journeyman
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Not to start any arguments but Hurricane's knock sensing is what sells it for me. Dave and company hit the nail on the head and as far as I know they haven't had a single engine failure since they developed their system.
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No one talks about their engine failures. I've overhauled them all, no one is on a pedestal! They all make good products, they can all be damaged as well, some guys can break an anvil.
I am not sure what to make of anyones knock sensor implementation. The knock sensor is already on the engine. The ECU therefore presumably has a method to incorporate 'detected knock' into the timing/fuel adjustments. Similar to how the ECU can read AFR from an O2 sensor and provide some kind of modifier to the existing target tables. While I am sure there is some tweaking that has to be done in order to understand when you really are in a true pre-detonation scenario, it otherwise seems to be more of an extension of what exists already. Put another way, I am not sure how much invention there is vs experimentation to ensure that the existing data is taken into account.
PEFI testing knock sensor data (jump to 0:44 for the money shot)
sledding rocks
Expert
the quality is amazing , i purchased there intercooler , the weld is amazing and the fit was perfect ,
So i hear that PEFI is not using closed loop and was told because tune is perfect. I am sure they are dialed in for sure but how can it adj for temps and elevation as good as a closed loop system, it cant can it?
The only way you can have a 'perfect tune' is if the external conditions do not change. Any change in temperature, altitude, etc will change AFR.
Doc Harley
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Please forgive if I am incorrect. Didn't I see a fairly resent vid of you guys tearing up a dyno with a sick 1049turbo SRX?!
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Trailleader
Expert
I ran pefi stage 3r back when you had your 998 and never had issues with the knock protection then and that was in 18/19.
They test their tunes with 2.5 inch exhaust that’s restrictive and doesn’t flow like the 3 or 3.5 inch exhausts. In turn we make more power and sometimes it can get a bit on the edge with low outside temps and n Wi gas! Imo closed loop on trail would be better but I also know you know motors. The tunes are all good
Nothing you would worry about this season! Lol
Here's my .02c
If you buy a package from any of the tuners and only run the hardware they have built their tunes around you will be unlikely to have any issues.
But...if you are like me and can't leave well enough alone, and you start to mix and match intake and exhausts that the tune was not designed around you are heading into no man's land! When you then add in questionable fuel and very cold and high pressure environmental conditions you end up relying on the engine protection modes to keep your engine alive....not good and none of us want to go there intentionally.
This is where closed loop comes in for people like me to save my engine from myself and still keep the vendors deto protection as a fail safe which is what it is designed to do.
JM.02c
If you buy a package from any of the tuners and only run the hardware they have built their tunes around you will be unlikely to have any issues.
But...if you are like me and can't leave well enough alone, and you start to mix and match intake and exhausts that the tune was not designed around you are heading into no man's land! When you then add in questionable fuel and very cold and high pressure environmental conditions you end up relying on the engine protection modes to keep your engine alive....not good and none of us want to go there intentionally.
This is where closed loop comes in for people like me to save my engine from myself and still keep the vendors deto protection as a fail safe which is what it is designed to do.
JM.02c
KnappAttack
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Might want to re-think that and research the early days of the tunes and knock detections prior to you being on the forum.
When Hurricane Dave was implementing the work on getting the det protections up and perfected with GAP on the dyno and knock ears, he said the knock protections were not working properly with the stock setup back in the early years of adding the tunes. He had around 5-6 engines go down early prior to activation, I had a buddy with one of the engines, and Hurricane paid for the engine work at the local dealer to get it back up and running back then. Pretty stand up company that does that!
Dave spent days perfecting the det protections on the dyno, listening for knock, dialing it in and perfecting it. Since he's done this, Hurricane has not had any deto damage to my knowledge. PEFI on the other had has had a rash of problems, so I dont think banging the knock sensor on the handlebars qualifies as testing the det protections properly.....
Delphi also uses knock ears to develop the OEM auto manufactures engines knock protections the same way Hurricane did the testing on his dyno with the 998. He refuses to turn down the sensitivity on the protections, I've heard of the sensitivity being turned down by others, true or not, I don't know, but I have not heard of any Hurricane tunes going down from deto since the implementation of the knock detection into the tunes.
I'm not so sure Turboflash or Kinger would agree with the PEFI detections working so well.... Of all the tunes out there, it seems there is one company having many issues on the 998, I know of one that went down just using there 250 tune, right from the dealer that installed the tune..... A 250 tune should not even be pushing it! They are the one that stands out more than all the others for having engines going down since the early days.
Might want to read thru these couple of threads. 998-engine-rebuild.163092. gap-flasher-feature-presentation-active-knock-protection.150796
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Could very well be that the knock detection wasn't working in early units, but I know if you bang on the knock sensor the sled is detecting it.
I read Daves original posts (I have been a lurker on the forum for a lot longer than I have been a full member) I also read the posts around others stealing his knock detection and tuning work.
Specifically, my comment that "I don't know what to think about anyones knock sensor implementation" was more about how little control the tuners really have over the ECU and that if the knock detection is already there, then they are just learning/modifying/tweaking, less invention. more about integration, but my comment was really more in line with what I read between the lines from all of Daves shared information and even back then it felt like he was the only one doing the real work to understand how it all fit together so my comment was more about 'the others'. I can see how some other tuners might push the envelope more without really understanding the ramifications or simply classifying the particular operating parameters as unlikely to happen in the real world. Then some poor customer runs into that exact situation and pays the price.
You see this a lot in the car world, tuners making decisions and taking risks that the original engineers would never make all in the name of selling tunes.
Well I have to chime in on this one because I'm not sure how many people have had the opportunity to witness live data info on a stock tune as I did. I have had my share of experience with these tunes and I must say I was absolutely shocked what the AFR's were when I ran the stock tunes with an Adjustable FPR, big pump and AFR module. The AFR's were WAY too high for my liking on the stock tune. Anybody running an aftermarket muffler or out of the hood CAI is really risking it IMO. I had done some simple stock mods on the stock tune and had to run 46 lbs key on to keep AFR's in check. Mind you 43.5 is stock key on. I only wish I could have seen DATA Logging while stock, but it is not possible. My guess is if there is any type of in system detection it would be pulling timing like mad but we know there is no stock O2 sensor so AFR's are not available to the ecu.
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Turboflash
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Agree. I think it's safe to say all 3 of the main tuners develop their tunes using their own hardware. Specifically, I think it's pretty common knowledge PEFI's 2.5" "performance muffler" is likely the most restrictive 2.5" PM out there. So, when we start to mix other manufacturer's products into our tune (ie 3" Sandale) we have now departed into uncharted territory. It is now on us to own the consequences. I think if one runs 100% of the chosen tune and hardware from any of the tuners, for the most part we should be safe (yes there's bad gas, super-cold temps, etc).
If we depart from that, we'd better have whatever it takes to monitor our sleds performance and make required changes to stay safe. IMO, at the minimum, AFR info, and moving up to data-logging.
For example, I run PEFI stage 4 w 3" Sandale which flows more than PEFI's 2.5" PM. I have AFR gage and could easily see increased flow resulted in unacceptable WOT AFR. Using my adjustable TD FPR, all I had to do was turn up FP a couple pounds and AFR is now safe. Without AFR (or better yet - data logging) I wouldn't have known AFR was unsafe.
The knock detection needs to be viewed as a seatbelt imo. It is there to offer you safety and many times will do its job to protect you but it doesnt guarantee survival. Im surprised we dont hear more of engine issues because usually people hit facebook or forums to complain about the issues they had with a product but with the engine failures it remains hush hush for the most part. My local dealer does alot of engine and tuning work on these sleds as people travel from hundreds of miles away in the states and canada because they trust his work. He has shown me many pictures and actual parts from all kinds of failures. PEFI got a bad rap from mostly the stage 3 280 tune and in the end alot of end users were running high flow mufflers and cold air intakes and the tune was designed for their muffler and stock airbox. They later updated their website to include this info. Stage 2, 3R and 4 say you can run their muffler or other 2.5" mufflers. My dealer began selling their products and tunes about 2 winters ago to add another option for customers. He personally knows a couple sleds in canada with over 12,000 miles on stage 4 with zero engine issues. My buddy had a 3R tune on his old cat RR that was pushing 6000 miles. He is not easy on sleds and gasses at the pump rarely using additives of any sort and had zero engine issues. Sled had fuel pump start to fail and was down 2-3 psi and knock light would go off every single time he strapped it to the bar. Yet others have reported a non functioning knock light. I wish PEFI attention to detail and workmanship would of caused others to feel the need to up their games to match but unfortunately that wasnt the case so PEFI remains #1 in that department with most everyone else 10 bus lengths behind. I have ran thousands of miles of TD and hurricane tunes and not had any engine problems as of yet. I am also just a trail rider and do keep a close eye on things and make sure everything is in check at all times. That can go a long ways in itself. Also Im sure if you spoke to all of the tuners you would hear alot of different opinions on everything. There was talk of the factory knock protection not being adequate for anything other than a stock tune. Ive had conversation with Viktor Paullson of maptun in sweden and they use maptuner x as the tuning platform for their tuning on powersports. He said the factory knock protection sensitivity can easily be adjusted for sensitivity by the end user if they want more sensitivity than maptun sets them at. They may not be a popular option in the states but they are a big tuning company in the powersports and automotive world with all the latest and greatest knock detection equipment, dynos and other tuning tools. They feel what they do is adequate for protection. Ben at Td does what he feels is adequate. Him and the other quebec guys as well as alot of the northern maine guys go from one end of the world to the other and back again strapped to the bar with mostly success. They all believe in their product and often times their end users believe what they have is the best so its hard to decide sometimes what to do. Like Ulmer said earlier, every single one of them can blow up. That is fact and assuming you wont ever have any issue because you have a knock light and never see it is a recipe for disaster in itself. Best a guy can do is go is research and go with his gut if its his first tuning experience or go with what he is comfortable in using from past experience if hes a tuning vet. AFR gauge is always a good choice for safety and is a very small price to pay even if you are 100% inline with hardware requirements and should be "safe" . More info available the better your chance of success.