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Injector relocate

tdbaugha

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Not trying to derail your thread here Tony, but Axys Mtntk kits do work quite well with the injectors moved.

Also, on the note of pipe pressure to boost pressure ratio. Mtntk runs mostly around 1/2psi more pipe than boost. That's until the pipe lights up and they actually see higher boost pressure than exhaust pressure. Stock pipe, 3" muffler.
 

TRS

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Tory,
I'll be back on this project as soon as the Doc lets me back in the shop. Dyno time.
It definitely isn't a derail, I think it proves my thoughts and pipe pressure findings.
 
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tdbaugha

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Care to share what those findings were?

For reference, turbine inducer, exducers:

2860: 54mm, 47mm
2871: 54mm, 47mm
3071: 60mm, 55mm

EFR 6258(Mtntk) : 58mm, 51mm. But also consider that the EFR turbos have a larger diameter base at the wheel. So this inducer/exducer looks huge on paper but it is actually a bit tighter in reality.
 
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geo

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Looking good Tony. You make this look so easy. Any pics of your "Shop"? Tool room equipment, or CNC, or 'have a friend".
Press fit on the injector housings? What's holding the throttle bodies in, center stud? Did you keep the oil pump?

I know this won't be 29 bucks but if you are just piggy backing with the Vipec I hope you give us the final parts list and settings when your done. Looks "affordable" for the ol' Pro.
 

B&M Fabrications

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Mtntek relocates the injectors on their turbo kits for the axys. I asked at a snow show this fall about swapping the firing order of the 2, If I remember correctly they said they did not need to. Their setup ran fine that way.

Sent from my SM-G928V using Tapatalk
 
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TRS

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Looking good Tony. You make this look so easy. Any pics of your "Shop"? Tool room equipment, or CNC, or 'have a friend".
Press fit on the injector housings? What's holding the throttle bodies in, center stud? Did you keep the oil pump?

I know this won't be 29 bucks but if you are just piggy backing with the Vipec I hope you give us the final parts list and settings when your done. Looks "affordable" for the ol' Pro.

Old time lathe and mill.
There are snowmobile pics with my shop in them on the forum. No actual pics.
Throttle body is held in by an O ring in the Silber manifold. I also added a set screw.
Fuel rail and bosses were pretty easy. I press fit round stock into holes I bored in the top of the Silber manifold. Silbers manifold had injectors located in the bottom. Justin's design hit the bulkhead. I also wanted to incorporate the Polaris dampeners. So I needed to build a new fuel rail. I have tooling for Bosch injectors.
Will keep the oil pump also
Hope this makes sense, trying to type on the run.
 
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TRS

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It is up and running.
Picked up 200 rpm at idle. Starts at a half pull in the shop. AFR dropped .7-.9 from stock injector location.
Going to test it with an all stock calibrated ECU.
 

Turboegt

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Too funny!

I was thinking about this today, and how to go about accomplishing it. I am looking to delete the stock oiling system, and replace it with a mechanical gear pump to provide adequate pressure for a the turbo and alleviate the need for an electric pump. (Journal bearing Turbo)

My concerns lie within the PTO and MAG bearings closest to the seals, and whether or not they would get ample lubrication with a stratified pre-reed premixed fuel injection setup.

I just built a new bottom end and top end due to a PTO big end bearing, and PTO case bearing ****ting the bed, and really don't want to do it again. It wasn't cheap. HAHA.
 

indydan

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Ohhhh! I have wanted to do this same project for years !!

And I get beat out by Grampa Tony ! :face-icon-small-ton

I really believe this will be the single best dependability improvement that can be done to the CFI 2 motors.

Getting fuel back to the crankcase from idle thru WOT should really help the longevity of the mountain motor segment !

Can't wait to see the results !

I have never been a fan of the cylinder located injectors..... IMO the 2005 900 motor was the best Polaris injection set up to current.

IMO- The 2006 900, Polaris started headed down the wrong road with cylinders injectors. I like fuel in the case

I really really like this idea !

WELL DONE TONY !
 
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mountainhorse

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Dan... sounds like you need to plan a trip to Cooke

We're all at least mid 50's.... so the grandpa quip hits a bit close... ouch !



.
Ohhhh! I have wanted to do this same project for years !!

And I get beat out by Grampa Tony ! :face-icon-small-ton

I really believe this will be the single best dependability improvement that can be done to the CFI 2 motors.

Getting fuel back to the crankcase from idle thru WOT should really help the longevity of the mountain motor segment !

Can't to see the results !

I have never been a fan of the cylinder located injectors..... IMO the 2005 900 motor was the best Polaris injection set up to current.

IMO- The 2006 900, Polaris started headed down the wrong road with cylinders injectors. I like fuel in the case

I really really like this idea !

WELL DONE TONY !
 
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TRS

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I'll post a report tomorrow. But... this thing is awesome. 63.3 grams at 10,000' with a 260# rider (before gear):face-icon-small-hap turns 8150 to 8200.:face-icon-small-hap:face-icon-small-hap:face-icon-small-hap
 

TRS

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I'll start with the sled.
2012 Pro
Avid drop and roll
162x3" 3.0pitch x3
8t 3.0 pitch avid drivers
19-46 gear set

MTNTK 5' tunnel cooler with BRP $28 upgrade
Runs 98* to 104*

Indy Dan long rod
H7, new rings last month after 500mi on engine
Indy Dan light weight crank last month at ring time

Stock pipe and can
Stock reed valves with stuffer removed
Stock ECU

BR9EYA plugs

Center to center is 11.5"
Lead in .020"
Offset .00"
Float .030" out

Primary(stock PRO uncut)
63.3 gram Lightning weights
140-330 primary spring
Secondary
120-200 spring
42-32F ER helix
Gates belt

TRS modified Silber intake manifold and TRS built fuel rail with PII dampers and PII yellow injectors(swapped mag to PTO)

-------------------------------------------

Is 98-104 to cold for this app? I don't know yet. Seems to handle it just fine compared to the cylinder injector app. Stock form runs to rich at that temp. The additional cooling is great on the trail. May try the old storm, XCR thermostat housing and 125* thermostat.

-------------------------------------------

Ok, Justin ran a whole tank of fuel through it yesterday. I did not ride it, but I did go for a putt putt ride on my '15:face-icon-small-coo

This thing needs fuel, had to run it in eth mode with 91 octane to stop det mode. A Bully Dog may be the answer here.

It is very responsive at every throttle position. I believe it needs more fuel coming back down to idle. It acts lean, high idle speed for a few seconds before settling in at 1900rpm. It may need fuel to puddle in the case to drop back to idle quicker. Remember flat slide carb sleds?

Justin weighs 260# before gear(sorry buddy). Justin's comment was t "it pulls so hard on my arms". Glade did a few climbs on Gardner headwall with it and his comment was "that thing is just stupid".
I am reporting what I witnessed and what they informed me on operating RPM. Historically My set up '15(long legs)would walk away from the '12 in a drag race without a problem. Yesterday that gap was closed up.:face-icon-small-hap huge weight differential between Justin and myself along with the parasitic 3" track.

It will run up to 8300rpm on the trail to the Beartooth Warming Hut.
Operating 8050-8200rpm from there to 10,000'. It spends most of the full throttle time in the 8100-8150 range. Making pulls in the trees and open hillsides. There were many near vertical climbs. The snow ranged from a few inches of new yesterday to deep heavy snow. The east side of the mountain got pounded with snow and the west side received much less.

At Gardner headwall the boys made at least 10 back to back pulls up the face. It's roughly a 1000' altitude change from the bottom to the top. With what I would call a 3/4 mile run. At the top of the climb the rpm range was from 7950(once) to what Justin thought he saw 8200(once). It hung in the 8050 to 8150 on most climbs at WOT. Did we stop and check belt temps? Nope, told Justin to drive it like he stole it. We know it hits 85mph down Gardner headwall on the speedo.:face-icon-small-hap What's that with the 8t drivers?
We took a couple videos of the runs up Gardner, I will see if I can load them.

I believe Polaris needs to move the injectors either into the throttle bodies(as Cat did) or build an injector throttle body manifold.
Would like to get 1000 miles on this setup and then tear it down.
 
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