FYI: RK TEK "DROP IN" PISTON AND HEAD KIT FOR PRO 800'S

[mountainhorse]

I talked with Kelsey for a bit on this yesterday.. got the scoop and thought I'd post this up for our readers.

RK TEK has a new piston and Cylinder head kit that is designed to help your 800 CFi in 2 ways
1) Improve power
2) Improve reliability of the engine.

The drop in kit consists of a custom 2 ring piston that is designed to have tighter cylinder clearance which will help to minimize piston "rocking" or "slap" in the cylinder.

The Piston also has a different dome height which will change the port timing... when used in conjunction with the billet head included in the kit, the compression ratio will remain optimal for the chamber design on pump gas.

The head has gone through many different versions to get one that worked well with the stock mapping and pipe.

The head is available as a full billet replacement head with domes (no "cheater head") ...available in silver, Black and orange anodize.

The pistons are custom made for RKTek...Forged...but in Kelseys words, the piston will have the same user friendly character as a factory cast pistons and no special warm up will be needed.

I installed the same type of pistons and head on a REV 800 summit last year... ran for 1400 miles... pulled the cyls to check them out.... just fine and went back together with the motor. No special treatment...In fact, a fair amount of abuse and neglect by the owner.

Kelsey said we could expect the same in the Polaris 800.

I was told that there is NO pipe or can change is necessary (in fact, RK found that, for his kit, the stock can worked the best) and no fuel controller or other engine changes.

He is working on a pipe design to further improve the performance character of the kit, but will only release one if it truly give a noticeable improvement.

More information, including pricing and other details can be found at:
http://www.2strokeheads.com/Polaris800DropIn.htm


Some pics of the kit.

Please... lets keep this thread on topic. This is not a place to bash on their products... nor talk about other competitors aftermarket offerings.. this is a "FYI" thread on this particular product.

If you want to speak about the virtues or have criticisms of this or of another mfg, please do so in another thread.

I will ask the same of the other brand FYI's I put up.
Thanks in advance













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[joshkoltes]

opt

Hope for an optional turbo head

 

[rmk727]

So are we purchasing it for engine reliability or is the power enhancement significant enough to justify the price?

 

[friscospices.com]

Now thats honest! What a stand up dude.

 

[Hairy Mark]

so to be specific. what kind of gains are to be expected and what is the cost of the kit? i only ask this because i know kelsey has already dynoed it and has some specific numbers that he can post.

 

[SLDHVN]

Is this more for the stock motor sleds or will it benefit turbo's as well?

 

[pura vida]

think he is marketing more towards the stock motors rather than the turbo guys. but would have to call and ask him to be sure.

$799 and didn't see what the actually hp torque increases were. just a claim of an increase.

pv

 

[TurboMatt]

What kind of compression ratio are we looking at?

 

[2XM3]

Just having the forged pistons would be nice...lol...heads a bonus !!

 

[RKT]

Eric,

Thanks for the thread...

The kit will work at ALL elevations because we design the head around the elevation and octane. So, no worries there.

Turbo??? Should wake a turbo up like no tomorrow.. but I have not tested it on the turbo.. But, knowing what I know , it should be a great match.

Kelsey

 

[mountainhorse]

Kelsey,is the drop in kit ready for sale?have you done low elevation testing on it?it is time for me to replace piston,but i dont want to go OEM due to the horrible clearance specs on these.are the drop in pistons cast or forged,are they tighter than OEM?

Yes, the drop in kits are ready to go...New Black or Orange (your choice) Billet heads come with the kit, along with a piston that will not fail and is clearance CORRECTLY for the bore dimension.

The current set up we have will allow for running today's ethanol fuel while using the NON Ethanol resistor.. Working very well.. No control box, aftermarket pipe, can, or other items required.. We designed this kit to run with todays bad fuel, stock components and still make some serious power..

For the $$$ spent you can not beat this set up..

Kelsey

Please tell me how you know this makes 15 horse without dynoing it Kelsey I have asked this two other times can you not answer the question?

Where did you see this +15hp??

Also try calling him, if your that concerned with it.

...

 

[diamonddave]

Kelsey, is this a modified Pro-X piston?

 

[mountainhorse]

Dave, custom pistions from scratch is what I was told by Kelsey.










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[joshkoltes]

test

ill test it on my turbo, send it on over ill let you know how it works

 

[BYOB]

Can we get a dyno sheet that shows the factory and rk setup from the same sled or at least a solid number as to what the gains are? Is there going to be a cheater head available in the future? Timeframe if so? What is the price?

 

[mountainhorse]

I doubt you'll see a dyno sheet from Kelsey (or Carls or HPS for that matter)

As I said above... RK Tek does not offer this as a Cheater head.

Click on the link for all the pricing etc questions.










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[RKT]

So are we purchasing it for engine reliability or is the power enhancement significant enough to justify the price?

BOTH!!

We have addressed, what we feel, are problem areas with the OEM piston with our piston design

THEN.. Add the patened head design and the increased airflow and you have a much "happier" engine!!

Very nice performance gain.. price is very low considering the gain in performance and the longer engine life..

860 is also working good!

 

[sledhead_24_7]

BOTH!!

We have addressed, what we feel, are problem areas with the OEM piston with our piston design

THEN.. Add the patened head design and the increased airflow and you have a much "happier" engine!!

Very nice performance gain.. price is very low considering the gain in performance and the longer engine life..

[COLOR="Yellow"]860 is also working good!

[/COLOR]

Now that is what I am wanting. If it is half as good as what my 09 xp 860 was then it should rip.

 

[v8lover]

HP gains from stock with this drop in kit, I know someone chirped about 15Hp, but better to hear from the builder. I'm tied between PA head kit, or RK Tek kit. I've heard awesome reviews about the PA kit, but the custom pistons is intriguing, but just wanting to get the best for the $$$.

 

[RKT]

HP gains from stock with this drop in kit, I know someone chirped about 15Hp, but better to hear from the builder. I'm tied between PA head kit, or RK Tek kit. I've heard awesome reviews about the PA kit, but the custom pistons is intriguing, but just wanting to get the best for the $$$.

Yes, some nice HP gains.. It has been compared to several
"other" aftermarket kits and has always came out on top..

I do not play the HP numbers game.. Dyno sheets can be made to display whatever one wishes..

The Truth is on the mountain.. If a guy is waving a 20HP gain dyno sheet and he gets highmarked by a "kit" that has no HP value attached to it.. which "kit" do you want to have in your sled?? The Highmark or the lowmark with the big dyno sheet??

Again, results on the mountain do NOT lie.. Reality is reality