Have i mentioned how much I love our 998's?

[yamamarc]

My current set up
2019 zr9000
1 1/4 track 196 studs (1.450)
snow trackers carbides
Hurricane header/Performance muffler bundle(240/270/300)
-Hurricane header with extra clearance
-Hurricane stock replica performance muffler
- 3 bar map sensor
- turbosmart bov
- stm clutch weights
- i left my 21/38 gears in for now but plan to for back to 24/50 with a 1.5 track


New this season
-Closed loop
-Gap ram air
- stm primary clutches (newly redesigned clutch this season)
- studded out edge of track
- mainway solutions control are greasable bushings and rear skid mount greasable bushings. I also have the bell housing upgrade to get ride of steering play from Val but i haven't installed it yet.
- sled wrap
- removable hard case for storage
- new bushing in top gear
- all skf bearings
- homemade tunnel hose protectors
- homemade rear skid mount reinforcements


This sled is amazing just love this motor and the chassis!!! We got out on some nice and bad trails today and my sled performed amazing!!!! I was getting discouraged trying to get my new stm primary to work properly with my oem team secondary the last few weeks. Last night I decided to put the stock helix and spring in and hope it was good for my ride today...
Ran the 300 tune and gave er a good go on lake Wanapetie. The lake was hard packed and smooth like a highway and got 19.4 lbs at 9050rpm with the header tune. This thing was on fire! Today it was the first time i ever hung the skis from cruising at 100mph and stabbing the throttle.... WOOH WHAT A RUSH
Not sure what my top speed was but it felt very fast...lol

The closed loop imo is worth it! Nice to see afr and can really find that lean cruising rpm when you need fuel economy imo! On some of the rougher trails my afr were hovering 13-14 .
The sled just felt crisp and really stretched my arms..lol

intake temps with gap ram air was 10 f on lake and 13 f in trail
weather temp was -19 in morning and -13 c with a cold wind in afternoon
Engine temp 168-170
Only have one complaint!! After adding studs to outer edge of track she really vibrates. I actually thought I lost a driveshaft bearing..but all ok.. it vibrated enough that the nut on the positive terminal on battery came loose. Came to start the sled after stopping and nothing dash never lite up, my first thought frozen relay. I took seat off and battery connection was loose.

It's a freeken vibrating rocket...lol

 

[KnappAttack]

Are you logging at all? What is your A/F on the 300 tune with a header at that boost level? Reason I ask is I'm completely out of injector at +15F on the 300 tune with the stock manifold as the closed loop trying to add 15% fuel and maxed out. It flashes the dash after seconds of WFO if I try the 300, my AF is 12.3-12.4. But man alive my 270 is fantastic anyway, I don't even need the 300 really. It now pulls more weight & helix and more RPM than my 300 ever did before using the XS825 belt too. I think I'm close to maxing the injectors on the 270 tune as the closed loop is adding over 5% more fuel and getting darn close to 11.9-12:1 on the logs. I just keep adding weight and helix to it to bring the RPM down.

I think now that my 3" VF muffler is just adding that much more HP, I bet it is. I'm also running 45 lbs key on for fuel pressure, so about 1.5 lbs more than normal and with the big pump too. I may need to bump that up more.

I am very happy now this season with this sled. Only took 3-4 seasons to really perfect it and get it to the point that rollers stay in the clutch, belts stay on the clutches and chain case stays together without worry. Fantastic machine! Just rips to 130+ in no time at all on the trail! I can finally say its better HP wise than my old Apex trail turbo that squeaked over 150HP to the track. Such a terrific ride and great handling machine. Yep, it's a keeper.

 

[DMCTurbo]

Are you logging at all? What is your A/F on the 300 tune with a header at that boost level? Reason I ask is I'm completely out of injector at +15F on the 300 tune with the stock manifold as the closed loop trying to add 15% fuel and maxed out. It flashes the dash after seconds of WFO if I try the 300, my AF is 12.3-12.4. But man alive my 270 is fantastic anyway, I don't even need the 300 really. It now pulls more weight & helix and more RPM than my 300 ever did before using the XS825 belt too. I think I'm close to maxing the injectors on the 270 tune as the closed loop is adding over 5% more fuel and getting darn close to 11.9-12:1 on the logs. I just keep adding weight and helix to it to bring the RPM down.

I think now that my 3" VF muffler is just adding that much more HP, I bet it is. I'm also running 45 lbs key on for fuel pressure, so about 1.5 lbs more than normal and with the big pump too. I may need to bump that up more.

I am very happy now this season with this sled. Only took 3-4 seasons to really perfect it and get it to the point that rollers stay in the clutch, belts stay on the clutches and chain case stays together without worry. Fantastic machine! Just rips to 130+ in no time at all on the trail! I can finally say its better HP wise than my old Apex trail turbo that squeaked over 150HP to the track. Such a terrific ride and great handling machine. Yep, it's a keeper.

So Mike you had to add weight with the closed loop? I've been waiting for feedback on the closed loop. Do you recommend it?

 

[yamamarc]

Are you logging at all? What is your A/F on the 300 tune with a header at that boost level? Reason I ask is I'm completely out of injector at +15F on the 300 tune with the stock manifold as the closed loop trying to add 15% fuel and maxed out. It flashes the dash after seconds of WFO if I try the 300, my AF is 12.3-12.4. But man alive my 270 is fantastic anyway, I don't even need the 300 really. It now pulls more weight & helix and more RPM than my 300 ever did before using the XS825 belt too. I think I'm close to maxing the injectors on the 270 tune as the closed loop is adding over 5% more fuel and getting darn close to 11.9-12:1 on the logs. I just keep adding weight and helix to it to bring the RPM down.

I think now that my 3" VF muffler is just adding that much more HP, I bet it is. I'm also running 45 lbs key on for fuel pressure, so about 1.5 lbs more than normal and with the big pump too. I may need to bump that up more.

I am very happy now this season with this sled. Only took 3-4 seasons to really perfect it and get it to the point that rollers stay in the clutch, belts stay on the clutches and chain case stays together without worry. Fantastic machine! Just rips to 130+ in no time at all on the trail! I can finally say its better HP wise than my old Apex trail turbo that squeaked over 150HP to the track.

Unfortunately I didn't log this run i.had to lend my flasher out for a.few days!! I will be definitely logging once I get it back..
After today's ride I feel I have it set up pretty good paired the stm primary with team secondary. I had the drill and tap the secondary for a belt deflection adjuster.
as for stm weights at first I hated them but now after changing weights around from tip to heel multiple times I really got a good feel on how it reacts. I am really liking the tunability.
Just need patients..lol

 

[sideshowBob]

I agree with how great these sleds are.
I have not even run my sled on the 300 tune this year and only once or twice on the 270 for a short boost.
I find the 240 perfect for my riding style and the fuel mileage has been great with the closed loop ect.
IMO:
The sled looks fantastic, handles great, and runs perfect.

 

[1nc 2000]

I agree with you guys, my sled just flies on the 300ss header tune.
I did a ton of updates this year and can't be happier!

 

[yamamarc]

I agree with you guys, my sled just flies on the 300ss header tune.
I did a ton of updates this year and can't be happier!

Same here I added stm clutch, ram air , more studs and closed loop and it definitely feel stronger then last season..(hook up with 196 sharpened studs is wicked
Was happy I had 0 belt failures when we rode.
I left in on the 300tune most of the day and did countless wot pull on lakes and ran hard in trails..

 

[KnappAttack]

So Mike you had to add weight with the closed loop? I've been waiting for feedback on the closed loop. Do you recommend it?

I don't believe the closed loop necessarily added any power in my case, I do however think it adjusted nicely for the power the 3" muffler I have added. I have also gone back to heavy duty spring pressure in the secondary, no float in the secondary, more primary weight and more helix. I was going down the correct avenue all along by going to heavy secondary springs and IMO the XS825 needs that pressure too as it gets a few miles on it. I was going lighter and lighter and ended up too light. I was trying to save the rollers in the primary, but since I got rid of the sticking winder primary I have no roller and bushing wear any longer. So back to a heavy primary and secondary setup that bites the belt like it should.

One thing I just learned is the new V2 Dalton is much more stout than the old version also, its right up there with the Cat White and black/lime on my drill press scale. I'm throwing away all the V1 springs and will not messing with them any more. V2 is a completely different spring than the old V1 on my drill press scale. So using the new B/O or Cat white or black/lime, all good secondary springs with good pressure on the drill press scale.

It seems like many of us are finally getting these things setup and rocking like they should have been all along for trail use. My sled was always quick in the bottom and mid, but never ran the speed I thought it should, after a bunch of changes everywhere, it now finally has the speed to go with the violent bottom and mid, and it has it one whole tune level lower than I used to run on the trail. My 270 is quicker and faster than I ever was on the 300 before! I'm really pleased with the power output now. It will go out and run over 130 MPH at will on the trail with my big shield on it! I did do some things I will keep to myself due to the competition that reads these forums that have to run against. I do ride with a bunch of other racers after all, so keeping some speed secrets to myself and not disclosing. LOL!

 

[yamamarc]

I don't believe the closed loop necessarily added any power in my case, I do however think it adjusted nicely for the power the 3" muffler I have added. I have also gone back to heavy duty spring pressure in the secondary, no float in the secondary, more primary weight and more helix. I was going down the correct avenue all along by going to heavy secondary springs and IMO the XS825 needs that pressure too as it gets a few miles on it. I was going lighter and lighter and ended up too light. I was trying to save the rollers in the primary, but since I got rid of the sticking winder primary I have no roller and bushing wear any longer. So back to a heavy primary and secondary setup that bites the belt like it should.

One thing I just learned is the new V2 Dalton is much more stout than the old version also, its right up there with the Cat White and black/lime on my drill press scale. I'm throwing away all the V1 springs and will not messing with them any more. V2 is a completely different spring than the old V1 on my drill press scale. So using the new B/O or Cat white or black/lime, all good secondary springs with good pressure on the drill press scale.

It seems like many of us are finally getting these things setup and rocking like they should have been all along for trail use. My sled was always quick in the bottom and mid, but never ran the speed I thought it should, after a bunch of changes everywhere, it now finally has the speed to go with the violent bottom and mid, and it has it one whole tune level lower than I used to run on the trail. My 270 is quicker and faster than I ever was on the 300 before! I'm really pleased with the power output now. It will go out and run over 130 MPH at will on the trail with my big shield on it! I did do some things I will keep to myself due to the competition that reads these forums that have to run against. I do ride with a bunch of other racers after all, so keeping some speed secrets to myself and not disclosing. LOL!

I agree Mike the closed loop probably doesn't add power but it definitely keep the motor running efficient...imo
I know my sled never ran this well before but I did do many changes this season!! Also notice no black soot on side panel after 400km
I did get a few backfires when launching from a dead stop but could fuel related. I had 1/3 of last years fuel in it then top up with 93 and 1/2 a bottle of vp octainium
Once my flasher is back ill start logging

 

[WinderFab]

Sorry Marc for stealing your flasher ..

 

[number1kyster]

I like my 998. But I need to stop visiting this site. Now every time I ride it I'm paranoid that I'll blow a clutch, belt, head gasket, top gear, or that I'll start losing RPM.

I seriously need to learn to just get out and ride and not worry about it.

 

[KnappAttack]

I was out and put on 110 miles today. It was anywhere from -8F to -4F today. Very cold intake temps! I could not run on the 270 tune or the dash would flash deto even with a boat load of booster in it. I'm none too impressed with Klotz booster to be quite honest. Injectors are maxed and boost just too high for the conditions. All I could do is run the 240 tune and it was at 12.2 A/F at times too if the intake was at low single digits above F. Boost on the 240 tune was a bit over normal 270 levels and was over reving the 270 clutching! I'm sure because I'm running the CAI and 3" muffler and its flowing way to well and making good power.

Thank goodness for the multi-map! No wonder we are starting to see some of these machines blowing up. Can't keep boost in check with the cold temps and large mufflers and different mods. It'd be great if the ECU worked like it's supposed to and control the boost accurately in any temp.

 

[sideshowBob]

I was out and put on 110 miles today. It was anywhere from -8F to -4F today. Very cold intake temps! I could not run on the 270 tune or the dash would flash deto even with a boat load of booster in it. I'm none too impressed with Klotz booster to be quite honest. Injectors are maxed and boost just too high for the conditions. All I could do is run the 240 tune and it was at 12.2 A/F at times too if the intake was at low single digits above F. Boost on the 240 tune was a bit over normal 270 levels and was over reving the 270 clutching! I'm sure because I'm running the CAI and 3" muffler and its flowing way to well and making good power.

Thank goodness for the multi-map! No wonder we are starting to see some of these machines blowing up. Can't keep boost in check with the cold temps and large mufflers and different mods. It'd be great if the ECU worked like it's supposed to and control the boost accurately in any temp.

Mike I couldn't agree more. We are in a cold freeze here in NWO like we haven't seen since the 70's.[-35c or -31F]...LOL it was just like this when I ran the 1975 I500 on my 340S John Deer! Its the main reason I have been running nothing but my 240SS PM tune. Also I have tried all the Octane boosters over the years but other then 100LL Av gas ,or c14 race fuel ,Torco for me has been the only Octane boost that seems to work for my high perf/boosted sleds. My common sense has prevented me from even trying my 270 or 300 tunes in these cold high atmospheric pressure conditions.

 

[KnappAttack]

Mike I couldn't agree more. We are in a cold freeze here in NWO like we haven't seen since the 70's.[-35c or -31F]...LOL it was just like this when I ran the 1975 I500 on my 340S John Deer! Its the main reason I have been running nothing but my 240SS PM tune. Also I have tried all the Octane boosters over the years but other then 100LL Av gas ,or c14 race fuel ,Torco for me has been the only Octane boost that seems to work for my high perf/boosted sleds. My common sense has prevented me from even trying my 270 or 300 tunes in these cold high atmospheric pressure conditions.

Torco is decent, I used to run Dragon Race Fuel Concentrate which worked really well, but not sure they make it anymore, maybe I'll try calling them to see if its still available.

AV gas will zap your power, its not good fuel for a boosted snowmobile. Ask Tommcat how it works on the dyno, big power losses using it. 270 seems fine if the intake temps are in the teems or 20's on mine, but in the single digits no way, I have to use the 240 and even that is pushing it on my 3" muffler, over boosting and out of injector at WFO. Guess it wasn't designed to run on a 3" muffler at those cold temps.

 

[NYTurbo]

A bunch of locals have gone to the Dalton white.