Boost Bottle



Has any body tried a boost bottle on a whizzer 4 stroke,or do they only work on 2 stroke engines??? :rolleyes::rolleyes:
Bill b
2-stroke technology

Hi, well, the boost bottle is strictly to "pulse" back into the cylinder increasing the charge in the head, on a 2-stroke. It will have no logical effect on a 4-stroke engine.

performance concepts are in most cases completely different.

Boost Bottle de-mystified

Hi Fetor, I cannot completely understand why you would refer me, and the other 4-stroke Whizzer guys to 6 pages of back and forth 2-stroke chatter with very little scientific information.

If you had read this stuff, one thing came out in the first page that the boost bottle PROBABLY (read WON'T) work on a reed-valve engine.

When I had high interest in performance on the little chinese engines, I did some research on boost bottle technology, and here is the Reader's Digest Condensed version.

The total displacement of the boost bottle and it's lines and fittings, to be most efficient, should match EXACTLY the displacement of the engine. Ported into the intake, when the 2-stroke "sneezes" back into the carb, it would (presumably) "charge" the bottle with mixture, and upon intake, the contentents of the bottle would "push" a little, while being sucked back into the crankcase. This was thought to be a little like "supercharging" the crankcase. This system was credited to Yamaha Corp in the dissertations I read.

Ok, now if the reed (in between the engine and carb) would stop the action of the bottle, what do you think might happen with our intake valve? A good running 4-stroke will NEVER sneeze into the carb. We also do not charge our crankcases with mix to run, we port gas mix directly above the piston.

We concern ourselves with combustion chamber size and shape, cam profiles (lift and duration) carboration, cam and ignition timing, belt management, and other such issues.

In reality, there are very few simalarities in 2-strope and 4-stroke tuning and performance.

I hope what I've sadi here might clear up any confusion.

Mike, Thanks for your 2nd reply, What you said makes sence to me, I will look for free HP-performance in fine tuning other ares of the engine, ie cyl head,carb tuning,timing,cam. The possibility for performance gains in these engines is amazing. Well instead of turning my water bottle into a boost bottle, i think I;ll make a tool kit out of it. There's really no manifold to tap into anyway. Thanks for the info guys :D
Bill B
I was suggesting to billspirit that there have been a number of threads started previously about Boost Bottles and a search beforehand would have helped for getting background info.I've seen peoples comments on these threads(including yours i believe) about 2-strokes/4-strokes so i figured the more knowledge the better....sorry about the confusion.
Hi Fetor

Hi, now for me, that makes sense, even tho that technology does not work on any valved engines,

would a 9 ounce co2 bottle from a paintball gun make a good bottle for the kings 80cc (69cc) motor i don't know the math or how to figure it out
Boost bottle confusion

Dear Wayde, this is 4-stroke Whizzer area, but I will answer your question anyway just to be a good sport.

Basic math: above I stated that your displacement should be equal, correct?

If your 9oz bottle holds 9 LICQUID ounces, how many cc's would that be?

1 Liter = 1000cc's
1 quart=16 us ounces
one US quart=946cc's
one 9oz bottle=473 cc's

473cc's + volume inside the lines and fittings do NOT equzl 69cc's?

Well the Hose must be 1/2" if hes getting 17+CC"s out of it I get 4.29 on my PVC SET UP With 9 1/2" of 3/16" W/O even minusing the 1.35cc for the King nipple Disp. 17CC That is well over what I got for a hose Measurement

Note: CID = No. of Cylinders(1) x 0.7854 x bore x bore x stroke (all in inches)
CID to CC"s Conversion multiplier is 16.3870641
Reason being there is 16.3870641 CC"s in 1 CID
Intake BackPressure Canister for Continuous Flow:

2ea.: 1/8" npt King nipples
9-1/2 " of 3/16" gas line
5-3/16" of 1" schedule 40 PVC pipe glued, capped (both ends)! one end tapped for 1/8" king nipple (another for Manifold)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
69.71cc theorium and solution

TUBING : 3/16"=.1875"

.7854 X .1875 X .1875 x 9.5"(1/2"=.5") = 0.262311328125 CID = 4.298512548141 CC"s

Engine Displacement of Mine is 69.71CC - 4.29851254814cc (9.5" of 3/16" Tubing Displacement) =
/side note 66.0802038 Left for (Cylinder/Booster can) Displacement/

Plus the Booster can being 1"x 5.1875" (5-3/16") = 4.0742625 = 66.7652007477 CC's

(Hose Disp. + Cyl Disp.)4.298512548141 CC"s + 66.7652 CC's = 71.063712548141 CC"s

Now to take out the 1/8" King Nipples inserted into the Manifold and the Canister/Cylinder and Hose

1/2=.5 .5+.5 =1" and bore size cut in half on 3/16" tubing is .09375"

.7854 x .09375" x .09375" x 1" of length = 0.0824203125 Cid= 1.350625 CCs"

Clndr+Hose Displ - Fitng Dspl. = Exchangable Backpressure Volume Displacement in CC"s is 69.7130875 CC"s
71.00637125481cc - 1.3506269cc = 69.713087 CC's

There it is the Print out for you build a PVC Intake Backpressure/Booster/Normalizing Canister

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