ESE's works engine tuner

[peewee]

frits your a great help but i dont understand your 8.1% corner radius. i only know radiuses in mm.

tz350 what is a damn ? is it just a term for filling in the exh floor like me and wobbly are doing ?

[F5 Dave]

I am defiantly going to include in my next motor.

The word " Definitely" may be a better choice to use in this phrase ??

You may wish to be careful on a single ex port engine. As Frits says if the blowdown is not sufficient the pressure will abuse the transfers as make shift exhaust ports. This will still happen but if you seriously raised the port floor to the transfer level it would be worse. But that's an extreme case of course.

[Grumph]

I am defiantly going to include in my next motor.

The word " Definitely" may be a better choice to use in this phrase ??

Well, i've met both you and Rob. Defiantly works for either of you...Didn't you tell me you had enough Benelli barrels to keep you happy playing for years ?
tried doing a triple exhaust in one yet ?

[TZ350]

well, i've met both you and rob. Defiantly works for either of you...

................. true, well I hope so anyway.

[TZ350]

tz350 what is a dam? is it just a term for filling in the exh floor like me and wobbly are doing ?

I am not sure what the proper name is or even if there is one but I called it a dam because it seems to work by reducing short circuiting from the transfers and damming the flow of incoming fresh air/fuel charge preventing it looping over and easily flowing out of the exhaust port. Just like a dam on a river.

[Frits Overmars]

i dont understand your 8.1% corner radius. i only know radiuses in mm.

It's 8.1% of the cylinder bore, like all the other percentages in that drawing.

[husaberg]

Jan raised the Aprilia port floor at the duct entry 2mm ( on a 54.5 stroke ) above BDC I believe, and the bottom corner rads were
made progressively bigger and bigger to reduce the duct volume.
This is dyno proven ( his and mine ) to make better power, so go there straight away, but as you say dont reduce the blowdown width
of the main port above TRO.
Testing the reduced duct area at the port, and reducing/varying the area at the duct exit is easily optimized in EngMod, except of course as its not a 3D FEA flow code
like Fluent etc it cant verify the effect on power of reducing short circuiting.

Jan tested everything and 25* was best.

RSA ex port
The exhaust port isn't canted downward 30°. The flange mounting face is canted downward 30° but the roof of the exhaust duct exits the cylinder at 25°.
The reason is that this angle gives the best flow. Frits I think?

The cylinder I have also has its exhaust port above bdc by about 2mm.
But I would suggest the bottom of the exhaust port has a distinct curvature near the outlet.

[Frits Overmars]

RSA ex port: The exhaust port isn't canted downward 30°. The flange mounting face is canted downward 30° but the roof of the exhaust duct exits the cylinder at 25°.
The reason is that this angle gives the best flow.
Frits I think?

Guilty, your Honour.

[husaberg]

Guilty, your Honour.

ok any ideas what this cylinder is it was in my Aprilia pics but it doesn't look in place.

[Frits Overmars]

ok any ideas what this cylinder is it was in my Aprilia pics but it doesn't look in place.

Provisions for coolant hose pillars left and right; could be a kart cylinder (they all copied Aprilia).

[mudbugracer]

I would like to give the good old Suzuki TF125 engine a wake up, can anyone give info about port measurements? also need to use factory carb so any idea on jet sizes after the port work? Or any other idea to wake her up?

[ken seeber]

Report from northern hemisphere.

[FastFred]

I would like to give the good old Suzuki TF125 engine a wake up, can anyone give info about port measurements? also need to use factory carb so any idea on jet sizes after the port work? Or any other idea to wake her up?

This whole thread is about giving 2T engines a wake up.



And your best friend will be a degree wheel like this one made by gluing a paper printout onto piece of sheet metal another easy way is to buy a large protractor from a stationary shop.

[mr bucketracer]

I would like to give the good old Suzuki TF125 engine a wake up, can anyone give info about port measurements? also need to use factory carb so any idea on jet sizes after the port work? Or any other idea to wake her up?

sorry they only put things to sleep in here lol

[Flettner]

Report from northern hemisphere.

Ha Ha ha. What, didn't they like you telling them we know what was inside?
A little wind up never hurt.