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pix on 14 pro meltdown

D
Nov 14, 2013
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Little more info, agree or disagree lol. thanks for the replies from all of you by the way.

Ok after me consulting a couple guys and my turbo kit guy consulting MANY experts and reviewing the several logs they had access to it has been determined it is not detonation, but if anything pre ignition. Why is the thing we are trying to narrow down. One VERY respected polaris guru came out and said this very likely could have happened last spring breaking it in, pre turbo. All is a bit of speculation at this point, but these guys have Way more knowledge than i or most others for that matter. Bad fuel??? maybe we now know we were over boosting a bit, so maybe some of that?? fuel delivery issue or excess air entering they system somehow????? ruling some things out, and will be testing for some once sled is back together.

Turbo kit man has been doing everything to try to find a cause and solution, even sending me some stuff to help get it back together.

I was feeling like a complete idiot thinking i wasn't hearing the detonation, but now appears i was not hearing it cause it wasn't there. Deto meter did not go above dangerous levels according to log.

Hopefully this was just one of those things that happens, and when put together it will run great, but definitely will be double checking a few more things and will be keeping a eye on the fuel quality as best as i can

I purposely left out the kit company, so this couldn't turn into a bashing of him, since this, in my opinion, was not a kit issue. Any issue more than anyone adding a turbo to a two stroke anyway LOL.. Some of you have figured out who's kit it was and started ringing him with calls. That actually helped to rule some things out, so thanks for that too. There is a lot of behind the scenes knowledge on these forums.

thanks

I am no expert in this, so if i might have screwed up a explanation or two in this post sorry.

I have an hm turbo kit with vipec and we were running a pump gas kit to begin with.

6lbs of boost and pump gas at that elevation will result in DET

The vipec has the ability to store DET but as far as I know they were unable to make the fault to appear on the dash

You have to set the threshold on the Vipec to store a DET code, if the threshold was set too high then it wouldn't store any DET codes

If you were overboosting and running that low of octane, your problem is pretty simple, DET

Don't bother taking a chance, mix in some AV.

Were you running EBC on this sled??
 

yammi4ever

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I have an hm turbo kit with vipec and we were running a pump gas kit to begin with.

6lbs of boost and pump gas at that elevation will result in DET

The vipec has the ability to store DET but as far as I know they were unable to make the fault to appear on the dash

You have to set the threshold on the Vipec to store a DET code, if the threshold was set too high then it wouldn't store any DET codes

If you were overboosting and running that low of octane, your problem is pretty simple, DET

Don't bother taking a chance, mix in some AV.



Were you running EBC on this sled??

The threshold was set, and the log shows it did not go above critical levels. lends more credibility to the guys much more in the know than me who have said this is not DET. (not saying NO DET, just not what caused the burndown)

No was a vac actuator on the boost control. Have a new one on the way just in case

Most of the fuel in the tank was fresh 93, I do plan to run 91 or 93 depending on what i can get my hands on plus a couple of vp116 or torco (i know some people have different opinions on this, but it has kept my nytro alive for 4000 miles) to keep me off the ragged edge


thanks to all who weighed in both on here and in pm's and phone calls. virtually all who had nothing to gain by helping out
 

diamonddave

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The injectors in the 800 CFI-2 motor do not like torco. Please don't use it in this motor. This motor is not your turbo yammie.

Please use the proper octane needed for your elevation. Race fuel or Av Gas.

And btw....none of this carnage happened when the motor was stock! Period.
 

yammi4ever

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The injectors in the 800 CFI-2 motor do not like torco. Please don't use it in this motor. This motor is not your turbo yammie.

Please use the proper octane needed for your elevation. Race fuel or Av Gas.

And btw....none of this carnage happened when the motor was stock! Period.



"could have happened last spring breaking it in, pre turbo. All is a bit of speculation at this point,"



thanks for the opinion and info tho.

I am curious as to why a fuel octane booster might interfere with a injector? Care to elaborate on this some?? Not disputing at all, but curious why.

I do have access to av ll100 anyone have a opinion of how much to put in to a tank with 91 to give a decent margin of safety??? 3 gallon enough???
 
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Boyko

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Nov 27, 2007
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Its funny that when a turbo motor gets porked so many folks are saying the detonation monkey is on your back.

If your piston is burnt off at the crown by the exhaust port it is caused by a lean condition.

If you piston crown or the fist ring land is busted off its detonating, pre ignition is a much more severe condition than detonation


Deto monkey at work

detonateddome.jpg
 
D
Nov 14, 2013
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Its funny that when a turbo motor gets porked so many folks are saying the detonation monkey is on your back.

If your piston is burnt off at the crown by the exhaust port it is caused by a lean condition.

If you piston crown or the fist ring land is busted off its detonating, pre ignition is a much more severe condition than detonation


Deto monkey at work

Boyko would know better than I. I realize you do not want to throw the turbo guys under the bus, but please reveal some more info about your setup as there are a lot of things the turbo guys can learn from people on these forums......not speaking from personal experience or anything....My next question is, what injector setup are you running?

Boyko, looking at this pic (my sled last year,) you would say a lean setup? Not DET? Despite the plugs looking similar to yammiguys.

1263928_10153367273685157_1780502516_o.jpg
 

yammi4ever

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Boyko would know better than I. I realize you do not want to throw the turbo guys under the bus, but please reveal some more info about your setup as there are a lot of things the turbo guys can learn from people on these forums......not speaking from personal experience or anything....My next question is, what injector setup are you running?

Boyko, looking at this pic (my sled last year,) you would say a lean setup? Not DET? Despite the plugs looking similar to yammiguys.

from what i have gathered in the past 48 hours The experts would not call that DET. but a fuel delivery problem (bad fuel being one possibility) for what that is worth LOL.
 
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Boyko

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That piston pic I posted was just pulled off the web

I'm am not a expert or do I work in this field, I could be wrong, I make mistakes all the time.

My set up? I do 1 or 2 one-off kits a year on sleds but I prefer extra injectors blowing through the reeds.

Usually if you look at a plug right after a melt down its going to have aluminum stuck to it, hard to read a plug after the motor been run for a bit

I take it pretty easy on what I ride and don't break much stuff but I did taken out a set of pistons on a m1000 at low boost, straight AV fuel 2400 feet. they looked rounded off like yours. I had a A/F gauge with a needle (they suck)
it looked like it was high 13s

If you blow super hot exhaust out your port the piston crowns edge is probaly going to melt first.
 
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Boston Racing

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from what i have gathered in the past 48 hours The experts would not call that DET. but a fuel delivery problem (bad fuel being one possibility) for what that is worth LOL.


Lol. The real question is what is the side effect if a fuel delivery problem......detonation. Oh and the bad fuel.....there is that pesky detination again.

I agree that it could be a fuel delivery problem or an air leak but also remember an injector being programmed to not remain open long enough to provide the proper amount of fuel could also be described as a fuel delivery problem :)
 
D
Nov 14, 2013
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Lol. The real question is what is the side effect if a fuel delivery problem......detonation. Oh and the bad fuel.....there is that pesky detination again.

I agree that it could be a fuel delivery problem or an air leak but also remember an injector being programmed to not remain open long enough to provide the proper amount of fuel could also be described as a fuel delivery problem :)

Exactly, and there is no real question here as to why your sled grenaded......you cannot run 6lbs with a half decent running kit at that elevation on pump......

we tried 6-6.5lbs @ 7000ft with pump and my pistons pictured above were the result.

Call it what you want, get some av in that poo.
 

kiliki

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talking to a brick wall....You can call it pre ig or det or what ever the F you want lean and or bad fuel. you can not run the 6psi on pump at 0+ alt for more than a few. any turbo builder worth there salt knows the parameters of pump gas. turbos and pump gas+:frusty: not det light?
 
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Boyko

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I run at 0-1500' (hm turbo) on straight 91 at 7-8psi for 4 years now trouble free and all of our customers run the same with same results (push turbo, boondockers, silber kits). It all depends on the tune you are downloading to your ECU. Intercooler is a must to me and we all run them over here(of course they all run our ECU though)


Actually any turbo builder worth there salt will tell you detonation is controlled by ignition timing

Pre-ignition can not be controlled by fiddling with the timing curves in the ECU. It is eliminated with alterations to boost, fueling, compression, octane and or heat management

Stock timing wont work well at sea level with a turbo on pump but this guy is running a vipec and has control of his timing.

Detonation and running piston melting EGTs can be closely related,
-Run to hot EGTs and you are more prone to detonate or pre-ignition
-Detonate and you EGT goes up

Your A/F gauge wont tell you that your EGTs has gone up
due to detonation.
 
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D
Nov 14, 2013
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Originally Posted by Vi-PEC Powersports
I run at 0-1500' (hm turbo) on straight 91 at 7-8psi for 4 years now trouble free and all of our customers run the same with same results (push turbo, boondockers, silber kits). It all depends on the tune you are downloading to your ECU. Intercooler is a must to me and we all run them over here(of course they all run our ECU though)




Really? So what happened with the customer sleds for HM Turbos? 2 pistons shown above as well as a cylinder that required a re-nik begs to differ....We didn't get to inspect the pistons of my buddies sled as the EBC @ 11psi on pump took care of that motor. If you were running a different map then please do tell? Larger injectors? Sorry but a real sour taste for pump gas turbo sleds that we were promised, that didn't pan out. At the end of the day love my turbo sled, 3000 mountain miles (set of pistons and cylinder nik only complaints) but as the dust settles how about some real answers.


 
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Boyko

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I've seen the same type of piston damage before, even on stock carbureted sleds that were jetted incorrectly. One of them was a few weeks ago. I doubt deto was a issue on this carb sled because the sled ran fine and crisp at 0 Celsius, temp dropped to -26 and the dude had a midrange burn down. piston both looked the same as what was illustrated at the beginning of this thread.

Someone well experienced with the tuning the vipec could look what was logged in the ecu and have a better idea then you are I as to the cause, it might not be related to the tune.

Dan how long have you been tuning turbo 2 strokes for?
Do you know why the difference between pre ignition and detonation is so significant to a tuner?
 
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G
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looks lean and low octane.. but the devil is in the drive pressure.. without knowing that ?? do yourself a big favor,, pull the plugs and read them and your pistons from time to time ..sensors are not going to solve these problems until a human eye and a human mind tell them what is acceptable and when it is acceptable.. had you monitored your plugs daily this would not have happened to you.. 17 yrs of no failures and no tow ins gives me the right to say this..

as I ride daily we hear folks saying it must be a drag to be looking at plugs and pistons daily,, man I would get a better tuner.. then later that day we tow the same crew back to investigate the super ecu's logs as to why its locked up..

pull the plugs.. use your own mind..please..
 
D
Nov 14, 2013
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I've seen the same type of piston damage before, even on stock carbureted sleds that were jetted incorrectly. One of them was a few weeks ago. I doubt deto was a issue on this carb sled because the sled ran fine and crisp at 0 Celsius, temp dropped to -26 and the dude had a midrange burn down. piston both looked the same as what was illustrated at the beginning of this thread.

Someone well experienced with the tuning the vipec could look what was logged in the ecu and have a better idea then you are I as to the cause, it might not be related to the tune.

Dan how long have you been tuning turbo 2 strokes for?
Do you know why the difference between pre ignition and detonation is so significant to a tuner?

I have next to zero experience tuning turbo 2 strokes. What I have had is 3 years on a turbo sled that was delivered poorly to myself (and a friend who built an identical setup.) Through the first season we were left in the dark (as all Canadian customers were,) and did a lot of self education.

I am relaying only what I have learned/been told (which could have been all bs,) based on my experience running a Vipec controlled turbo kit. I have used the word DET too loosely.

I would assume the significance of det vs pre ignition to a tuner would be whether the issues are before plug firing or after? If not please elaborate.

As for my sled, I was told it was DET due to poor fuel quality and HM urged all their customers after that season was up to start running a minimum of 20% AV going forward.

This thread got me thinking about it again, we were running stock injectors on these sleds. HM had mentioned at about 6.5psi with their sleds we were using 100% of the stock injectors duty cycle. That is the reason I asked in a previous post if the piston crown melt I pictured could be caused by a lean condition? Though we had a third sled built that has ran basically spotless with 6.5psi and stock injectors.
 
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