ESE's works engine tuner

[peewee]

We ran 40% nitro in this engine. It definitely stopped as soon as the plug burned off. The ground strap was a little hard on the piston on the way out the exhaust. On 15% nitro it ran fine.

Lohring Miller

Attachment 332121

do you have any advice about using nitro in a 2t ? I have 1gal nitro and 5gal methanol so I can mix my own percentage. my tank fuel valve flows 1gal (3.7L) per minute which is plenty im sure. this weekend ill figure how much fuel is passing through the carb float valve. my plan is to start with a low mix like 10% or even 5% and get it running well then go alittle higher to 15 or so. maybe even 20 but I don't want to put the cart in front of the horse just yet.

anyways I been using #9 and #10 heat range plugs with straight methanol. would 10 be a good choice for what im doing or even colder ? typically I been just using standard electrode. im guessing this should do fine ? i haven't yet installed any instant fuel cut off valve incase it should run away but im hoping that doesn't happen

the other thing i was wondering is spark lead. is it best to start with a setting that worked well on petrol and advance it in small increments as needed ?

heres something interesting that i found in a article and i wonder how truthful it is. maybe you could comment on it ? thnx for any help

Remember that the air/fuel ratio (AFR) we commonly refer to is pounds of air to pounds of fuel: feathers to lead. Weight, not volume. The AFR for alcohol: ~5:1. The AFR for 100% nitro: ~1.3:1.

If you saw a graph of the specific gravity change of the fuel (weight) for 0 through 100% nitro and also the AFR required for 0-100%, the lines would cross at about 33%.

From 0% to 33%, the change in the specific gravity of the fuel rises quicker than the change in the required AFR. The fuel is getting heavier QUICKLY at low percentages so you get more pounds per minute for the same air flow. The required AFR is not much different than straight alcohol. You actually have to go leaner to hit the optimal AFR you need.

After 33%, the AFR is changing quicker than the density of the fuel - more fuel is required to make up the difference. If you calculated it all out for 15%, you will see you have to lean the mixture from the optimal alcohol jet. This is probably why many people who run 20% say they don't see much of a gain in performance. They are way way way too rich and cancelling much of the benefit.

[SwePatrick]

If deciding to run on nitro, start pig rich!
Up to 20% it behaves quite normal, almost like methanol alone.
But getting upwards in blend things happen.
And when it starts releasing it´s own oxygen things happen fast, really fast.

One could run an electric powervalve controlled by exhaustheat to get full benefit of nitro.
Running cold it won´t produce any power.
Running hot and lean will produce aluminiumcoating in pipe *lol*

Find that sweetspot when it starts burning wild and add fuel at that point.
Make the stinger bigger(more power more diam on stinger)

One could take fuel directly from fuel line if running electric powerjet, no need to interference with carbs own fuel.

[SwePatrick]

The problem with the 30mm carb on the KZ engine is that the inlet is as short as it possibly can be, and it is connected to a reed
that is capable of over 50 Hp.
Thus no room for any divergent duct.
The current setup has alot of area infill from the stuffer, keeping the area pretty constant right up to the petal curtain area.
I am trying all manner of test shapes using 3D printed inserts with various wings and guides,as the best power is had using very soft top petals
along with stiff lowers.
This biases the flow upward toward the transfer duct entries.

Even though they aren´t allowed in karting.
Have you been comparing classifeid reed against V-forve 3 in dyno?

Do V-force stand up to the task?

Rgds

[wobbly]

I have used a VeeForce 4 from a Banshee - more power everywhere,except very top end in a motor used in an open class with a 34mm carb from a Rotax Max..
But big issues with petal ends chipping.

[SwePatrick]

Nice.

And i got the same problems both with boyesen and v-force.
It slams the petals hard so they chip.
Best results with modded std kawasaki reed.

Thanks for info =)

[jamathi]

I have used a VeeForce 4 from a Banshee - more power everywhere,except very top end in a motor used in an open class with a 34mm carb from a Rotax Max..
But big issues with petal ends chipping.

Hi Wobbly, did you already hear about the Ryger's 'success' in Holland.
It was only 2.5 seconds a lap SLOWER than a TM......
On a track with a lap time of about 35 seconds.
Now they are celebrating.
Sales can start now......
Anyone?

[sb07]

Yes Jan, that is really quite some difference.

But what you don't seem to know from your reliable witness is:
that the Ryger was almost 2,5 sec quicker than the TM KZ10c special.

So the opposite of your very well known "reliable witness"

And it was driven on the track of Pottendijk at Emmen last sunday Sept 3th, 2017
So make your witness known, because someone likes to change the real story.

you insist?
stop ... ryger is slow ...
is a continuous... bla bla bla...
I'm on the track every week ...
Ryger is famous only on the internet, only on forums no one is fear!!!
On the track everyone is talking about TM, Modena, Vortex ... iron with cocones !!!

[SwePatrick]

Is there a misunderstanding here?
If someone beat me with almost 2.5s it means they have beaten me with almost 2.5s =)
like 2.4x seconds.

[lohring]

My experience with nitro in ignition engines was in a series of tests to prove that simply changing the fuel in our 26 cc race engines wouldn't significantly help the power. The picture was from a very brief test series where we tried glow ignition. Since the plugs didn't hold up we ran spark ignition with good results on lower nitro ratios. In both test series no attempt was made to optimize the compression, ignition, or pipe for the fuel. We ran the same setup as for gasoline except for the mixture.

As model glow ignition engine racers, we had methanol fuel with various nitro percentages between 15% and 60% and with 20% synthetic/castor oil. The tests in the series in the .pdf below ran 8 oz. of oil per gallon. As you can see there was very little difference when you allowed for the precision of our inertial dyno. All the graphs are an average of 3 identical runs.

Lohring Miller

[mitch meyer]

I have used a VeeForce 4 from a Banshee - more power everywhere,except very top end in a motor used in an open class with a 34mm carb from a Rotax Max..
But big issues with petal ends chipping.

I have had same problem with chipping on die cut reed petals. I coated the top edge and side edge of petals with West System epoxy and this cured most of the problem. 250cc methanol outboard at 13 to 14000 RPM. It might be worth a try.

[wobbly]

Yes Jan,the proof would have been that several Rygers would have been on track this week practicing for the
biggest KZ race of the year in Germany.
There are two NZ racers there,so I have follower the session times - not a Ryger on the board.

Re reed petal chipping,I have "fixed " this by carefully sanding the edges with 600 wet and dry,and putting a generous radius on the outer corners.
This works well in SKUSA CR125 as well as KZ class, but the hard plastic cage on the VeeForce is super critical on petal frequency, too soft and they shatter.
I will try the epoxy idea - is it a 2 pot you simply paint on ? maybe good for petrol protection of 3D printed plastic reed stuffer inserts as well.
Its not available here, could you PM me re getting some sent over to NZ.
cheers
Wob

[Lightbulb]

My experience with nitro in ignition engines was in a series of tests to prove that simply changing the fuel in our 26 cc race engines wouldn't significantly help the power. The picture was from a very brief test series where we tried glow ignition. Since the plugs didn't hold up we ran spark ignition with good results on lower nitro ratios. In both test series no attempt was made to optimize the compression, ignition, or pipe for the fuel. We ran the same setup as for gasoline except for the mixture.

As model glow ignition engine racers, we had methanol fuel with various nitro percentages between 15% and 60% and with 20% synthetic/castor oil. The tests in the series in the .pdf below ran 8 oz. of oil per gallon. As you can see there was very little difference when you allowed for the precision of our inertial dyno. All the graphs are an average of 3 identical runs.

Lohring Miller

Some years ago, we tried to make a full tuned pipe engine for model boats that was to use a fuel with a minimum of 50% nitromethane. The supplied test engine did not use a proper full pipe , while it did make really good power, we could get as much power with a full pipe and 10% nitro fuel on the supplied engine. I built one up to run the 50% nitro. When it was close to running right, produced too much heat and melted holes in the piston every time or collapsed the crown. These were glow engines. My conclusion was with the heat being generated that the piston was not capable of dissipating that energy to the liner walls. It was water cooled head only. The bottom of the case was cold, but the area around the transfer ports was warmer than normal. For the very short time that it ran, the power output was very substantial. It was increase in power in the order of 30% with the 50% fuel over the 10% fuel. If the engine only needed to run for less than 6 seconds it will be great like a scale drag race car. We just tested with propellers and the power increase in general is the 3 of the rpm change.

[husaberg]

Yes Jan, that is really quite some difference.

But what you don't seem to know from your reliable witness is:
that the Ryger was almost 2,5 sec quicker than the TM KZ10c special.

So the opposite of your very well known "reliable witness"

And it was driven on the track of Pottendijk at Emmen last sunday Sept 3th, 2017
So make your witness known, because someone likes to change the real story.

[jamathi]

I will not give you his name, but he was the most capable person present.
So you will know who I mean!
And please stop telling fairy tales....
LOOSING 2.5 seconds a lap on a 35seconds track is ridiculous, not just very bad....
No 70 HP, not even 66, but about 33-35!
Who will buy such a piece of shit?
Not even the scrapheap will be happy with them...

[husaberg]

I will not give you his name, but he was the most capable person present.
So you will know who I mean!
And please stop telling fairy tales....
LOOSING 2.5 seconds a lap on a 35seconds track is ridiculous, not just very bad....
No 70 HP, not even 66, but about 33-35!
Who will buy such a piece of shit?
Not even the scrapheap will be happy with them...

i think you replied to the wrong person Jan.
I agree totally though, hence the Trump reference.