ESE's works engine tuner

[jamathi]

Having all 3 of the Ex ports closed by a PV in effect reduces the blowdown to virtually nil.
This works OK in a MX situation, where the engine is used well off the pipe and the low PV setting reduces the really bad effect of the pipe being way to short for the rpm.
In a roadrace engine the combination of the open Aux port with the PV down in the main port, allows a usable amount of blowdown at the lower end of the powerband.
Then the PV is lifted over a fairly wide band of rpm, giving a much wider powerband ,in the range that is used on track.
The Aprilia, and many other engines using this setup,they dont have the PV all up until about 1000 rpm before peak power.

Yes Wobbly, exactly!
By the way, did you already test the ceramic coated exhaust duct?
And what was the result?
Is there any news about TM's 'uncooled' exhaust duct?

Regards, Jan

[Grumph]

I dont recall a single protest in Chch buckets in the last 15 years, that doesnt mean there is no reason for them as i have seen plenty of evidence that not everyone plays by the rules, the score is still zero

Levels has a nice big scrutineering shed....how do you feel about stripping the first three in the BoB ?

Back in the 90's we stripped the whole field of 250 production - with some amusing results....

[Yow Ling]

Levels has a nice big scrutineering shed....how do you feel about stripping the first three in the BoB ?

Back in the 90's we stripped the whole field of 250 production - with some amusing results....

Wouldnt worry me, but then Im not entering this year. Up to Cams to do what they want. Wouldnt hurt, bit expensive for the FXRs to reassemble

[F5 Dave]

My MB wouldn't raise many eyebrows except for the triple exhaust port and rather conservative timings,. But full story would take more than a strip down.

[wobbly]

Hi Jan, I have been flat out building test pipes for TM, as well as doing the record breaking 350cc Pre 81 Land Speed Project at Bonneville.
Thus I have not been able to remove the test cylinder from the dyno to get it coated.
Franco is way too secretive to tell me I think, if his non cooled duct was a failure or not.
But i will ask, as soon I have a result to show him - wont be long.
I had originally been obsessed with getting over 50 Hp along with plenty of overev power, but the 30mm carb seems to prevent any real
extra peak power.One pipe made 49.6 and had 6 more at 14500, but on track that was barely faster.
So I have been hard at work trying to get more front side power, ie going up to the peak.
Here is where I am at now, and building/dynoing this pipe today.

[Nath88]

the 30mm carb seems to prevent any real extra peak power

If the carb is restricting airflow, could you use an additional volume in the intake after the carb to reduce the peak velocity through the carb but increase the average velocity?
Maybe a helmholtz resonator tuned to the peak, with a valve so it doesn't affect the rest of the range.

[F5 Dave]

Rob
We'll the TF inlet is a mess anyway with piston port and then a big hole in the floor for the reed.

I needed to fill in the manifold I'm using so made up this taper. It's hardly a shallow taper but will do as a stopgap and maybe be the 2nd trailing part of venturi.

[SwePatrick]

First stumbeling tests with turbo.
Fueling issues.
Need to revert to gasoline i guess.
If idling for a long time, i figure the fuel(methanol) drops out of airstream and then when hitting throttle the engines takes a big gulp.
One can fix this with heating the inlet manifold, but heck,, the engine isn´t warm yet, nothing to heat it up with(coolant water)
Leaning out the jet don´t work, yes it runs nicer, for a while... but after some revving the engine runs out of control and need bigger jet to idle at lower rpm´s.
Gasoline doesn´t have this issues, well a little but not this big.
However, in posted video i got it to run(not letting it idle) and it made 0.4bar boost(5.9psi) just holding the throttle(end of video)
I later leaned it out a bit and got a whole 1bar boost(14.7psi)
But i never got response from idle good.
I´ll switch to gasoline for a test.
I can use methanol for cooling later on if needed(meth/water injection).
I dunno if you can hear it, in the end when boost hits it revs up a little bit more(12800rpm).
Before that the pipe 'keeps' it on ~12000rpm

Rgds

[mr bucketracer]

First stumbeling tests with turbo.
Fueling issues.
Need to revert to gasoline i guess.
If idling for a long time, i figure the fuel(methanol) drops out of airstream and then when hitting throttle the engines takes a big gulp.
One can fix this with heating the inlet manifold, but heck,, the engine isn´t warm yet, nothing to heat it up with(coolant water)
Leaning out the jet don´t work, yes it runs nicer, for a while... but after some revving the engine runs out of control and need bigger jet to idle at lower rpm´s.
Gasoline doesn´t have this issues, well a little but not this big.
However, in posted video i got it to run(not letting it idle) and it made 0.4bar boost(5.9psi) just holding the throttle(end of video)
I later leaned it out a bit and got a whole 1bar boost(14.7psi)
But i never got response from idle good.
I´ll switch to gasoline for a test.
I can use methanol for cooling later on if needed(meth/water injection).
I dunno if you can hear it, in the end when boost hits it revs up a little bit more(12800rpm).
Before that the pipe 'keeps' it on ~12000rpm

Rgds

is the engine fuel injected?

[TZ350]

I needed to fill in the manifold I'm using so made up this taper. It's hardly a shallow taper but will do as a stopgap and maybe be the 2nd trailing part of venturi.

That looks the business......

[SwePatrick]

is the engine fuel injected?

No, simple Mikuni VM44 as it is in video.
But with added powerjet and 'ufo' plate.
And high flow floatvalve.

Rgds

[wobbly]

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.

[monkeyfumi]

What material are you printing in for petrol resistance Wobbly?

[wobbly]

The best material I have found so far is ABS,that has then been vapor blasted to seal the surface.Cheap to.
But i have a Nylon one coming to try as well.
This is fine for testing, but if I was to use it long term then I believe the simplest way would be to spray paint the surface with a 2 pot epoxy
like automotive clearcoat - havnt looked into it in detail yet.

[OopsClunkThud]

I've found Nylon holds up quite well around the carb, been playing with 3D printed bells on Vespas for some time.