We have spent a
substantial amount of time and effort trying to quantify
real world power gains on naturally aspirated RMKs.
Driven largely by a genuine need to find a desirable
compromise to boost, its been a somewhat frustrating
Many kits we tested did indeed produce results, some
with impressive gains in throttle response and midrange
punch but fell flat on the big end, others just making
noise, however when weighed against the dollar
investment, most left us feeling slighted...
Though I have no question some of these indeed perform
well at other altitudes as advertised, they just didn't
show well with our use demand and altitude.
Various configurations of porting, heads, pipes,
silencers, pistons (even cat pistons), clutching,
timing, fuels and fuel controls have all been rendered
down to one true stand out.
Though I can only speak to our test results, which are
all done at 9500'-13000', the RKTek Drop in kit is with
a doubt the best bang for the buck...
Our testing showed the 13 kit produced impressive gains
in loose snow track speed, as well as significantly
better throttle response and power across the spectrum.
Though this package does require a fuel control (13
model), it is very easy to tune, it is also very easy to
clutch, and is rock solid consistent.
We will be doing follow up testing with different
exhausts applied to this kit soon (preliminary testing
shows great promise), and also a real world evaluation
of the RKTek big bore for the RMK 800 as well.
Seldom does such a reasonable investment produce such a
Just thought it worthy of mention as many of you have
inquired about such kits...
Eric Woog VOHK Performance Kremmling CO
purchased and installed one of your drop in kits for the
Polaris 800 dragon. I know you haven’t done testing on
the 2009 Dragon but I’ve been testing it and have found
it to be very rewarding. The cooling is at least 15 to
20 degrees cooler than it used to run and I needed to
install one step hotter plug. The throttle response is
amazing. It develops power way sooner than before and
holds torque all the way through to top shift at about
8150 or 8200 RPM. I am thrilled with the performance
and couldn’t be happier with your product. A friend of
mine who owns a 2013 Pro rode on it and couldn’t believe
it “Spanked” his sled. He liked the way it pulls hard
all the way from about 6000 RPM or so. I am
recommending your product to all my 800 Polaris rider
friends. Mitch Hartley Nampa Idaho
Good Morning Kelsey
Your heads are a definitive
plus and a advantage for my application and team.
Starting at 131 hp with
Mod spec for this season, it is very difficult to go
over 136 corrected hp on our
Changing timing configuration, bored
race fuel recipes and/or tune pipes does not add any hp.
We feel it is top there.
Adding your heads, is
another story. On my 2 Mod sleds, we finished w 140hp
and 144hp on the second one. Every legal modifications
we work with shows a result and improvements. Sounds is
way different and healthy, combustion and spark plugs
Response of the power on the track is a big plus too.
This weekend in
I had the fastest sleds from far!
have roughly 50 miles
on my 2013 155 pro with kelsey's drop in kit with the
higher compression head. I have "stacked" his set up
with an slp pipe can power commander and my own
clutching (not slp's set up). It is a noticeable
difference. as far as track speed i do not know yet as
we only have about 2 feet of snow right now. what i do
know for fact is that with this set up running the slp
stage 4 map which is def. on the rich side i was able to
quite easilly beat a 2012 stage 4 slp pro 800 in a short
drag race. not only that i am pulling 2 grams heavier
weights than the same set up with out the drop in kit.
and i'm pretty sure i'm going to have to add even more
weight. the power band feels much SMOOTHER and it even
gives the motor a lot crisper sound. I am sold on these
kits so far after a little bit of experience around
kelsey's product last year and this year. Lets just say
that mine ran good enough not even broke in that i have
already sold 7 more of kelseys drop in kits. Eric Woog
(owner of VOHK) is also running these kits and he def.
knows what he is doing when it comes to making power on
Kelsey. Put my drop in kit in today, nice stuff. On this
sled also all the annoying vibrations and 3000rpm
are gone. Smooth. The stock pistons were 3 grams
different in weight. The
wossner's were a full 27 grams
lighter and exactly the same weight to the gram. The old
setup when idling the coolant temp would gradually climb
of course and continue to climb without hesitation. Your
head cools so efficiently that
could get the temp over 133F it would just sit there.
Even when brought up to 4500-5500 rpm the temp would
slowly climb to 140F. What an amazing difference. Can't
wait for good snow now. Turned the oil pump up one full
turn and running 91 octane on the non eth resistor. 1/2
of semi synth
oil in full tank fresh fuel. Anything else you think
should know bud shoot me a pm when you get a chance,
know your flat out. Have a good one man.
Kelsey just a line to let u know how my 860 is running
had it out for four days in the hills and it ran strong
clutching still a little off but could give an
ETEC a head
start and pass him before the top and could only get to
3/4 throttle this thing just don't stop pulling thanks
for all your help and good work
Just finished redoing
the top end and used your dual ring pistons and very
nice anodized head. The shape of the dome compared
to stock is fantastic and there is no wonder why
this set up would make more power and be more
efficient. What was BRP thinking when they designed
that head and a single ring piston? I had plenty of
blowby on my old pistons. With the new pieces
installed, it sounds great and has a snap to it, not
like before. I am in the process of doing a quick
break-in time on it but I can already feel the power
far exceeds what I had in the past. Thanks for the
great product and quick shipping!
Grande Prairie, Alberta
I just wanted to give you a mid season
update on my 700-800
is all i
have to say, you did your homework. It flat rips
missed a beat in 650 miles. All my buddies cant
figure out what to think when
blast by them. Im
totally impressed with your work, and you will
continue to have my business.
thought I'd give ya a little update on my sled. I have
an 08 800r with your 13.1 head, porting and ecm remap. I
just did a full rebuild crank and with brp pistons, had
a dealer credit on them so didn't cost me anything.
Running 8hole base and squish at 48 thou and 450 mains. I
was on the lake here today against a shr 840 with twin
dmax pipes and he tried all he could and I was
consistantly faster. I have more to gain as I was
consistantly seein 8400 on the digital so lil more
flyweight and I'll pick up some more. Just wanted to
give a little credit where credit is due. Thanks for the
solid and reliable HP. Jesse
and warm greetings from Finland!