice/water mix will stay at 0 degrees C until all of the ice is melted. Trouble is for a road car, the water doesn't turn back into ice when the car's back off boost.....

The Potential

You can see now why some 2700 words ago I said that for the system to be effective, the off-boost intake air temp must be below 50 degrees. Otherwise, with the normal off-boost heat the Performal would be melted all of the time, and so its capability to absorb heat during its change of state would be gone. (That is, it would already be changed in state!)
That off-boost turbo outlet temp will be dependent on a number of things:

• The temp of the air being breathed by the turbo
• The heating of the compressor side of the turbo by the exhaust manifold and turbine
• The size and design of the turbo
• The temperature of the day
• The airflow through the engine bay

In areas of cold climate the off-boost turbo outlet temp is very unlikely to ever exceed 50 degrees C, however, when the ambient is 40 degrees C the air coming out of the turbo will often be above 50 even when off-boost.

I had intended fitting a Performal heatsink to my Nissan Maxima VG20DE turbo, however the transverse engine location (the turbo is heated by the radiator airflow), the very small turbo and the long intake path all conspired to give a turbo outlet temp of about 30 degrees above ambient! Since where I live the ambient seldom drops below 20, the Performal would be frequently already changed in state, even before boost hit. It's therefore not suitable for this car and climate, and it shows how important direct measurement of the actual temps really is.
(Of course, I could place a free-flowing but very small air/air intercooler in front of the Performal heatsink - this would cool the off-boost air sufficiently to keep the Performal as a solid, while the small air/air intercooler's performance on boost wouldn't matter - it would just need to flow enough air to not be a restriction. However, space constraints mean that such an approach on my car would be very difficult.)
"Performal"?


The potential on the right car is huge: but what actually is bloody "Performal"? Time to let you into a secret - and some of you may have already guessed. "Performal" doesn't exist but a substance with very similar characteristics is commonly available. It is called paraffin wax, and is sold for use in making candles. Specifically, its typical characteristics are:

• Melting point: 52 degrees C
• Specific heat: 3.27 kJ per kg per degree C
• Specific heat of fusion: 210 kJ/kg

So to increase the temp of 1kg of the wax from 47 to 52 degrees takes 16.35kJ, but to push it past 52 degrees takes nearly 13 times as much energy. (Or, to risk causing confusion, you could dissipate in it a power of 14kW for 15 seconds to melt 1kg.)
Paraffin wax is non-toxic, doesn't explode (although it will catch fire if you expose it to a naked flame) and is easily handled. Special waxes designed specifically for this change-of-state heat storage purpose are also available with melting points in 10-degree C increments from 50 degrees to 100 degrees C, however their availability is obviously less than simple candle wax.

Constructing One? The easiest approach to making a fusion intercooler would be to obtain a small air/air intercooler core, which has adequate airflow for the application. The core could be sealed with sheet aluminium welded into place, much as the water/air design shown here was constructed. The assembly could then be heated to perhaps 60 degrees C in an oven and before having its core completely filled with molten wax - but with a small gap left for expansion. The resulting assembly would then need to be insulated from underbonnet heat, perhaps by being placed in a larger box and having the gaps filled with expanding foam applied with a spray can.

From Here?

As I said above, the car that I had hoped to apply the technology to isn't suitable: its off-boost intake air temp is too high. However, in the past I have owned turbo cars where the off-boost intake air temp was only 5-10 degrees above ambient, and these would be suitable for the technique. Remember, this approach would not be appropriate for race cars or for cars spending long times on boost on a dyno; it would however be very suitable for turbo cars where packaging is very tight (or a rear- or mid-mounted engine is used) and where in normal road use the duration of boost is limited.
It's a fascinating concept, which as the URLs below show is now being used in other industries and applications. (To find more links do a web search under 'phase change materials heat storage' or similar.) Equipped with a wax or other phase change material that melted at (say) 65 degrees C, the fusion intercooler could even be used as a 'safety' heatsink, able to knock the top of peaks that only rarely occur, or occur for only a very short period.
Either as a main intercooler/heatsink, or as an additional safety device, it's certainly something with huge real-world potential.

[TZ350]

EngMod2T

Port STA's ... (Specific-Time-Area's)

Working out the size of the ports and port duration or timing needed for the rpm and power output I want.



Choose the peak power rpm then target power output.

In the Edit-Engine-Screen click on the Target BMEP Calculate Button and you use the pop-up screen to enter the Target Power in kW or hP and it calculates the BMEP required in Bar.



After entering the port dimensions in the Edit-Exhaust-Port, Edit-Transfer-Port, Edit-Inlet-Port and other basic info I can check and adjust the ports untill they achieve the STA's required.



Pretty easy way of getting a development plan on target quickly .... or exploring whats possible with what I have.