ESE's works engine tuner

[Flettner]

No - assumptions - they are just errors waiting to be revealed.
I already told you , if you treat each Exhaust port as a single ( to BDC ), then make the exit of each, 90% of that ports chordal area x Cosine of the roof down angle.
No guessing , no assumptions , proven methodology.

There is no definition between above transfer open and below transfer open port area.

[wobbly]

The area above TPO is called Blowdown , that plus the area below TPO to BDC is the Total Effective Exhaust Area.

[Flettner]

The area above TPO is called Blowdown , that plus the area below TPO to BDC is the Total Effective Exhaust Area.

The more blowdown effective area you have, the less area under transfer open to keep a correct Total Effective Area in 'balance' ?

[wobbly]

Wrong - you are making the assumption that the Total Effective has a major influence on the end result.
It is absolutely the least effective metric of anything.
Blowdown and Transfer STA in balance , are the be all and end all of an effective porting layout.
Sure, it by default impacts the duct exit area if using the 75% area guideline , but it still works very effectively in all situations.
The absolute correct methodology is to measure the duct exit Mach, but this can only ever gain a few extra % in power when starting from the 75% area rule for a 3 or T port layout.

[Flettner]

Wrong - you are making the assumption that the Total Effective has a major influence on the end result.
It is absolutely the least effective metric of anything.
Blowdown and Transfer STA in balance , are the be all and end all of an effective porting layout.
Sure, it by default impacts the duct exit area if using the 75% area guideline , but it still works very effectively in all situations.
The absolute correct methodology is to measure the duct exit Mach, but this can only ever gain a few extra % in power when starting from the 75% area rule for a 3 or T port layout.

I have photos to try to explain what I'm thinking but for some reason I've ben shut out from posting photos??
Not sure if its my phone or this site? Anyway what I will do is carry on but use the single port, 90% calculation for each side as we discussed and see what happens I guess.
I don't mean to be a nuisance, it just happens

[husaberg]

I have photos to try to explain what I'm thinking but for some reason I've ben shut out from posting photos??
Not sure if its my phone or this site? Anyway what I will do is carry on but use the single port, 90% calculation for each side as we discussed and see what happens I guess.
I don't mean to be a nuisance, it just happens

Photos atm are hard to attach, I think there is some software issues, I have to click and hold button in for a few seconds then let go and that seems to help.
I thought it was me and I signed up to another forum the other day and its not my mouse of internet. Its KB.

[F5 Dave]

Ie been having issues with photos too.

[rgvbaz]

Hi all,

I'm after the ring pin location on a single ring kx100 piston - I can't seem to find it anywhere.

The standard two ring pin positions are available at Grampions site: https://www.mitaka.co.uk/piston.php?id=40
And are at 11 and 19mm from the centre.
I've brought one of there pistons and the top ring (at 19mm) is close to the B port and ideally I'd like to widen that a little.

Failing that, if anyone know of a 52ish mm piston with a 14mm piston pin could you point me in that direction.


The reason is that my Kawasaki AR93 barrel has cracked at the bottom of the liner (thats really thin with the current 54.5mm bore size) so a new liner, slightly smaller piston dia giving more thickness to the bottom of the liner coupled with a 10mm longer rod I have found may help prevent cracking. And fingers crossed give a little more power.

Cheers

Dave

[aljaxon]

Hi all,

I'm after the ring pin location on a single ring kx100 piston - I can't seem to find it anywhere.

The standard two ring pin positions are available at Grampions site: https://www.mitaka.co.uk/piston.php?id=40
And are at 11 and 19mm from the centre.
I've brought one of there pistons and the top ring (at 19mm) is close to the B port and ideally I'd like to widen that a little.

Failing that, if anyone know of a 52ish mm piston with a 14mm piston pin could you point me in that direction.


The reason is that my Kawasaki AR93 barrel has cracked at the bottom of the liner (thats really thin with the current 54.5mm bore size) so a new liner, slightly smaller piston dia giving more thickness to the bottom of the liner coupled with a 10mm longer rod I have found may help prevent cracking. And fingers crossed give a little more power.

Cheers

Dave

ive had a few problems with pins being in the wrong place. im currently running one with the gap over the middle of a transfer on one project, forget which. im sure they can be moved to suit. i shy away from tasks like that thinking they have to be done by specialists but i bet its just a case of pillar drill a bit of heat and possibly some space age glue and lots of crossing your fingers and toes. is it cos the aluminium expands quicker and more than the steel so the pin never comes loose?
in theory.....

[aljaxon]

quick question, what is the most likely reason that changes to tailpipe/baffle cone outlet diameter are making a massive difference to power output in my project in engmod yet hardly any difference on my pals different slightly smaller cc project? from 17 to 15mm on mine it makes a huge difference. his are almost identical. only when he goes down to 12mm does it make a big difference and then he gets like a growth on the top of his curve. looks weird.

[Frits Overmars]

the aluminium expands quicker and more than the steel so the pin never comes loose?

Think again....

[husaberg]

Hi all,

I'm after the ring pin location on a single ring kx100 piston - I can't seem to find it anywhere.

The standard two ring pin positions are available at Grampions site: https://www.mitaka.co.uk/piston.php?id=40
And are at 11 and 19mm from the centre.
I've brought one of there pistons and the top ring (at 19mm) is close to the B port and ideally I'd like to widen that a little.

Failing that, if anyone know of a 52ish mm piston with a 14mm piston pin could you point me in that direction.


The reason is that my Kawasaki AR93 barrel has cracked at the bottom of the liner (thats really thin with the current 54.5mm bore size) so a new liner, slightly smaller piston dia giving more thickness to the bottom of the liner coupled with a 10mm longer rod I have found may help prevent cracking. And fingers crossed give a little more power.

Cheers

Dave

The 100cc conversions for rm and cr and ktm are 14mm 52mm
strike does 52mm 14mm pin pistons for kt100's
http://www.strikeproducts.com.au/pistons.asp
http://www.strikeproducts.com.au/pricelist.asp

[aljaxon]

Think again....

this expansion thing has always messed with my head. lets say a small hole in some aluminium, as you heat it up the aluminium expands and so why doesnt it expand towards the hole making it smaller?

why does the aluminium expand away from the hole and not towards it. i mean it expands towards the outside. how does it know which way it can expand?

[wobbly]

Forgetting for the moment about expansion - ring pins are easy to do.
You use drills , and or drill blanks if you can buy them.
Many are 1.5mm so you buy one at 1.45 to drill the hole , and a 1.5 to cut off the pin needed.
I grind an " arrow" head on the pin, as this helps it to enter the hole , and the alloy closes in around the reverse sharp edge and helps to hold it in place.
Some pins are in the upper face of the groove, not on the groove centerline - so you push a piece of alloy into the groove and make a center pop, then drill the hole and remove the inserted piece.

[wobbly]

Re stinger size effects. Its all to do with the bmep, and thus the flow rate at peak power.
The simple way to get a handle on this is to set the Exhaust Transducer length at 1/2 the stinger nozzle , and look at the Mach number at peak power rpm.
It should be 0.8 Mach.
Higher and the stinger is too small , lower its too big - easy.