ESE's works engine tuner

[kel]

that depends so much on alot of info we still havnt seen yet ( such as the PWM curve for the powerjets etc),then its a case of crap in = crap out.

speaking of which - from the discussion on the pitlane GP125 all you wanted to know thread, it seems possible Aprilia did not switch off the power jet for over rev as the honda did (well maybe?)

Jan Thiel
"A very important thing when accelerating is the power you have after changing gear.
Spark interruption may be not so good for this!
As I did not have the dyno I wanted this gearchange effect could not be tried on the dyno, very regrettably!
Retarding the ignition and weakening the mixture by powerjet can also have a negative effect on this.
The exhaust temperature should be 'Right' for the No. of revs after you change gear.
If the temperature is too high there will be less power!"

On a seperate thread Frits shows the aprilia 100% throttle ignition curve which has noticeably more advance than the Honda at higher revs.

Lot of factors come into play obviously but Im wondering if this is the nature of the Triple port vs the Honda twin port and if its something TZ should consider for his GP125 triple port cylinder i.e. not turning off power jet and more advance in the upper revs at full throttle?

[Haufen]

I am thinking about building a new exhaust pipe.

If I have to make a, say, 180 degrees turn in routing the pipe, and leaving installation spacing issues aside, would it be better to make a large and smooth turn for about 3/4 of the pipe or would it be better to have the pipe make two smaller turns, allowing for longer straight sections in the pipe?

Is there anyone having any experience on this subject?

[wobbly]

The Aprilia had issues with the full throttle shift when in overev,if the engine was tuned correctly for max power and rpm with the powerjet,it would not " slow down " when the ignition cut was
initiated by the riders foot on the shift lever.
The powerjet was used as such in the overev, but I have not seen an ignition curve or powerjet % table to be able to make judgement on what was happening.
A powerjet used with an ON/OFF solenoid can recover a huge amount of lost rpm due to the carb becoming naturally progressively richer past peak power, but PWM controll is able to tailor the fuel delivery
to exactly what is needed for any effect.

I have never had the need to try huge bends in a pipe,Honda have done a U bend in several places on various pipes, but that was the only way to find room, and I doubt they could do
anything about any loss in performance.

[F5 Dave]

. . .
Lot of factors come into play obviously but Im wondering if this is the nature of the Triple port vs the Honda twin port and if its something TZ should consider for his GP125 triple port cylinder i.e. not turning off power jet and more advance in the upper revs at full throttle?

Another factor is use of unleaded race gas vs what we run may make comparisons inconclusive.

[kel]

Another factor is use of unleaded race gas vs what we run may make comparisons inconclusive.

avgas likes more advance so if anything I would guess the effect would be compounded?

[TZ350]

NedKelly and Chambers are having a crack at a F5 50cc stroker.

[F5 Dave]

Good, make sure you all enter the F5 GP next year (if there is a GP arranged).

[F5 Dave]

Good, make sure you all enter the F5 GP next year (if there is a GP arranged).

AM6 I guess.

[SwePatrick]

Pictures and or videos or it never happened. Seriously mate I am interested in seeing some of your work especially the Audi and Opel stuff you mentioned.

Just a little vid then
http://contour.com/stories/general-l...dtest-with-gps

Look at the yellow line to the bottom right in browser.
214.2Mph in an old non aerodynamic Audi 80 quattro from 1984, no wings no nothing to make it slice the air.
Just power, but that day on 'low boost'.
He also ran 9.37 with slipping clutch on 1/4mile.
http://www.youtube.com/watch?v=Ma5Nx...ature=youtu.be
Could be an high 8 when clutch can handle the power, never been done thou, so it hasn´t been done.
this car makes about 1000hp at 3.5bar absolute pressure(350kpa)
The 1132hp engine is in Norway, no pics or vids on that car.

this was my own car until recently, no racevids but pics.

day before i sold it:

just a idling video of car:
https://www.facebook.com/photo.php?v=450826304474

I can´t sit and look for hours on internet on old sites just to locate all the dynosheets etc etc.
Those above links a only a few.

and a small vid of me revving my 'nopower honda MB5'
https://www.facebook.com/photo.php?v=10151044778469475
Of course there is NO power gain at all above 8600rpm, all i got is 21,34hp at that rpm, no more.
All else is just a big hoax, i thought everybody understood that..

Yours sincereley
Patrick

[SwePatrick]

what measurement tools are you using for the port flow

Stephen

Actually nothing.. the dyno in the end of enginebuild(or track)
when building,,, well,, i calculate the areas only.
then give it the design i feel should work,, And up to this point,, all of them has worked quite well in dyno or track


Rgds
Patrick

[SwePatrick]

And, wobbly..
I have done alomst the same thing to an lawnmower.
This is my biggest failure.. hehe.

It revved so hard i had to lawn grass to keep engine at lower rpm and full throttle, but i just had it going for about 5minutes.
then it seized and spit out the rod.. *lol*

Rgds
Patrick

[speedpro]

It must be common to hot up lawnmowers. My one was an old iron horse 2-stroke. I drilled out the transfer ports, removed the throttle after it broke, and ran it on 100 octane and acetone and castor oil. Smelt good but you had to mow the lawn fast to stop it overrevving too much.

[Gigglebutton]

I have a Suzuki 2 stroke mower that I have ported, recut the head and fitted a pod filter to. It will only start with Easy Start sprayed in the pod. If you mow in the rain, the pod sucks in water and runs ruff. When its not raining it has loads more grunt & revs a little higher & sound great. I just took it in to work to fix the air filter housing. Thought about making a pipe for it but thats a black art.

[TZ350]

Ok I have been playing with my lawnmower too, its hard to see in the pictures but I have radiused the edges of the exhaust port. Originally it opened 81 deg ATDC, now its radiused up to 78.5 ATDC.

Looking from the top the bottom edge of the exhaust port looks square, but when you look from the bottom you can see the curved shape of the port better.

The width between the cylinder and transfer where the glue is, is 13mm, it was 16 before, but Kel suggested it might be to much. Before I made these changes the 3ex cylinder made an easy 29hp at the wheel, hopefully I will get it onto the dyno soon to see what effect these changes have had, fingers crossed that they will be positive.

[ief]

Is it just the pic or did you 'miss out' on the opportunity to make a nice radius on the inner side (devcon) of the transfer? (seems wide at the bottom so can't see it getting far more wider inside the transfer?)