I have them on my XLT and absolutely love them. I was able to drop my main jet size for 20F down three sizes and operate safely in temps ranging from -15F to 40F crisply and with an improvement in fuel mileage. You can get away without EGT guages when tuning the dial-a-jets, just follow the instructions in the book and don't deviate from them. The same cannot be said about UFO's. To get the full benefit out of UFO's safely you need to have EGT's.

http://www.mtaonline.net/~mhbs/Moorefamily/snowmobile1.html

 

i've tried the dial a jet but it did'n seem to work for me.i think i got a faulty one because i've tried it on 2 different carbs with no gains,i fallowed the instruction ,and i even have EGT gauges and never noticed a difference in the temps while i adjust the damn thing.but every one else has had good luck with them.this one probably just has some KA KA in it.i'm going to try using an air hose on it to create a false pressure drop tp see if it's working. i'm going to try the tempa flow i think this year.

motor head

 

Nashoba- Your only talking $140 bucks for a triple, and they claim a HUGE performance improvement. I'm planning on getting a set myself. I had a bad experience on the Canadian border north of Rangeley. The altitude change killed me.

Frank- I've seen your site, and I know you tool around some pretty tall places. How did you tune yours? I'm in maine also and if I had to guess I would say we average 2500 ft with the tall places going over 4500 (that's when I had trouble). Do you just pick a mid point (altitude wise)and set that as your mid point (on the dial a jet)?

 

hey M38A1,where abouts in maine do you live?i live in waterboro. i like the dial a jets for one reason they reintroduce a better atomized mixture of fuel to the engine,the thing i don't care for is if you want to ajust it you have to stop,lift the hood and turn.i'm not lazy but when you are riding with friends its a pain. the tempa flow is produced by holtzman engineering and can be mounted on the handle bars,it has a dial and can be turned with your thumb;if you mount it in the right place.plus if you go through hugh elevation changes they sell inserts that go in the vent line. the real plus is you only have to drill into one carb vs drilling all three carbs! you decide,they are both great products and accomplish the same end result,adjustability!
P.S. you only have to drill one carb because it works off from float bowl pressure,the other carb vents get connected to it.

motor head

 

Actually Matt, most of those photos were taken at about 3000', except for a couple near 6500-7000'. That is the highest altitude I'll ever get to. Most of my riding takes place at 500'-3500' . Alaskan's get to enjoy low altitude deep powder that few other places in the world get to. The low altitude translates to big horsepower if you've got an 800, compared to an 800 at 7000 ' in the Rockies.

You will not feel any huge performance gains from dial-a-jets if you do not ride in areas with big temp or altitude changes. All I use it for is a lifejacket and a time saver. I hate having to rejet. I have had days where it was -10F at my front door and within an hour I am at 3500' and 30F. That would definately necessitate a jet size or two. All I do is flip the cowling, turn three screws and I'm off. I have managed to ride with four main jet sizes smaller than recommended in all conditions. This translates to more throttle response and better fuel mileage.

I dialed mine in on a 0degF day and at 500' altitude on a local lake. I set mine for the second from the lowest setting at this temp and altitude. Reading the plugs I was able to lower my main jets to 150's on an XLT with 34mm carbs. It allowed me enough adjustment this season to ride from -15F (as cold as I like to ride) to 40F and up to altitudes of 5000' without a noticeable change in performance. After 5000' at 30F I began to loose H.P. and ran extremely rich. Since I was at this altitude for only an hour or so I didn't bother rejetting. That was the only time the dial-a-jets didn't have enough range to keep up. But, with 2000 miles of riding this year, I think that was pretty good.

After a top end tear down tonight I may have changed my opinion a bit. I like to yank off the cylinders every once in a while just to see how things are going inside. About every 2000 miles, or at least once a season. The new Wiseco pistons I installed last winter showed signs of over heating slightly underneath the piston crown. However, I had good piston wash and ideal carbon build up on the top of the piston, so I think I may have pushed it too hard before getting it good and warmed up ( had some mild cold seize scuffing on the intake side). I really think it happened when I rode last year at -20F and forgot to richen the dial-a-jets. No seizure, but I got close. Which sums up the curse of dial-a-jets...if you forget to adjust them and it's too cold you will end up with a lean condition and a hot engine. BUT..the way they are designed they dump fuel when they sense a lean condition and that's what probably saved my butt. Ring gap and cylinders were excellent after 1500 miles of hammer down riding, so I think the Wiseco's are all right, or at least not as much junk as some people think. Definately more carbon build up on the exhaust ports with Torco synthetic as compared to Amsoil, so I may switch back.

I'm going to pipe it this year so I really get to challenge those dial-a-jets.

http://www.mtaonline.net/~mhbs/Moorefamily/snowmobile1.html

 

this reply is about the wiseco pistons. i think they are the best,if used properly.they're alot stonger,resist detonation better,and lighter compared to a stock piston.when the piston does fail its usually the riders fault.forged pistons need to be FULLY warmed up before you ride the sled or you will get cold seizer ,scuffing,and possibly a broken ringland,because when its cold it will rock back and forth in its bore until it fully expands and stablizes.these are racing pistons and not meant for impatiant people who can't let their sled warm up fully(i'm usually one of these people,but i'm tring to change my ways)
so if used correctly they're better in every respect.
i've got forged pistons in my 400 chevy small block and its a pain to let the damn thing warm up for 5-10 min before i drive it,but its definatly worth it because this motor puts out some very good power and she hasn't failed me yet!

motor head

 

Sldhd- Windham.

Frank- Thank you. You're right the photos are deceiving! You basically ride in the same or similar conditions I do. Maybe a bit less altitude. That having been said your post was very helpful. We experience alot of temp shift here. Below zero in the AM, but if the changes to out of the south and it's sunny, it's no problem for us to see 45 by early afternoon.

 

Sldhd- What kills me is lunch time. I sit for a half hour and eat, look at my pics I eat alot. Then all the sudden every one takes off and I do too with a cold sled.NOT THIS SEASON. It costs too much. I'm sure that's where the little scuffing I have comes from, because when I start out I start my sled in my slippers then put on all my gear,(it's a blessing to ride from your front door), that allows for at least a 15min warmup.

http://www.mtaonline.net/~mhbs/Moorefamily/snowmobile1.html

 

doesn't it stink when you know you got good stuff in your sled but your friends don't want to wait intil its the right time for you to move! we always pay the price one way ar another!

motor head

 

Never tried the dial ajets but for what you are trying a tempa flow would work great. It is fully automatic once you get it set. The vari flow from holtzman is the one with the adjuster on the handle bars, works like a dialajet just at your finger tips. Try www.holtzmaneng.com. Maxdlx