Can the timing be re-programed at the box or must it be done at the trigger coil? I'am looking at making a 26 thousand's increase. Started out an Flll 800 now a MachZ with all changes to Z specs. except timing[0.76 Flll] to [.102 Mach]. http://www.snowmobileworld-s2.com/forums/iB_html/non-cgi/emoticons/withstupid.gif

mkadoo... Do you mean 2.6 degrees? I think you mean .026".

I think you have to move the trigger.

I was thinking..26 degrees is huge...

Guys, I need to move it *from 0.76 to .102 that's 0.26 thousand's not degrees [my fault, I will edit the first post] The book says only can be done by the mpem [little black box on the air box]. This figure is by using a dial indicator in the mag piston off T.D.C. like the old way. Thing that puzzles me is the book shows 3 degrees max by going with the mpem? I think what their saying is if it's off UP TO 3 degrees the adjustment is done at the box. I would think someone has done this, as I'am not the only one in the world that went from single to triple pipes...

This is weird, I bet no one ever changes their timing when going with more than one pipe! Just think of the power gain they COULD have! Must be something to it or the manufactures would'nt do it! look at any shop manual for any stock sled that offered one-two or three pipes of the same CC engine and the timing *always advances with the increased number of pipes......

What you need to do is get the factory service manual, that will show you the procedure to check the engine timing. You will need to check your work when done. first get to the pickup & remove the silicone around the sensor then see how far it will move. You most likely have to slot the holes slightly to get enough advance. now check timing again if still not there, get your dealer to do more in the MPEM. also check the air gap on the sensor as this can affect ignition performance. I prefer to leave the MPEM some where near 0 change & use the pickup instead.

I've got a 99 f3 800 and bought a new MPEM module from the skidoo race dept (via my dealer) when I put jaws pipes on it. I had to bump up the rev limiter. BTW the timing spec was the same in '99 for the F3-8 and MachZ. I gather you have a 2000 F3-8 (the timing was different)

I guess you can also give the race dept a new timing spec.

I've never touched the trigger coil but thought of doing it for drag races. *I'd be interested to hear how that turns out.

MXZ900, I have the service manual on my sled and it shows the procedure but requires a lot of expensive equipment to make the change. You see, I took my sled to my dealer and had the timing change done but cannot fully trust him. I was there when he performed the change [only took 10 minutes] and he said it was changed to Z specs. but have my doughts after reading the manual. As I posted eariler, the book shows only up to max of 3 degrees unless I'am reading it wrong.
I may be confusing degrees with thousand's? How many degrees = thousand's? When using a dial indicator you do it in thousand's but when using a lap top you do it in degrees?http://www.snowmobileworld-s2.com/forums/iB_html/non-cgi/emoticons/confused.gif

Mikadoo
If your sled is any newer than 98 you have to set the timing
at your dealer on the computer as the pickup is non adjustable.If it is 98 or later you can adjust it as usual,dial indicator and set to about .086 before tdc. that is the setting
for Jaws triple pipes i assume thats what you have,.102seems way advanced to me best double check with pipe manufacturer. * * * * *good luck grey goat

so how do you change the timing? I have a 98 mach z with jaws pipes and never change the timing, But I have been having problems getting it to hold r.p.m on top end.Do you think that would help?

Boomer
You have to set the timing to .083b.t.c,you also have to change the needle tubes in the carbs and change jetting to
the 440 range,the needle tubes are 04' needle set at 4 and air screws 4 turns out.Put in threaded set screws in clutch
2 in each pin a green pink spring 286 ramps,also a 44 degree
helix this set up is good in the mountains to just bring your jetting down.These are all Jaws specs. and i used them on mine and this thing rocks.Boomer I live about 100 km south of you. *Grey goat

Setting the MPEM can only be up to 3 degrees advanced, unless you move trigger coil. The 3 degrees should be fine with pipes and 91 octane fuel. The dealers should set the MPEM programmer to # 2 to attain the 3 degree advancement. I usually redo it my self to make sure it wasn't screwed up. *It can be set from -4 to 3 degrees advanced with mpem. This works on twins too.

Thanks guys, I called Chuck Walters [Mr. Skidoo himself] at twin lakes marina and got the low down on setting the timing.
Yes on the 99 and up you can only set with the MPEM. I'am not going to get into details as it is quite lenghtly. The old days of slotting out the trigger coil are over!

Greygoat, unless my manual has a mis-print a stock 2000 MachZ is .102 BTDC quite a bit higher than the older doo's.
This sled has stock pipes not jaws, I would never blow $1000.00 on pipes!

yes mikadoo you have to move the trigger to go from
.076 to.102 as that is your static timming for the mpem
to start its baseline timing curve to work from,then you also
get the mpem reprogrammed to use the mach z curve in
place of what you had to begin with.

You can machine your case to accept a 1997 stator and pick-up and use a 97 cdi box. Set the timing were ever you like. You would lose the dess.