ESE's works engine tuner

[nitro2tfx]

The whole return wave is displaced in time, thus can be calculated to be shown graphically with the correct relationship to the crank sensor.
Still cant believe the intellectual Hp that completely missed that basic physics.

Not sure who would have missed that ?

There are quite a number of waves happening, particularly in a bad pipe design, and it takes surprisingly little in the way of adjustments to a pipe to go from good to bad, sometimes just the fabrication process itself.

I am hoping Neels is still on here and uses the one engine speed exhaust/intake pressure trace that I posted, along with the engine details to gravitate to the right bit of input tweaks in his software, creating a similar graph to the recorded one, then go from there in the discussion using different engine speeds.

[Muhr]

Thanks you reply,

In 3d printing what is the duration over time?

How much is the shore hardness?

I would certainly not say that I am an expert on flexible filaments but there are very many brands. Then there are also several different writing methods such as extrusion (FDM), SLS, SLA.
flexible filament made by the manufactur that make the printer I use I think is at 60 in shore.
which may not be optimal for what you want to do.

below an attempt to simulate the dellorto rubber I intend to use for the 50cc engine I am building

[wobbly]

Neels code has the functionality already to show exactly the same graphical data as you have posted.
Here is the closest I have to a Banshee 350, this is Henise's TZ350 with reed conversion that holds the LSR for non streamliner on petrol at Boneville @ 170.519 mph
showing Exhaust and intake pressure ratio @ 8000 rpm.
Can you expand the X scale to show only 360* total ( ie one cycle ) centered on BDC , as this is probably the most critical area of pipe design we need to be looking at.
Plus add the case pressure ratio as well , on the same graph , as this enables optimum tuning of a reed engines intake length.

[ken seeber]

A question of logic:

Old mate over here in the land of Oz is doing a 35 cc RC engine, essentially with a scaled down RSA KZ cylinder format, using a 38 mm piston.

What piston to bore clearance?

A Ø54 KZ runs around 0.07 clearance with a coolant temp of say 45 deg C. Using this as a guide, and scaling, this would be 0.07 *38/54 = 0.049. Now, the RC engine will be drawing in lake/sea water at say 20 deg. Assuming the piston remains at the same temp, but the plated aluminium bore runs 45-20 = 25 deg cooler. This would mean it expands less, to the tune of 38*25*0.000024 = 0.028.

So, a suggested clearance would be 0.049 + 0.028 = 0.077 = 0.003 inches

Sounds a lot, maybe wrong on the assumption that the piston remains at the same temp as a KZ, however note that these things run for either 8 or 12 min heats, full throttle for 100%, no cooling periods as for gear changing and backing off for a corner. Not to dissimilar to speedway karting where a 54 piston in an aircooled engine might have its clearance increased to 0.13 from 0.07 for a sprint kart circuit.

[Vannik]

I am hoping Neels is still on here and uses the one engine speed exhaust/intake pressure trace that I posted, along with the engine details to gravitate to the right bit of input tweaks in his software, creating a similar graph to the recorded one, then go from there in the discussion using different engine speeds.

Clint,

I am still here, a few times a day!

I do not have a Banshee model, if someone has one or a port map I can create one and run a few sims.

Neels

[nitro2tfx]

Clint,

I am still here, a few times a day!

I do not have a Banshee model, if someone has one or a port map I can create one and run a few sims.

Neels

Hi Neels, sounds good. I don't have a port map in hand at the moment as porting is something that will be done later on, so ports haven't even been looked at yet. Yes I know porting is more often done first than last lol, as it is a no-brainer, but the goal for this Banshee is probably a whole lot different from other people's Banshee projects.

[nitro2tfx]

Neels code has the functionality already to show exactly the same graphical data as you have posted.
Here is the closest I have to a Banshee 350, this is Henise's TZ350 with reed conversion that holds the LSR for non streamliner on petrol at Boneville @ 170.519 mph
showing Exhaust and intake pressure ratio @ 8000 rpm.
Can you expand the X scale to show only 360* total ( ie one cycle ) centered on BDC , as this is probably the most critical area of pipe design we need to be looking at.
Plus add the case pressure ratio as well , on the same graph , as this enables optimum tuning of a reed engines intake length.

The "functionality already to show exactly the same graphical data as you have posted" is a stretch, but yes Neels software is a useful tool too, and in the past Neels and I had discussed using both technologies together to create something even better than apart.

Do you know any more details about the TZ350 you posted i.e. power at 8000, and what was peak power rpm, custom exhaust presumably, custom porting ? etc.

I can change the scaling as requested, but as a point of interest seeing what happens on 2 consecutive cycles in one graph also has it's benefits, not always, but when there is something different happening between one cycle and the next, then it is a big plus.

There is no crankcase pressure recorded on this engine as yet, waiting on a sensor. The case ratio is stock. Everything about the engine itself is stock except for the heads, it's all just bolt-ons for the moment, including the heads.

[philou]

I sell my kidneys to have access to this technology?

[nitro2tfx]

I sell my kidneys to have access to this technology?

Are they in good working order .....or........lol.

[wobbly]

Nitro , why do you say the exact same functionality is a stretch ? I can use the sim output data to super accurately predict the performance of every single change to an input element.
Be it a 1mm change in header length , to 1* change in ignition timing.
And to boot it has outputs for every concievable performance indicator , that you would need another 20 sensors to log.
The x axis scaling I mentioned simply due to you commenting that pipe design analysis was a point of interest .
In this regard all we need to see happens between EPO and EPC ie centered on BDC , what the pipe/port pressure ratio is doing when its closed is pretty much irrelevant - thus stretching this scale gives much better insight.

I have microscopic data for the TZ350 LSR engine as it was completely designed in EngMod . Starting with a 250G cylinder and a 58mm Banshee crank the pipe , ignition , squish , compression ,reed thickness ,intake length ,duct areas/mach , everything was optimized with probably a Kg of alloy Tig rod.
And its a testament to Neels code that every single element was built as designed on screen , it went to the salt having only been started from cold , did a few runs to get the Lectrons dialled in -
then smashed the LSR record out of the park.
Have a look on Jeff Henise FB page , all the mods done are there in detail - https://www.facebook.com/jhenise/pos...55500252306228

[Condyn]

I have said it before and I will say it again. That project inspired the hell out of me. I am unable to view most of the photos because I refuse to be on Facebook, but the basis of my current snowmobile engine masterpiece (in the making) if you will, was derived from the Henise, Wobbly project. My crank is out getting stroked square at the moment, and then the joy of doing aluminum sleeves for the first time. Details and Questions to follow.

[dutchpower]

Neels code has the functionality already to show exactly the same graphical data as you have posted.
Here is the closest I have to a Banshee 350, this is Henise's TZ350 with reed conversion that holds the LSR for non streamliner on petrol at Boneville @ 170.519 mph
showing Exhaust and intake pressure ratio @ 8000 rpm.
Can you expand the X scale to show only 360* total ( ie one cycle ) centered on BDC , as this is probably the most critical area of pipe design we need to be looking at.
Plus add the case pressure ratio as well , on the same graph , as this enables optimum tuning of a reed engines intake length.

Wobb do you have that showing ratio by 12000 rpm

[wobbly]

Yep Dutch , here is the same sim output @ 11,000 ( peak power ) and 12,000 peak rpm.
During the record run it would not change out of 5th gear into 6th , thus was pulling 12,000 thru the timing lights.
So there is still alot left on the table speed wise , and power wise once I get a chance to dyno the thing.
If there is a LSR run in the new year we are shooting for a 200mph medal.

[jfn2]

Hello Wobbly
Sims look very textbook. I have a question about one area. On both the sims at EPO there is a dive in case pressure. If I remember correctly Neels (at one time) mentioned this area should be higher with a pipe change. I don't remember what that change was. If it was higher it would heighten the peak pressure.
Also could you explain more about what a good reed stuffer should look like? I have a picture of a TM reed stuffer and I can not tell the difference from the pics between that one and the bad one just posted. Or am I just in need of more sleep? Thank you. Jeff

[wobbly]

The waveform , at a chosen rpm spread to suit the end use , should have the maximum possible residual pressure ratio at EPO.
This creates superposition of that pressure with that above the piston @ EPO , thus a higher amplitude pressure ratio travels down the diffuser creating a bigger depression around BDC.

The amount of residual pressure ratio is dependant upon the interaction of the port frequency and the Lt of the pipe.
This effect has a naturally bigger amplitude over a wider rpm range when the port duration is down near 190* , but of course this has a huge effect on the blowdown capability.
In the TZ350 I wanted a bias toward peak and overev power , so blowdown was far more important.
The really important elements of the pipes waveform is how deep and wide the negative pressure is around BDC , and the peak return waves position in relation to EPC.

I posted a pic of my best reed stuffer , that has a convex shape down the sides , the bad shape is concave blending to nothing at the tips.
Here is the printed TM stuffer I use again.