Has anybody had problems after installing high compression head?
- Thread starter 800poodragon
- Start date
T
theultrarider
Well-known member
It's not Just a matter of milling them. You should see the shape of the inside of the stock head. They are not a typical 2 stroke hemisphere spherical head. All the aftermarket ones are
R
RKT
Well-known member
If you mill the stock head you WILL lose power and compromise the engine.
heads today are not as crude as they were 55 or even 10 years ago
Be careful
Brutis20 YES my tests conclude decisively that you can run a stock exhaust system with this head. As a matter of fact it WORKS 
fantastically.
I've also ran 800CFI motors with added compression and per other referenced comments my experiences were not as consistent nor near as positive as just simply installing this head that is a better design and more appropriate for performance at the altitudes that we ride.
also note that I do put a couple oz of red line directly into my fuel on each fill...don't really know if it makes a difference but I've had no ring issues and my sled RIPS compared to others so it must not hurt...kind of like taking your morning vitamins...some say you get them in your food if you eat right and they really don't do anything, but they clearly don't hurt, so I still take em. And look I perform pretty well too for a the train wreck that is left after all of these years of abuse!
fantastically. I've also ran 800CFI motors with added compression and per other referenced comments my experiences were not as consistent nor near as positive as just simply installing this head that is a better design and more appropriate for performance at the altitudes that we ride.
also note that I do put a couple oz of red line directly into my fuel on each fill...don't really know if it makes a difference but I've had no ring issues and my sled RIPS compared to others so it must not hurt...kind of like taking your morning vitamins...some say you get them in your food if you eat right and they really don't do anything, but they clearly don't hurt, so I still take em. And look I perform pretty well too for a the train wreck that is left after all of these years of abuse!
Ok, now that most of the warranty work has been denied I will let you all in on what caused this thread.
I purchased a 2011 Pro 800 via snowcheck. Ran good but never really happy since my father also had a 2011 Pro 800. Gotta be better than who you ride with. So I added an SLP single and V-Force III Reeds at around 800 miles and it sounded better but neck in neck with stock Pro. At 1100 miles (summer) I purchased an SLP head to go up to Stage III. Once again....neck and neck with stock sled first time out is in upper 30's and around Dec 9th. Then I go up to my time share for a week on December 30th. Sled fouls at least one set of plugs each day and runs horrible. Almost every day is around 20 degrees or colder. One of these days, we had to pull the sled out of the trailer by hand even with fresh plugs. Sled had been acting up when cruising or running at an rpm that wasn't accellerating nor was their a load on the motor. If you were standing...it would feel like you had the throttle open and somebody hit the kill switch. Determined to be injectors. Easy fix. Last day there I got to ride the sled but it ran better but not like it should have. Drop sled off at dealer when I get into town. Dealer goes through and rechecks tps and Power Comander and did some little tweaks. Think all is fine. Get down to West Yellowstone and it takes 3 sets of plugs to get from hotel to West Yellowstone Polaris. Start hearing rumours about what it could be. Pay to have reeds inspected. They are horribly chipped up and not sealing. Install stock reeds back in sled and installed a new pipe temp sensor. Sled is kept inside until I pick it up on last day we're there. It runs without fouling plugs right away but does foul one set when I get stuck. Bring sled back to my dealer. Go with rumour and have top end taken off. Rings are chipped/flaking. Seems to only be happening where the intake ports are. Discuss this all with dealer and with others. If sled was warm or kept inside at a warmer tempurature the rings weren't bad enough to fail everytime. Mainly they only failed or showed failure when cold. Some of us feel that this was probably there for a long time since I never did see any advancement of performance with any of the go fast parts I added. However, others think it was the go fast parts.
Dealer told me that they didn't disagree that the rings were bad and possibly bad on any stock sled. Just that the head/pipe/pc5 combonation magnified it and if I had kept it stock I may have never noticed it. 800Poodragon uses same dealer and was told to remove his aftermarket head due to what we saw on my sled. So he started this thread to see if anybody else had issues.
Also, some of you may remember the thread about the SLP Stage III nightmare that had the title changed. Well that guy finally tore apart his motor and guess what? Rings were even worse than mine and piston even had some damage....right where the intake charge comes in the motor. I want to stress that the two instances that I speak of were on sleds with over 1000 miles on them.
I am not saying one way or another who is at fault but a spade is a spade and if somebody can tell me how rings and/or pistons get damaged in only the area that the intake charge comes into the motor and can blame it on the PC5, pipe, or head...I will listen to you. I am only presenting the facts and you, snowest users, can make your deduction from the facts.
I really hope that I am one of only two peoples to have this issue surface. I am now done and I am not going to speak of it again on the forum.
I purchased a 2011 Pro 800 via snowcheck. Ran good but never really happy since my father also had a 2011 Pro 800. Gotta be better than who you ride with. So I added an SLP single and V-Force III Reeds at around 800 miles and it sounded better but neck in neck with stock Pro. At 1100 miles (summer) I purchased an SLP head to go up to Stage III. Once again....neck and neck with stock sled first time out is in upper 30's and around Dec 9th. Then I go up to my time share for a week on December 30th. Sled fouls at least one set of plugs each day and runs horrible. Almost every day is around 20 degrees or colder. One of these days, we had to pull the sled out of the trailer by hand even with fresh plugs. Sled had been acting up when cruising or running at an rpm that wasn't accellerating nor was their a load on the motor. If you were standing...it would feel like you had the throttle open and somebody hit the kill switch. Determined to be injectors. Easy fix. Last day there I got to ride the sled but it ran better but not like it should have. Drop sled off at dealer when I get into town. Dealer goes through and rechecks tps and Power Comander and did some little tweaks. Think all is fine. Get down to West Yellowstone and it takes 3 sets of plugs to get from hotel to West Yellowstone Polaris. Start hearing rumours about what it could be. Pay to have reeds inspected. They are horribly chipped up and not sealing. Install stock reeds back in sled and installed a new pipe temp sensor. Sled is kept inside until I pick it up on last day we're there. It runs without fouling plugs right away but does foul one set when I get stuck. Bring sled back to my dealer. Go with rumour and have top end taken off. Rings are chipped/flaking. Seems to only be happening where the intake ports are. Discuss this all with dealer and with others. If sled was warm or kept inside at a warmer tempurature the rings weren't bad enough to fail everytime. Mainly they only failed or showed failure when cold. Some of us feel that this was probably there for a long time since I never did see any advancement of performance with any of the go fast parts I added. However, others think it was the go fast parts.
Dealer told me that they didn't disagree that the rings were bad and possibly bad on any stock sled. Just that the head/pipe/pc5 combonation magnified it and if I had kept it stock I may have never noticed it. 800Poodragon uses same dealer and was told to remove his aftermarket head due to what we saw on my sled. So he started this thread to see if anybody else had issues.
Also, some of you may remember the thread about the SLP Stage III nightmare that had the title changed. Well that guy finally tore apart his motor and guess what? Rings were even worse than mine and piston even had some damage....right where the intake charge comes in the motor. I want to stress that the two instances that I speak of were on sleds with over 1000 miles on them.
I am not saying one way or another who is at fault but a spade is a spade and if somebody can tell me how rings and/or pistons get damaged in only the area that the intake charge comes into the motor and can blame it on the PC5, pipe, or head...I will listen to you. I am only presenting the facts and you, snowest users, can make your deduction from the facts.
I really hope that I am one of only two peoples to have this issue surface. I am now done and I am not going to speak of it again on the forum.
WOW, interesting. Glad you are getting to the bottom of that one. Good deal.
http://www.snowestonline.com/forum/showthread.php?t=290946
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Yes...looked good @ 107 & 104. Problem is the compression is like four times more when firing so it didn't show as a problem. Funny how I no longer feel like LeeHarvey Oswald the lone gunman, hearing about a lot of people with exact same issue.
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2mileshigh
Active member
I have the same set up, you need to run 2 gal of race fuel, 110. Your problems will be solved. Ride 9 to 12k
actually 2mileshigh and bajah2x you absolutely DO NOT have to run any higher octane than 91 on a Power Addiction 13.6 head with stock exhaust on a PRO at those altitudes. If you are having laying down issues at midrange it's from clutching not the head v octane burn. The setup must be loaded and correct clutching is really important. If you are running 93 octane at those altitudes you are leaving tremendous performance on the table. The key to excellent performance is running the exact correct octane to your environment. You've slowed down your burn rate so much that you have essentially reversed the benefit of the higher compression head. At high RPM (7400-8000) on 94 octane at your altitude you have knocked off about 20% of your available power. Run 91 and clutch your sleds correctly...it will be an entirely new beast. I have actually ran 87 oct at your altitudes and it's another notch quicker to duration. The sleds will feel just like they do at 6000ft with 91 and a 13.6 head. (but this in not he manufactures recommendation so that is an at your own risk proposition...BUT IT DID)
(AND PUT EXTRA OIL IN to protect your rings...see how we tie the threads together to keep the internet forum nazi's at bay)
(AND PUT EXTRA OIL IN to protect your rings...see how we tie the threads together to keep the internet forum nazi's at bay)
C
cmrmk
New member
So what are you running for weights.I have the same 12.5.Was going to put 10-64's on with the new head up from the 10-62's at stock
I went with slp weights and problem solved, no more det. I cant believe how much better its working.Have been riding as low as 7000 and no problems with 91 fuel.
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2mileshigh
Active member
Im running MTX wts. How much did you end up with.
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theultrarider
Well-known member
I ride mostly at 2-3000ft. At that elevation I pull a dead even 8k rpm with 71 gram mtx weights loaded with 2grams in each of the holes for a total of 75grams. That is with a 60/40.36 with a stock secondary spring, and an slp blue/pink in the primary. I'm gonna try stepping up to a 60/42 here next week and see if it will pull that without my r's starting to jump around. I'm a large guy on a 163 so I generally need to stay alittle shallower on the helix than alot of you smaller guys on 155's to keep my r's constant.
I am using 65 grams with a blue pink primary,stock secondary.
M
mynewuseddoo
Well-known member
Umm, no...... I ride with Pro's with 3" 174's. I smell a teeny tiny bit "O" BS here. I'm sure it's a ripper but 8 PSI boost and a high compression head are very different. Now, run a high compression head on a boosted sled.....holy throttle response!
2
2mileshigh
Active member
Im having a hard time believing more clutch wt, will cure DET issues.Ordered the clutch kit from Carls today. Chris at Carls seemed to somewhat agree. But I will try it and see.
