Two-stroke performance tuning?

**F5 Dave** · 21st July 2009, 09:22

I'd take the 5th B.R. See if you can Winston around without answering the question. That's the SS way.

Change this thread to Political Mimicry.

**SS90** · 21st July 2009, 09:27

Originally Posted by Fooman

From my favourite reference for this sort of shitflinging (Bosch Automotive Handbook 3rd Ed - note translated from German, so ignore any verbal niceties)

Supercharging Processes (See attached .pdf file)

Summary - The expansion chamber is not a mechanical supercharger, but it provides a dynamic supercharging effect similar to the tuned intake tube charging effect described in the attached document.

From memory, dynamic supercharging (e.g. using inertia of incoming air into cylinder) gives a max of 105% to 110% volumetric efficiency.

I certainly hope this contributes to the thread!

Cheers,
FM

In an effort to get some clear information written before the local fools start replying, I have not managed to read your attachment as yet, but how abou this.

Do you know of any material (preferably not web based) that can accurately quote the VE of a performance two stroke?

I maintain that a performance two stroke IS MOST CERTAINLY NOT "SUPERCHARGED".

For the sake of "science" I will agree that you COULD consider there is a slight "SUPERCHARGE" "EFFECT" from an expansion chamber, however, that alone (the effect) does NOT constitute a "supercharged" engine, anymore that an airbox does.

Essentially, an expansion chamber pushes "HALF FUCKED" over heated low density air, fuel, and particle matter back in to the combustion chamber.

How does that constitute "a supercharged engine"?

**Skunk** · 21st July 2009, 09:27

Originally Posted by SS90

No it's not.

Sshhhhhhh Bucketracer....the grownups are talking!

You should shut up too then.

Originally Posted by SS90

OK, so tell us Bucketracer.......WHAT IS THE VOLUMETRIC EFFICIENCY OF A PERFORMANCE TWO STROKE ENGINE?

You're the 'expert' - why don't you tell us?

Originally Posted by SS90

Teezeetreefiddy "old boy", once again, you have managed to use 1000 words to over complicate things.

Scavenge patterns essentially stop the incoming fresh charge from heading out the open exhaust port.

Unlike you who uses 1000 words to say nothing.

By the way - this may be a surprise to you - scavenging isn't perfect otherwise the 'chamber' would be a 'megaphone'. Well, no it wouldn't... There would be no need for anything because scavenging would do it all.

And I still haven't heard an answer on scroll diodes.

Back to school SS90.

**Skunk** · 21st July 2009, 09:31

Originally Posted by SS90

How does that constitute "a supercharged engine"?

By increasing the volume of air (and fuel in this case) in the combustion chamber, fool. I suggest you do some reading.

**SS90** · 21st July 2009, 09:33

Originally Posted by Skunk

So instead of telling me it's all dated and wrong how about telling me the modern and correct way.

Or is it so secret (because of the Asians) that no one is allowed to know?

I would LIKE to skunk, but I am worried that if I did, given the fact that Teezeetreefiddys engine (apparently) is "overheating" and requires dubious cooling efficiency improvements, (at a "wopping" 15.5 P.S) if I was to tell him how to make more power, it may well cause a Nuclear Holcaust of biblical proportions as it headed down the back straight, causing widespread destruction,and global warming of unprecedented proportions.

I don't want that on my head.

Mind you, he probably still wont win a race.

**Skunk** · 21st July 2009, 09:34

Originally Posted by SS90

I would LIKE to skunk, but I am worried that if I did, given the fact that Teezeetreefiddys engine (apparently) is "overheating" and requires dubious cooling efficiency improvements, (at a "wopping" 15.5 P.S) if I was to tell him how to make more power, it may well cause a Nuclear Holcaust of biblical proportions as it headed down the back straight, causing widespread destruction,and global warming of unprecedented proportions.

I don't want that on my head.

Mind you, he probably still wont win a race.

Then it's pointless you posting here. Goodbye.

**SS90** · 21st July 2009, 09:35

Originally Posted by Skunk

You should shut up too then.

And I still haven't heard an answer on scroll diodes.

Back to school SS90.

SCROLL DIODES!!!!!!!!!!

Bahahahahhahahaha!

Ask Thomas.......it was his "idea" wasn't it?

**SS90** · 21st July 2009, 09:36

Originally Posted by Skunk

By increasing the volume of air (and fuel in this case) in the combustion chamber, fool. I suggest you do some reading.

Got any proof of that?

**Skunk** · 21st July 2009, 09:39

Originally Posted by SS90

SCROLL DIODES!!!!!!!!!!

Bahahahahhahahaha!

Ask Thomas.......it was his "idea" wasn't it?

Still no answer though.

Got anymore informationless criticism?

**Skunk** · 21st July 2009, 09:40

Originally Posted by SS90

Got any proof of that?

Got any proof that every text available on chambers is wrong? That's right - you can't say.

**SS90** · 21st July 2009, 09:40

Originally Posted by Skunk

Still no answer though.

Got anymore informationless criticism?

Come on Skunk.... who's idea was it, yours or Thomas's......???????

**SS90** · 21st July 2009, 09:42

Originally Posted by Skunk

Got any proof that every text available on chambers is wrong? That's right - you can't say.

Bhahahahahhaha!

INTERNET BASED TEXT?????

bwhwhwhahahhahah!

Your complete inability to accept new information is why SOME of you fail to accept that it is possible to make a 125cc air cooled ingine (4 speed) with 30 PS.......