Replace
those cheap plastic fittings that are always breaking.Thunder Products Polaris Air Box Synchronization kits are made from billet
aluminum and brass.The
new fittings also have an equalizer line to connect the fittings and
synchronize your carburetors.This equalizes the pressure to each carburetor for a smoother
running engine. If you don't have this kit, your carbs are not
synchronized!
PF-2
Polaris Air Box Fitting - Twin
$19.95
PF-3
Polaris Air Box Fitting - Triple
$29.95
Air Box Balance Kit
The Air Box Balance Kit insures that each carburetor
float bowl sees exactly the same pressure drop signal from the air box.
This synchronizes the carburetors' fuel delivery, giving you a smooth
consistent running engine.
Why is a balance kit necessary? When we talk
about a balance kit we are referring to an application where the
carburetor float bowls are vented into the air box (more on this type of
venting later). Each air box is different in terms of size, shape,
air entry and number of carburetors it is servicing. One thing is
for sure. Each air box has a lot going on that doesn't meet the
eye. There is the constant pulsing from one cylinder drawing in
air after another. The air volume is tremendous. We have air
flow and turbulence not to mention the acoustic resonance. Add all
of this together and then try to imagine that each carburetor is seeing
the same signal without being equalized. Hard to imagine, isn't
it?
Any knowledgeable performance shop or tuner will
agree that synchronized carburetors are a must for performance.
Let's take carburetor tuning a step further and talk
about various ways that carburetors are vented. Some manufacturers
vent their carbs under the hood. This makes the carburetion system
vulnerable to under hood pressure. Here is what happens. The
faster you go, the more air is forced under your hood. This
creates a higher pressure in your float bowl which forces more fuel
through your fuel circuit making your engine run richer. In other
words, the faster you go, the richer it gets. This robs power from
your engine. Let's say you are riding your sled at 50mph into a
25mph headwind. This would raise the under hood pressure equal to
riding at 75mph without any headwind. You will be running very
rich at only 50mph. The point is that this makes your jetting very
inconsistent. When you are dealing with headwinds, tailwinds, or
no wind, all of these conditions produce different jetting results.
The next type of carb venting is called atmospheric.
The carburetor vent lines are run up the steering post and end up
outside of the hood, usually ending up near the handlebar pad. You
must make sure not to pinch the vent lines shut when securing them to
the steering post or exiting the hood or you will cause fuel starvation
and cause engine damage. Other circumstances that could cause
jetting variations with this venting method are atmospheric pressure
changes, snow or water or air blowing by the end of the vent hoses.
Now let's talk a little about venting carburetors
into the air box (Polaris vents their carbs this way). We believe
this is the best way due to the overall consistency. This method
also circumvents the problems outlined with the other methods,
especially the rich condition due to under hood pressure. The
negative pressure in the air box reduces fuel delivery in a predictable
manner and produces more power.
The Air Box Balance Kit is a direct bolt on to
Polaris models and no jet changes are necessary. We don't want to
forget to mention that we use heavy duty billet aluminum air barbs to
plumb into the air box. No more broken plastic barbs! The
change is easy, inexpensive and well worth your time.
THUNDER PRODUCTS,
INC.
21676 Deep Lake Road
Richmond, MN 56368
Phone - 320-597-2700
Fax - 320-597-2712
Regular business
hours: Mon 9am - 8pm, Tues through Fri 9am - 5pm, Sat 9am - 12:00pm CST
Technical questions can be
answered by telephone
only during
regular business hours.