We need to find a way to turbo our oddy's.
https://www.bing.com/videos/search?q=Tu ... ORM=VDMCNL
Start the vid at 45 seconds.
I think the announcer said 400 km/h. That's 245 mph

Just in case any of you yoyo's think it's a good idea, you should read this: http://boards.straightdope.com/sdmb/sho ... p?t=508263

got a head ache reading that thread - the snowmobile is bad a$$ tho.

I would like to revive this thread for moment. Below is a link from a site I got the info from and I am cut n paste the relevant info from that site. It all really starts at page two. Here is the site link: https://www.physicsforums.com/threads/a ... oke.64413/
Below is the cut n paste job:
Bluechipx: Can't easily turbo a two stroke? Wrong, wrong, wrong! I am a two stroke nut and have been for decades. I also thought that turbo'ing a two stroke couldn't work because it would simply blow through the exhaust port, wrong! About ten years ago I was at a snowmobile grass drag and the class was open fuel, anything goes. I noticed a sled with a turbo at the end of the exhaust stinger. I asked if they had done some major port moving or installed valves. The answer was no to all, it was basically a stock motor (( Internal Combustion Engine ? )) with turbo added. I replied that it can't work, to which the driver asked if I just arrived there. I said yes and he said to be at the starting line in ten minutes. I just about crapped when he left the line with well over double the original horsepower! I have since bought that very sled and experimented with a turbo on a two stroke mercury four cyl on a hydroplane. The motor (( Internal Combustion Engine ? )) I was using on the hydro was dyno'ed a shade over forty HP and good for 80 mph on a good day. I simple adapted turbo on the 40 hp motor (( Internal Combustion Engine ? )) made 85 hp on the very first dyno run and easily bumped to 100hp. Once you realise that it works, you can begin to figure out why. If anyone is interested or doubts this, I'll go into the simple explanation.
First off, reeds ARE valves, but I'm not here to argue minor language issues. Anyone that gets this far in this thread and feels two stroke turbocharging isn't practical, follow along and you, like myself will have an OMG! eureka!, moment shortly. On my way home from seeing a basically stock 700cc snowmobile with a turbo run with the biggest and badest stuff out there, a four hour trip, I was forced to rethink my thirty-odd years of thinking the charge would simply blow through the last to close exhaust port. At first I thought possibly the gain would come from getting a super clean, no residual exhaust, fresh charged cylinder, but with no real boost. But that wouldn't account for the doubling or possibly tripling of the horsepower. BTW, the racer that I bought the machine from said he ALWAYS had much more top speed than his competition, but it sometimes took a bit of catching up. Grass drag snowmobiles are dynamite off the line and the race is only five or so seconds long, so hole shot is critical. In my later projects of putting turbo's on two strokes, there is a bit of delay in throttle, but it's minor. I had a friend that choose the nitrous route against my smaller displacement turbo in the hydroplanes, and in an even start from a slow float, (thirty MPH or so) he would get about a twelve foot (one boat length) jump before I began coming back. Also, his nitrous was great on acceleration but didn't have much effect on top end, probably less than one MPH. The turbo was unbelievable for both acceleration and top end. It would quickly push the designed for 75-80 MPH hydro past 100 into high speed handling problems, so I never really saw what it would be good for top end. Also the motor (( Internal Combustion Engine ? )) was designed for forty HP and was really being pushed at one hundred HP. Back to the "why it works" basics. Try to clear your head of the blowing though the exhaust with no boost for a second and ponder the fact that it REALLY DOES WORK. See if it hits any of you with the jaw dropping effect it had on me when it hit me. I almost had to pull the car over to the side of the highway and compose myself. I'll get back and give you the answer tomorrow about this same time, so this is your one last chance to see if you can get it on your own once you know it works. Hint, it is not rocket science but simple basic logic that will make you feel like you should have seen it long ago. But who am I to talk. I was thirty plus years of getting it wrong.
Okay, here's where the mistake comes in about the common notion that a turbo will simply blow through a two stoke without creating boost in the cylinders. I have put a one way reed pressure gauge on a simple two stroke to check only positive crankcase pressure. At high RPM's the positive pressure in the crankcase was about 7.5 psi. The motor (( Internal Combustion Engine ? )) was not an expansion chambered motor (( Internal Combustion Engine ? )), but a simple non tuned exhaust system. When the piston is down and both ports are open you have a gradient of 7.5 psi on the transfer or intake and pretty much zero on the exhaust side, so the Engine will run fine with the 7.5 psi difference driving the fresh charge in and the exhaust out. For clarity, let's assume we are super charging for a moment. Now let's crank up the crankcase pressure to 27 psi. If the exhaust pressure was still zero, it would work like 99% of people think. Lots of wasted fuel/air blowing through the open exhaust port with minimal HP gains. Now here's the catch. Let's put a butterfly in the exhaust system near the motor (( Internal Combustion Engine ? )) and put a pressure gauge between the exhaust port and the open butterfly. With the motor (( Internal Combustion Engine ? )) running as we slowly close the butterfly, a pressure will began to build in the exhaust area. We know if you continue to restrict the exhaust until you have 20 psi, the crankcase will still have 27, for a seven pound difference and the motor (( Internal Combustion Engine ? )) will still operate. Now as the piston, on it's upward stroke is just about to close the exhaust port, you will have 20 psi in the cylinder and the exhaust system up to the butterfly or restriction. That's 20 psi boost. A turbo works like a natural restrictor in the exhaust system and puts out more air pressure on the compressor side in psi than it restricts in the exhaust side. On a four stroke, this exhaust pressure is an unfortunate thing, but on a two stroke it is positively needed. It is said the true boost of a two stroke should be measured between the exhaust port and the turbo because that's the pressure your cylinders will see as the piston closes the exhaust port. There is another advantage to a turbo'ed two stroke. The pressure that is fed through the crankcase before the reeds, that normally would be bumped up 7.5 psi in the crankcase, is much greater than it normally would be. This is probably due to the fact that the outside boost pressure is feeding the crankcase at piston positions that would not normally draw fuel/air into the case. As far as working out all the pressures in all the various places like carbs, crankcase and exhaust, the turbo seems to pretty much take care of all of it naturally. My first try of putting a cover over the exhaust side of the motor (( Internal Combustion Engine ? )) and slapping a turbo on it, then routing the compressor side back to the crankcase with a carb UPSTREAM of the turbo made over double horsepower on the first try on the dyno. The process is simple, but there are a few catches. A carb likes to be drawn through, but it also works to blow through the carb, but either the entire carb must be under boost pressure or at minimum, the top of the float bowls must see boost pressure. There are advantages and disadvantages top both methods. Blowing through the carbs means leaving the carbs in stock location but fuel input pressure must be higher than boost pressure, but all this has been worked out by regulator systems. If you draw through the carbs, this puts the carbs quite a distance from the Engine, so starting and idling suffer a bit. I hope I have gotten the concept of the turbo on a two stroke clarified. I've had quite a few racers say that they still don't get after going through everyway possible to explain it. It seems to be a mental block type thing I guess. So, if you see the concept, welcome to the elite 1%!!!! Dixon

Basically this guy is saying that the turbo wheel and the force needed to spin it causes that back pressure that is needed when the exhaust ports are open. It all makes sense to me, and I have seen turbo sleds on You Tube.

Ok, I'll bite. I might as well spill the beans and throw my plans out there. I have way to many Ideas for my Oddy that I am bound and determined to try them, even if everything goes down if flames.. I picked up several complete 350 engines that I'm modifying in different ways. Why?, why not..

I do have the sno pro 440 sled Engine that at some point will end up in the buggy, but before that, one of the factory engines will be receiving a turbo set up. I have made it my mission since I've been fabricating to learn and experience all I can in regard to turbocharging. I have fabricated full systems on everything from 8 second V6 Buick Grand Nationals to 600 cid pro mod cars. Thrown in the mix has been 800hp 4 cylinders and a couple 4 stroke snowmobiles.

This will be the 1st 2 stroke Engine I'm building a turbo set-up for. I have read and researched till I'm blue in the face and I can see no reason this will not work. I do not care about internet fear mongering or those who have not tried it themselves, all while they ensured things were properly tended to.

It never ceases to amaze me that when I've brought this up (not here) with people I get answers like, Your gonna need to do a bunch of things like run a reference line to the airbox....???? After I finish scratching my head at how or why someone would say this, I just walk away. After all there are much bigger design criteria to address.

I am not by any means claiming to have all the answers, I am saying that I've had great success with previous turbo builds by paying attention to details....Yes Details.. I'm hopeful that I experience some if not much success with this build. The fundamentals will be:

-factory recall size bore 78.5 mm, with water jacketed cylinder and head.
-Aftermarket EFI set up
-stand alone oil delivery and recovery system to supply turbo
-Appropriately sized Intercooler
-Various Engine mods to help support any HP gains
-Appropriately sized turbo

I realize many have tried and failed, that said, others seem to have been very successful. Carburetors can be modified to work in a turbo set up, however I have no desire to use a carburetor in my build. I'm also not looking to make a million horsepower, I may at times be delusional, this isn't one of them. This undertaking is strictly to be able to say, I tried that once...

The build will start where it should, identifying various aspects of the Engine I'm working with and then a fair amount of calculations to find: desired or target boost ratio, air flow requirements for target horsepower, BSF requirements at target HP, resulting injector size, turbo boost map versus operating rpm, etc...and it goes on.

Holy F , I guess I am not the only delusional.
From what I have read and gleened from the info is that they run a non expansion chamber pipe (just a straight pipe). Also the EFI, probably so they can control and guarantee correct fuel supply. Also seen a turbo with ceramic bearings so they didn't need oil but I am suspect on that idea.

One of the things that would be an issue I think, is the double lip seal in the counter balancer area. This seal has no face to butt up against or home position. You can deep set or shallow set this seal. It kind of like a BAZ seal, it can go both ways. Retaining this seal (like BAZ) could be an issue. Maybe glue it in place ?? Making retainer face plates for the other seals no real issue and the seal on the clutch side wouldn't need on as the double lip will retain the pressure in the crankcase.

The crank seals are an area in the motor (( Internal Combustion Engine ? )) that is on the list to explore. The plan calls for exploring the removal of the counter balance shaft altogether and looking at balancing the crank itself. We'll see how that works out. I know it's been done before. Also I will be using the pipe with the expansion chamber and placing the turbo where the silencer normally goes. I still foresee the need to use the resonance pulse to transfer the energy to the turbine. All turbochargers use lubrication one way or the other. A turbo with a ceramic bearing cartridge still needs lube. Some manufactures have designed a self contained setup, ie areocharger. Turbos that have a traditional bearing set up actually depend on a thin film of oil for the turbo shaft to spin on.

food for thought, supercharging 2 strokes is not a new thing, they were doing it in WWII on 2 stroke diesels.
One of the things I would be wondering about is the port timing, I would think as you would be asking the Engine to do something completely different that may be something to consider.
Not sure if using the expansion chamber would be the way to go, you are going to have more back pressure in the pipe than designed for and would the chamber work as designed? Also heat is not the enemy of the exhaust side of the turbo, if I'm not mistaken they normally put them close to the head by design.
I by no means claim to know anything about setting up a turbo, especially on a 2 stroke, I know it can be done and it's good to see someone on the forum doing it, let us know how the process goes, I wish you success!

So, as an experiment, place an exhaust pressure gauge in the expansion chamber of a 2 stroke, how much back pressure do you think is present in NA trim...I ll let someone else answer that. The turbo regardless of placement is a restriction. The real goal is to ultimately set the system up so the exhaust back pressure is equal to or less then the boost signal. When building 4 stroke race set ups, I change not only placement but the entire design of the exhaust system depending on the needed boost needs of the vehicle. WWII plans utilized Paxton centrifugal ball bearing driven superchargers, not super efficient, yet effective. I urge everyone to read the post CO put up....understanding is imperative to the 2 stroke turbo discussion..

Methodical,

You'll want to keep the Engine stock with stock expansion chamber, the Engine will need to breath. Also keep the stinger opening the same size as a smaller opening creates more heat in the Engine. There is a lot I have forgotten when I was playing with a 53 Aerodyne on my Polaris 700 pilot, that said I could never get the bog out of her and ultimately went to the 800 VE Engine in the FL800. The Turbo Doctor (aerodyne in Ogden) kept blaming it on my pipe, I built 5 variations and kept getting closer. Ultimately the playing around with the system lead me to the best pipe to date that Baz is now running. I believe there are several turbo options for 2 smoke sleds still being produced all of which use the stock expansion chamber.

I wish you the best of luck,

Ak

Loving this back from the ded old thread at the moment.
Had a delusional thought -- to keep the turbo spun up I wonder if you could inject raw fuel into the exhaust turbine to keep it spun up and prevent lag ?? It would be so cool to see an oddy on the 1/4 mile baahahahahahaha.

Anyone who has read my previous posts with any intent, will know I love to buy SAE research papers. Researchers spend countless hours and research dollars trying to solve the issues that are at the very genesis of the questions we debate. That said, I freely spend money paying for copies of the rather valuable research. Just so it's out there I've spend several hundred already on research relating to turbo charging 2 strokes. Yes it absolutely positively works. Now, that very discussion grows exponentially with the who, what, when, where and why.

The utilization of an expansion chamber is mandatory. Most believe that the offset in exhaust expansion required to transfer the energy to a turbo and build enough boost in a satisfactory period actually calls for the use of a chamber exceeding the factory or calculation spec'd size for the NA variant of the turbocharged motor (( Internal Combustion Engine ? )). To big a chamber, your efficiency drops and so does your power, to small a chamber and the heat rises uncontrollably and the piston finds ways to piss you off.

Another must have (in my book) is efi. One must eliminate the pulse signal or lack there of, that the turbo induces with supplied atmosphere to the system. Things are no longer adiabatic, they are driven to become an outlyer. I urge people to read CO's post. There is so much actual information in those sentences that its scary. I unfortunately believe most will look past the answers being proffered. They are not all directly stated.

Anti lag philosophies do not work on 2 strokes. The fuel would cool the chamber and result in reduced power..

AKpilot, can you tell us a little more about how you went about changing the pipes and why. What changes to the pipe resulted in what changes to the drivability.. Thank you.

Trying to keep this thread alive as it interests me.
Like methodical said: tell us more about the pipes please.
Also found this on you tube: https://www.youtube.com/watch?v=lj0wWF6nhxU
I know methodical will use EFI but from the video above you can see some of the technical issues with a blow through and the solutions required. Also note the pulse fuel pump issue. Fuel delivery is essential for an oddy.
Below is a picture of my race car and behind me is a turbo motorcycle Engine powered D sports racer. That little bugger was fast. Fast than me and my13B peripheral port rotary or my 12A peripheral port rotary. Note also that my rotary is a two stroke. He would pull me about 7 car lengths on the straight but he was painfully slow in the turns. The real problem was he that always blew up -- every race.

I will post certain information from one of the research document: Turbocharged Spark Ignition Two Stroke Engine.

The bits of information should be a great primers for discussion.

DIFFICULTIES WITH FUEL INJECTION- Electronic fuel injection of a two stroke Engine presents two major technical problems that are not found with four stroke engines: characterizing the effect of the expansion chambers on delivery ratio and dealing with misfires.

Air flow through the Engine is a function of Engine speed, manifold pressure , and tuning effects of the exhaust expansion chambers. These tuning effects are highly dependent on the temperature of gases in the exhaust system due to the effect of temperature on the speed of pressure wave propagation in the expansion chamber. The temperature in the exhaust is dependent on the recent operational history of the Engine. So, a control scheme to electronically fuel inject a two stroke Engine must either take into account the load time history of the Engine, or it must have an alternate method to determine required fuel flow.

This should start the conversation. thoughts on what they re driving at...

That says a few things to me.
1) Delivery ratio says to me that air/fuel ratio may change with lower rpm and any pulses in exhaust. They seem to be worried about that and the amount of the charge will change with in the rpm range.
2) Expansion chambers (different styles of pipe) probably work different at lower rpm than at higher rpm with regards to the amount of air/fuel charge you are going to get.
3) The temperature of the exhaust seems to be a factor as well, according to that statement above. The speed of the pressure wave in that expansion chamber must change if it gets hotter or colder and this would change the amount of air/fuel charge.
4) Misfires ?? Not sure what they are talking about but maybe the air/fuel charge amount will change if there is a misfire at some point. A misfire will also cool down the exhaust and your flow will change. Also if the amount of charge is different then so is the amount of compression and pressure in the combustion chamber.
5) They talk about load time history. That says to me that they are looking at where will this Engine be running at most of the time. What range of rpm.

That's what I am reading into the statement above.
Apparently the exhaust pipe, exhaust temperature and rpm is what it is all about.

Basically they are saying that it is difficult to set the correct amount of fuel injection if everything is constantly changing with regards to the amount of flow. How do you adjust and measure for this constant state of change ??

CO, I am absolutely impressed. There are many paradigms you nailed.

A little more about the subject of the paper. The research team was working with a 4 cylinder two stroke Engine, that would be developed to be a class specific power plant for the speedster class at Bonneville. The Engine was limited in size in order to take advantage of class weight breaks, and the two stroke would be operated at high rpms (well above 10,000 rpm) for extended time. The answer to make horsepower was the addition of the turbo, to move as much air in a controlled manner through the Engine as possible.

One ideology of the research is that when two strokes are operated at high rpms, that fact that the cylinders are fired every revolution coupled with the air flow required to operate at the elevated rpms, cylinder misfires become common. (nukems high rpm beastie motor (( Internal Combustion Engine ? )) with 2 plugs comes to mind) On a single cylinder Engine the misfire can be brought under control readily. The case is not similar with multiple cylinder two strokes.

These facets become increasingly and understandably important when utilizing efi on a two stroke. The authors wanted to use injection to aid in addressing the known challenges of using a turbo on the two stroke. They discuss how Honda R&D identified and addressed this challenge when designing there moto GP race program.

Here is some verbiage being attributed to the Honda race program:
Honda R&D has identified this problem and addresses the change in volumetric efficiency by measuring exhaust gas temperature and mapping the change in volumetric efficiency versus exhaust gas temperature at varying Engine speeds for the fuel injection scheme in their naturally aspirated Grand Prix racing motorcycle. The Honda system uses Engine speed and throttle position to determine a basic pulse width from a map in the controller. Modifiers for exhaust gas temp, manifold pressure, ambient air density coolant temp, and misfiring conditions add or subtract to the basic pulse width. The Honda system uses a load cell washer under the spark plug on each cylinder to sense the misfire . If an Engine misfires under a high load and Engine speed the temperature in the exhaust pipe will decrease and reduce the scavenging effect of the pipe, thus lowering the airflow to the misfiring cylinder. The Honda system was designed to identify the misfiring cylinder and adjust the fuel delivered to that cylinder to maintain the proper air fuel ratio so the cylinder will start firing again.


There is a lot going on here. The challenges the exist in the fundamental operation of a two stroke Engine seems to be compounded when pushing them to the limit. Introduce a power adder such as a turbo charger which is all or partially driven by energy changes (heat, pulse, etc and not totally agreed on by everyone) in the system, and common events in the combustion process are amplified exponentially. And just think, we are only finding a place to start this conversation.


I'm keeping this discussion semi loose as I really dislike typing so much....

Boy, do I have information to throw out there regarding this one....

Here is a video that most of the old timers will remember - posted 9 years ago. Really shows how bad the lag was, but also shows what can be had. In the video the Pilot had 28" mudlites vs 26 mudlites with the 800VES Engine. When she was on the boost 6-8 psi I was able to pull the front up in soft sand, with the 800 or the Nytro I need wet heavier sand and from a stand still. Goes to show the 700 turbo was making some power, if only right?

https://www.youtube.com/watch?v=thnG1ZILsgY

I had to build pipes as I put a Polaris snowmobile Engine in the Pilot. I first started out with dual twin pipes, I think there is a picture in the Akpilot build thread fully modified Pilot. I had good success on the twin pipes and not knowing what to expect from the 700 in a heavier vehicle, I needed more HP, with running oil Uni filters as opposed to open airbox of the sled I decided to purchase a turbo kit from Aerodyne specifically for the Polaris 700 Engine. I needed to do no engineering to the system, except making a stock pipe fit the pilot constraints.

1st. Pipe, I was more worried about getting it to fit the chassis and size and length was secondary. So I built it but needed to take 6" out of the expansion chamber to fit in the frame and up into the turbo. Well the poor Engine could not get out of it own shadow, I don't care if I had a mile it would not produce any boost. It would however run on N/A but was a big dog, nothing even close to the twin pipes I made.

2nd Pipe, I put the 6" back in and it made a large difference, the pipe stuck out the back of the frame but it did work better. It was not as good as the twin pipes but close. still had lots of lag. I cant remember if the video was shot with pipe version 2 or 3.

Pipes 3 & 4 were playing around with the Head pipe, the sharp bends - going down out of the Y pipe, then 180 degree turn and then up over the clutch. I talked to Crank shop in NY where I purchased the "twin pipe Kit" and they informed me the head pipe is very important to getting right, so I made two versions one larger in diameter then the other one. I couldn't tell the difference between 3 & 4 as I canabalized them, but still not there.

On the last pipe - the one Baz has on the FL800, I got away from my Billy-Bob pipe making and purchased a M7/F7 pipe off Ebay. I then mapped out the stock pipe exactly and made this pipe fit those measurements. I took the stock pipe and sectioned it off in 4 sections and drew lines length wise down the sides of the pipe, at 0 degrees (straight up) 90 degrees, 180 degrees and 270 degrees. Then I made a mark at every inch from the head pipe to the stinger and with a string measured each circumference. I collapsed and expanded each measurement to exactly match the stock pipe but configured it to match the stock pipe, I even had to modify the bottom of the gas tank to fit the new pipe. Was this right? Not sure as the stock pipe made a lazy 180 degree turn to the expansion chamber and the M7/F7 makes a hard turn and thus fatter in the head pipe section. Engine design, port size, ect. dictates how the pipe is to be constructed and with the M7/F7 Engine close to the Polaris maybe I should have made the head section fatter instead of the size of the Lazy Polaris - who knows as I went away from the turbo and purchased the Polaris VES 800 Engine instead. I did put the 700 Engine back in the sled that spring and ran the turbo with a stock 700 pipe from a 2003 VES Engine (not the '97 Engine) and was less than pleased with the results on the only time I took the turbo sled out. I had planed on playing with it in the future but the 800 Engine with pipe 5 worked so well I didn't build any more and went on to the Nytro Pilot build.

Don't know if any of this helps or not but at one time I too was thinking IF I could sort out the turbo then try a smaller turbo and put on a friends stock Pilot as he was never going to go to my length for more HP, but wanted more than the stock Pilot.

My whole problem was stalling the turbo, the carbs worked great under pressure and no issues at all it was just the lag. I also remember thinking that the clutches were working against me as well. The heavier weights the turbo needed also made for lazy revs. If I lightened up the primary clutch it would rev faster and lag would not be as bad, then when boost would come on I would over rev. I tried "tucking" the weight but that didn't help. I had the thought of notching the weights but as bad as the lag was and as big of a notch I needed, I was asking for trouble.

From memory my setup:

1. 53 series Aerodyne turbo, self oiling system. I purchased the turbo second hand but know the turbo was in top shape. I needed to "clock" the inlet and outlet so I took it apart and clocked it to fit the pilot. Then I flew down to Ogden Ut and personally went to see the turbo doc and to through the unit and pick up anything I was lacking (my brother lives in SLC).

2. Electric fuel pump
3. fuel regulator
4. 3 each Power Jets - basically a external needle and seat, each carb and one into charge tube. Think dial-a-jet but better IMO.
5. electric solenoid to actuate 3rd power jet only on boost.
6. turbo air box and carbs vent into airbox. When carbs are on boost so is your float bowl and visa-versa.
7. blow off valve, No need for a waste gate as Aerodyne is a variable vein turbo.

Whether you use carbs or EFI the power programer will adj the fuel requirements as boost come in. I currently have a turbo on the Apex powered Wildcat and that's how it works. The carbs change with boost pressure as well - basically the carbs, fuel system don't know or care as they see the same pressure as the Engine sees.

I hope this helps,

Ak

HOLY F you guys
That's a lot of fooling around.

I just had a thought (sometimes that's bad), but it would only work on a 1/4 mile car in my opinion.
What if you had a three blade turbine ?? What I mean is a turbo with three impellers on the same shaft. Now this can be handled in several ways but I am thinking of only one specific idea right now actually. The third turbine would be spun by high pressure compressed gas. This gas would be released by a solenoid. It would be activated by electronics when required. This would cause an over boost when needed for air/fuel mix and more power. The reason this would work can be explained easily. Ever try to spin a bearing with compressed air ?? Spins pretty damn fast don't it ?? Nozzle size, impeller size, pressure would all require some testing.
P.S : I am not a turbo guy. Never worked on one so maybe this sounds retarded.

Yea that was a lot of F-ing around alright, I even tried putting V-Force reeds in the air box to help spool up the turbo quicker - no go. With the 800 working so well and instant throttle response is kind of why I went away from the turbo. That said on the Wildcat I don't really notice any lag. In the sled world Yamaha's have been supercharged & turbo'd for years and finally Yamaha came out with a OEM turbo for them and Arctic cat. I've been on turbos 4-strokes and lag is pretty much a non-issue but Yamaha takes no lag to a new level.


http://www.amsnow.com/news/dyno-tests/2 ... -dyno-test

Ak