ESE's works engine tuner

[TZ350]

Found this handy little site:- http://users.erols.com/srweiss/tableifc.htm



Fuel injector Data



From the table, at 80% duty cycle my IWP023 injector can support 23 crank hp and the IWP043 48hp.

More Numbers:-

13,000rpm
= 217 rps or rp1000ms
217 x 1.5ms latency = 325ms
80% duty cycle = 800ms
800ms-325ms=475ms
475ms/217rpms
= 2.18ms of fully open injection time per revolution
and
If the maximum opening + closing speed of an injector is 1.5ms, then 1.5ms = 666 Hz or 40,000 rpm. So my injectors should be able to easily open and close fast enough for 13,000rpm.

[Flettner]

It's that "jolly" ECU ! Abandon it and use a Link. I've got a spare one here for you to use. You will just need a new wiring loom.

[Flettner]

just go simple, 1 injector at the body good fuel mixing, well thats what i would do

Dosen't work, too indirect to the cylinder. You will get inconsistant fuel mixtures up to the cylinder, remember the fuel is being deposited as small pockets in the main air streem. How do you know that small pocket will end up in the cylinder accurately every cycle. There is a pumping crank case in the way ( not 100% pumping efficent at below 1/3 throttle ), some fuel stays behind, some fuel goes through to the cylinder. This is where most twostroke EFI setups are comming unstuck.
In fact thats what happens, combustion chamber "sees" rich / lean every few cycles.
Stick to your guns Rob, I'm just not too sure I trust that ECU.

[TZ350]

Rob, I'm just not too sure I trust that ECU.

Something is wrong, it just should not be this hard to get sorted.

[Flettner]

Something is wrong, it just should not be this hard to get sorted.

Your welcome to borrow my Link ECU, it's not in use at the moment.
Actually I've also got an Ignijet ECU as well, although I don't know anything about it yet, you could try it if you like.

[TZ350]

Thanks, but I am a glutton for punishment and want to try and conquer this thing.

[Flettner]

The offer is there, any time.

[mr bucketracer]

Dosen't work, too indirect to the cylinder. You will get inconsistant fuel mixtures up to the cylinder, remember the fuel is being deposited as small pockets in the main air streem. How do you know that small pocket will end up in the cylinder accurately every cycle. There is a pumping crank case in the way ( not 100% pumping efficent at below 1/3 throttle ), some fuel stays behind, some fuel goes through to the cylinder. This is where most twostroke EFI setups are comming unstuck.
In fact thats what happens, combustion chamber "sees" rich / lean every few cycles.
Stick to your guns Rob, I'm just not too sure I trust that ECU.

just going of a book i read in around 2000 with a kart engine with direct injection just had 1 injector on the head , seen it had no gearbox it would have to run good in its hole rev range, but maybe direct injection works diffient ...dont know

[TZ350]

The offer is there, any time.

Thanks, the offer is much appreciated.

... kart engine with direct injection just had 1 injector on the head , seen it had no gearbox it would have to run good in its hole rev range, but maybe direct injection works diffient ...

Slightly different process, compressed air is also used, possibly a peak and hold injector to, for fast opening. But like you say, it makes you think, why can't port injection be done with only one injector too. I will have a go.

[mr bucketracer]

Thanks, the offer is much appreciated.





Slightly different process, compressed air is also used. But like you say, it makes you think, why can't port injection be done with only one injector too. I will have a go.

think anything is worth a try , if it does not work .no lose and no gain as they say . have a good xmas

[TZ350]

think anything is worth a try , if it does not work .no lose and no gain as they say . have a good xmas

Thanks .... have a good Christmas too, if your off to Wanganui, have a great time and please post something about the racing and how Guy got on.

[F5 Dave]

It was good. He got about 5ths and mostly stayed on.

[TZ350]

Thanks, it will be interesting to hear more about peoples adventures when they get back, and more of Guys exploits.

[husaberg]

Slightly different process, compressed air is also used, possibly a peak and hold injector to, for fast opening. But like you say, it makes you think, why can't port injection be done with only one injector too. I will have a go.

Moto guzzi was using fuel injection with compressed air in the 50's
if i trip over it i will post it.

[mr bucketracer]

yip around 5ths guy got , one race he pulled in half way through the race ,my mate went over to see him and he was moaning about his airbox been wrong lol . nasty one with sloan frost and nick cole going under him in the (Esis)can't spell ) anyway sloan crashed and went under the airbag..took i think 4-5 mins before anyone pulled them up and got him out .. the spectators jump the fence in the end and lifted the bags of him lol ..looked nasty though