ESE's works engine tuner

[wobbly]

EngMod works exactly the same way , you enter the bmep ( HP ) you want at a specific rpm , and it analyses what you actually have Vs what you want.
You then do a series of changes to the ports to try and match the desired result you have entered as a baseline..

[wobbly]

The pipe design shootout has started on the EngMod FB page for the Thai KR150 drag race engine. All the sim factors are explained, as well as the rules and the .pack file is available.
If you are a user , then get into it.
I have submitted my pipe , and have started on the engine build for dyno verification , once the competition is finalized.

https://www.facebook.com/groups/5510...56769229641538

[aljaxon]

. removed post

[aljaxon]

EngMod works exactly the same way , you enter the bmep ( HP ) you want at a specific rpm , and it analyses what you actually have Vs what you want.
You then do a series of changes to the ports to try and match the desired result you have entered as a baseline..

thats basically what im doing. as i up the bmep it shows my motor is out of breath at a lower rpm. by moving the bmep figure up or down i can see how my porting is coping or not coping and how it needs tweaking. i previously got the blowdown and transfer sta's mixed up. i told you before im an idiot. and then i posted i needed 0.3mm in height to get everything matched at my desired rpm.

thanks wobbly.

[aljaxon]

The pipe design shootout has started on the EngMod FB page for the Thai KR150 drag race engine. All the sim factors are explained, as well as the rules and the .pack file is available.
If you are a user , then get into it.
I have submitted my pipe , and have started on the engine build for dyno verification , once the competition is finalized.

https://www.facebook.com/groups/5510...56769229641538

has that kr150 got a real narrow powerband by any chance?

i have in the past been guilty of taking a pipe design and multiplying all the lengths by a percentage to get the tuned length to what i require so as to keep all the sections in proportion to each other. and ive also done the same with the diameters to get the start diameter the same as mine and so all the diameters are still in the same proportion. the only thing that changes is the angles whichj have to due to basic maths.
my pal has kindly entered a few of these in EngMod with good and interesting results but based on a very simple (similar to mine) motor and keeping that a constant.
i was just wondering if what im doing has any merit or do i need my exact engine set up. or for a hobbyist working out of a shed (whos posting on the wrong forum i admit) is that near enough for what i need? at the end of the day i will be making a pipe so i look at it like anything to help me narrow down its design is better than nothing.

i have previously trawled and searched this thread and saved all the photos of pipe designs (mostly yours lol) and mostly for the rs 125.

[aljaxon]

no , the software is for knowing how to make the ports based on what BMEP you are after at which rpm. not the other way round.

and only if you have accurate data you can make an educated guess.
if you don't have accurate data, it's like a hand-calculator. You know what you want the outcome to be but not how to get there. if you want the outcome to be 10500 (your desired rpm) you can enter 10 x 1050 and it will be correct. you can also enter 100 x 105 and it will be also correct. or 10000 + 500, or ....
the 2 missing numbers for the hand-calculator are BMEP and rpm and as shown above, you can enter very different values and still get "a correct answer". As long as you have 2 variables you can only make wild guesses. you need to get it down to 1 variable to make an educated guess. for example : know the rpm of max power, and than you can guess what BMEP and from that what HP to expect. But that rpm is dependant on your exhaust and you are going to change your exhaust, so even that rpm isn't accurate enough.

it comes down to one thing : trial and error, and if you start from the wrong side, you are going to make more error's. start from the correct side and get accurate data and you will get your answer much faster. but either way, you will have to find the correct answer yourself. People here have given you more than enough advise to get to the correct answer, it's up to you to aply it.

i have been entering my desired rpm. and then seeing if the ports work at that rpm? and by shuffling the bmep figure up or down i can see at what revs the sta's match and that is basically the optimum rpm?

[Frits Overmars]

i have in the past been guilty of taking a pipe design and multiplying all the lengths by a percentage to get the tuned length to what i require so as to keep all the sections in proportion to each other.

That's good, provided the original pipe design was good.

ive also done the same with the diameters to get the start diameter the same as mine

That would be good if your start diameter was good. Chances are that it's not.

i was just wondering if what im doing has any merit or do i need my exact engine set up. or for a hobbyist working out of a shed....
is that near enough for what i need?

Of course you need your exact engine setup. 'Near enough' doesn't cut it. If you do not provide exact input data, you will get rubbish output data, no matter how sophisticated the applied software is. (and don't blame the shed. You should see the places from which we sometimes have to work.)

anything to help me narrow down its design is better than nothing.

And then you question what you are being offered.

[aljaxon]

i know im asking lots of questions but i honestly dont know where else to ask them.

in mind i am thinking the first diffuser or the bit of the diffuser nearest the header influences high up the rev range. possibly past peak - overrev? so a tiny bit further away from that influences peak power rpm. and the very end of the baffle cone influences peak power rpm?
so if i simply make these two areas sharper angles and make the rest shallower i am utilising the energy available in the pipe at the rpm i desire. the sharper angles get the biggest lunch.... at the expense of power elsewhere which is what i want for my cvt type motor

ive just done a design with this shape plus with an extra long belly stealing length from the baffle cone and my pal is going to run it in engmod to see if the theory holds with his limited porting.
id love to see a pipe design somewhere aimed at cvt. ive tried searching on here and using google to no avail.

im guessing the modern scooter boys with their stage 6 stuff would benefit from a pipe designed around the narrow rpm so maybe i can "steal" some ideas from the pipes they use?

[wobbly]

The KR150 used in Thai drag racing is actually a 180cc as they must use the stock 59mm piston ( dumb as nothing good is available off the shelf ) but everything else is
open.
They run a CNC made 65.5 stroke ( +11mm ), and the cylinder has the Kawasaki KIPS system , where only the ( highest ) Auxiliary ports have a PV.
For the pipe shootout the Aux ports have been returned to the " normal " lower than the main duration and the KIPS system is disabled, as there is no option for this in EngMod and its what is done in reality.

The gearbox ratio's are not well spaced , and the engine is held at around 7000 rpm on the line , where they dump the clutch and go WOT.
Thus front side power has to be built into the pipe, as the PV is only partially effective , but it needs to have overev out to a lunatic 13500 ( 29m/s) to enable the shortest gear possible.
Not a narrow range port/pipe setup at all.

[husaberg]

The KR150 used in Thai drag racing is actually a 180cc as they must use the stock 59mm piston ( dumb as nothing good is available off the shelf ) but everything else is
open.
They run a CNC made 65.5 stroke ( +11mm ), and the cylinder has the Kawasaki KIPS system , where only the ( highest ) Auxiliary ports have a PV.
For the pipe shootout the Aux ports have been returned to the " normal " lower than the main duration and the KIPS system is disabled, as there is no option for this in EngMod and its what is done in reality.

The gearbox ratio's are not well spaced , and the engine is held at around 7000 rpm on the line , where they dump the clutch and go WOT.
Thus front side power has to be built into the pipe, as the PV is only partially effective , but it needs to have overev out to a lunatic 13500 ( 29m/s) to enable the shortest gear possible.
Not a narrow range port/pipe setup at all.

Do the rules define the std gear ratios?
The reason I ask is there are lots of stuff on the net for cr sets for all sorts of the weirdo Asian stuff...

[aljaxon]

And then you question what you are being offered.

lol i wasnt aware id been offered anything apart from you saying the FOS cant be tweaked re sharper baffle cone unless it gives less power, and wobbly suggested a sharper baffle cone can give more power at the detriment to over rev and peak which im happy with. and that there are multiple other asspects which can reduce power band width.

i got my kind pal to enter a modifictaion to a pipe in his engmod purely guessing which part of the diffuser to sharpen the angle, and to sharpen the last bit of the baffle cone and it DID produce a much narrower power band but also lost out at the top. the curve actually followed the front side almost identically which amazed me. we have been inputting pipes designed for tzr's and rs125 etc downsized to my start diameter and his which are 26mm and 27mm id. the port effective area is 620mmsq which is effective diameter of 28mm. the tract is 24.5mm long so it reduces from 28mm to 26mm over 24.5mm length. the bore is 50mm. the cylinder architecture is such that it has a big threaded nut that goes around the header to secure it in the cylinder. even with it machined so its thin as fook. (apologies for technical term) i can still only get 26mm id. the lengths i need to go to to get the pipes start diameter to be spot on are too lengthy. if it was a race bike with every fraction of hp targetted then maybe id do it. but there are many more priorities ie leaking roof needs fixing first.

according to FOS design i need a 29.3mm D1 but my 82cc is that low in tune single ex port only 68% of bore width and not maxed very cup cake shaped. , plus heavily over square 50mm x 41.8mm i reckon i could get away with calling it 70cc's then that brings D1 into my 26mm territory. i can feel frits frowning.

this is the kind of thing ive been doing to pipe designs ive stolen off this thread. . shortening and reducing by percentage to suit my new tuned length and start diameter. the angles of each section change from original which cannot be helped if you keep same percentage diameters.


i borrowed one pipe design and downsized it which gave a lovely wide mushroom head type power curve, perfectly symmetrical at the peak when run in engmod combined with a motor that was very basic in comparison to the intended pipe.
sadly exactly the opposite of what i currently want.

all i need is an example of a pipe thats ok with a cvt set up and i can adjust it to suit my needs. but i cant find one anywhere.

[wobbly]

The Thai guys make special 1st and 2nd gears for the drag bikes.
I will have the ratio numbers over the weekend to compare.

[wobbly]

KR150 has stock 1st = 10/27 , drag race for light weight has 10/24 or heavier = 10/25
Second is stock 17/29 with drag race special 17/28 available.

[Storbeck]

Does anybody know a decent cheap/free program for analyzing large data files?

I have a crude water brake dyno, collecting data using an Aem Evo 4. Raw data from load cell through amplifier into an analog input on the evo4 and then I also can log RPM, egt, cht.

The raw load cell data captures the variation thoughout a single stroke, information I don't need, but I need to log at a high rate to avoid aliasing in the torque data then I just do a rolling average in post processing.

The Aem software does not lend itself well to this sort of thing, so currently doing it in Excel....which is clunky.

I have plans to improve all of this in the longer term, but in the mean time I'm more interested in doing development on my engine than taking on a dyno control project, so I can make it work with Excel clumsily but if there is some other readily available software out there that can do a little bit of post processing and just conveniently plot graphs with good functionality to zoom in and out and look at sections of data that would make things a lot easier.

I'm dealing with CSV's with something like 400,000 lines.

[Noxin]

Can you please upload one of your files somewhere where we can take a look at it?
I'm working on my own dyno software right now, so maybe I can fix something.