Plugged Exhaust Valves?

Kraven · Oct 21, 2009

Daggerboat said:
If polaris delays valve opening RPM for emissions , can we assume that disableing this may help prevent the lean midrange....Or is this a fine tuning of the torque curve for these new motors....I just installed a digatron to help with dialing in my '07 600 this winter but has anybody with EGT's experimented with plugging this vent....Also , for the 600 carb the RPM is delayed till 6700 or 7200 depending on throttle position

On the bold, regarding mid-range LEAN condition, NO THIS WON'T HELP!

I installed a PC III :face-icon-small-hap on my D-7 to cure the mid-range lean condition @ 5000+/- R.P.M. added 5-7% more fuel, runs perfect now, and before the "stumble" was so bad it seemed like the sled "shut-off"

pj8556 · Oct 21, 2009

I guess I need someone to explain to me this whole deal in greater detail...?

pj8556 · Oct 22, 2009

can someone please elaborate on this more, i dont completely understand

Daggerboat · Oct 22, 2009

Do you understand how the exhuast valves alter exhuast port timing for maximum torque at different RPM's and only want to know more about the solenoid that opens and closes the vent ?

pj8556 · Oct 22, 2009

i understand the theory behind the exhaust valves opening and closing, i am unfamiliar with the polaris design, am new to the sleds. how exactly does it work, what is the flaw warranting the mod, and what do i have to do in order to do it. thanks!

Kraven · Oct 23, 2009

pj8556 said:
i understand the theory behind the exhaust valves opening and closing, i am unfamiliar with the polaris design, am new to the sleds. how exactly does it work, what is the flaw warranting the mod, and what do i have to do in order to do it. thanks!

The exhaust valves stay closed for good bottom end performance and open fully for good top end performance.

The emmissions solenoid just DELAYS the opening of the exhaust valves and thereby losing some performance/acceleration.

As far as warranty goes, it can be returned to stock in 5 minutes so no issue there.:face-icon-small-hap

You can leave the solenoid, wiring, hoses all on the sled. Just plug or cap them @ or near the exhaust valve.

towngrunt · Oct 23, 2009

There has been suggestions to plug these in 2 different manners, one being individually and the other just plugging the hose coming off the solenoid, which is best? Also I have a 06 600 with the solenoid, would I need to do this as well and if so what spring to install in it?

Kraven · Oct 23, 2009

towngrunt said:
There has been suggestions to plug these in 2 different manners, one being individually and the other just plugging the hose coming off the solenoid, which is best? Also I have a 06 600 with the solenoid, would I need to do this as well and if so what spring to install in it?

The manner of plugging (combined or individually) is personal preference as long as you plug 'em.

Use a spring from a 2004 600, for your 2006 @your elevation, lighter exhaust spring for higher altitudes.

Daggerboat · Oct 23, 2009

Risks of plugging the vent ?

With the variable ignition timing curves being used on these motors I think caution should be used when disableing the ECU/CDI control of the valves....Once I've recorded the maximum EGT's in the 6000 to 7200 RPM range at various throttle positions , I'll plug the vents and watch the EGT's carefully....My guess is that if there is any change in EGT's , they will be lower....If this is true then on cold morning at low elevations EGT's could be kept lower on my carbed '07 600 that's jetted on the edge...Anyone considering plugging these vents needs to remember that any performance gains will only be BELOW 6700 RPM at full throttle ( for the carbed 600 anyways)

DOLLYLLAMA · Oct 25, 2009

If someone could post some pictures of this, that would be helpful and much appreciated.

thefullmonte · Nov 18, 2009

So how many people have experimented with this? I'm curious if anyone has the specs for the springs? I'm looking for possibly a chart with starting rate and finish rate. These are the springs SLP has listed. The 800 dragon uses an orange spring. Possibly the same one listed by SDCoyote. Seems like the older 800's had a yellow spring? Does anyone remember?

14-113

Yellow Exhaust Valve Spring - Load: 2.4 lbs @ 1" and 3.6 lbs @ .63"

14-117

Pink Exhaust Valve Spring - Load: 4.7 lbs @ 1" and 7.1 lbs @ .63"

14-118

White Exhaust Valve Spring - Load: 1.6 lbs @ 1" and 2.8 lbs @.63"

cascadesnowjunky · Nov 18, 2009

my old 03 800 edge came with pink springs stock, but not sure if polarises spring rates and colors coincide with slp's, I have been curious about this for a while now. I am wanting to try disconnecting the hoses and running my 09 old school, as I have never been able to pull rpm's no matter what clutching I run. This will at least eliminate the possibility that the valves are not opening, and there is another problem.

Kraven · Nov 18, 2009

thefullmonte said:
So how many people have experimented with this? I'm curious if anyone has the specs for the springs? I'm looking for possibly a chart with starting rate and finish rate. These are the springs SLP has listed. The 800 dragon uses an orange spring. Possibly the same one listed by SDCoyote. Seems like the older 800's had a yellow spring? Does anyone remember?

Monte,

With regards to the exhaust valve spring for an 2002 EDGE 800, I can't remember the stock original spring color, but I definitely remember the "high altitude" springs being yellow, lighter tension than stock, there was a tech tip in SNOWTECH magazine that persuaded me to try 'em for our trips out West, don't know if it was POLARIS or SLP, but I still have the springs in my tool box, sled is long gone otherwise I would verify stock spring color.

Hope this helps.

cascadesnowjunky · Nov 18, 2009

does anyone know the spring rates on the stock orange springs in the new 800's.

Daggerboat · Nov 18, 2009

Effect to EGT's when plugging the vent

Daggerboat said:
If polaris delays valve opening RPM for emissions , can we assume that disableing this may help prevent the lean midrange....Or is this a fine tuning of the torque curve for these new motors....I just installed a digatron to help with dialing in my '07 600 this winter but has anybody with EGT's experimented with plugging this vent....Also , for the 600 carb the RPM is delayed till 6700 or 7200 depending on throttle position

Just as a follow up , I can confirm that EGT's are slightly lower below 6700 RPM with the vent hose plugged (This is good to know on those really cold mornings at low elevations)..... There is no change in the EGT's above 6700 RPM as expected ('07 600)

Mandic · Nov 18, 2009

Just going off of the Polaris Parts system but looking at it, my 08 Shift with a 600HO has the same exhaust valve springs as my Dad's 02 600VES (both pink). Right down to the exact same part number.

I looped a piece of hose between the 2 ports, placed a stud in the hose with some silicone and put a clamp on it. Looks like they are tied together, but they are independent of each other.

SD Coyote · Nov 19, 2009

cascadesnowjunky said:
my old 03 800 edge came with pink springs stock, but not sure if polarises spring rates and colors coincide with slp's, I have been curious about this for a while now. I am wanting to try disconnecting the hoses and running my 09 old school, as I have never been able to pull rpm's no matter what clutching I run. This will at least eliminate the possibility that the valves are not opening, and there is another problem.

The 04 800 RMK also had a pink spring stock. It is also the same rate as the slp one Monte has listed. All 3 springs he listed from slp, coincide with the polaris springs, color and rate. The orange spring in the 08 D8 is the same part # as the orange spring in the 04 700 RMK. The rate is 5.5 @ 1.0 in and 8.3 @ .630. Monte; the ev spring chart, with rates would be in the file I gave you on page 3.50.

thefullmonte · Nov 19, 2009

SD Coyote said:
The 04 800 RMK also had a pink spring stock. It is also the same rate as the slp one Monte has listed. All 3 springs he listed from slp, coincide with the polaris springs, color and rate. The orange spring in the 08 D8 is the same part # as the orange spring in the 04 700 RMK. The rate is 5.5 @ 1.0 in and 8.3 @ .630. Monte; the ev spring chart, with rates would be in the file I gave you on page 3.50.

Thanks for the info SD :beer; I wasn't at home when I posted that, but I figured I probably had it somewhere. So, it sounds like the pink spring would be a good place to start if someone was to plug the solenoid ports on the valves.
I came across another thread about this. Ron was thinking that although you may increase acceleration, you may loose some engine braking. Deceleration would potentially hold the valves open longer. Whereas the solenoid would close them almost instantly.
I'm still in the air about this. I'm only considering it to reduce heat around the exhaust port. If anyone was playing in the trees for any length of time it could get pretty hot.

600xc4me · Nov 19, 2009

Well this is a cool idea. i went and ordered the pink springs today. Should have them around the beginning of next week. Can some one post a pic of where exactly you plug it? Do you still leave all the hoes in place? I don't really care is they are plugged individually or still connected.

Kraven · Nov 19, 2009

Plugging the exhaust valve hoses

600xc4me said:
Well this is a cool idea. i went and ordered the pink springs today. Should have them around the beginning of next week. Can some one post a pic of where exactly you plug it? Do you still leave all the hoes in place? I don't really care is they are plugged individually or still connected.

Easiest way is to remove the "T" and replace with a 5/16" stud approx 2"- 2 1/2" long (bolt with the head cut off will work fine) clamp and you're done. It will look like the cylinders are connected, yet they're plugged individually.

The hose going to the solenoid, tie wrap it up, doesn't matter as the opposite end is vented to the atmosphere. You may need to reconnect this if you have to bring your sled in for warranty purposes.

Do NOT disconnect the wires going to the solenoid, this will cause an error message to pop up on your MFD display.

Hope this helps

Plugged Exhaust Valves?

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