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one fast 98 mach-z
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Discussion Starter · #1 ·
i did a search in this forum and found nothing on this subject

for dead stop lake drag racing on hard packed snow

any suggestions

because i am 255 lbs plus a leather suit

fully studded

so we have front shocks coil spring tension adjustment

front skid shock coil spring tension adjustment

aft skid spring adjustment

than riding position

some say sit on seat and slide back as far as you can

others say stand up with feet on aft part of running board
 

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Is it still the OEM SC-10 or did you upgrade to 10 II or 10 III?

If it's still the OG skid, the ACM will control the majority of LOAD TRANSFER to the track. Some go hog wild and remove the nut all the way but that's a bad deal IMO. There's a measurable amount of time the sled will remain still as it rolls back onto the track instead of MOVING FORWARD. I like the ACM to be as far out as possible without the threads losing contact with the nylon portion of the lock nut. My best launches were always done with me sitting on the sled. Yes I was as far back as could be, but I have another preceived 'enemy' in my skid, Boivin ETS bars. My set up for drags was ACM like I said, all springs full soft except the center spring on 1 above full soft (front of the skid). Even with an aggressive 240 stud track (some were chisels) it still spun just a bit. Even with a bit of spin I was long gone while several opponents were rolling back on their tracks. I don't know the measure of time (ET) lost but you can see it very clearly.

In your case, ACM turned out as I said, rear springs full soft, ski springs full soft, center up 1 from full soft. Sit back on the sled but be ready to raise yourself over the bars/windshield to counter excessive lift at the skis. I've had to do that occasionally when conditions were near perfection. Skis in the air looks kool, but nothing is free. It costs ET, and ET is what wins drag races.
 

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Sit up on the tank or at least a neutral forward position. Good weight transfer while keeping the track flat. I've never understood why some hang their rear ends way out behind the seat while standing up.
 

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one fast 98 mach-z
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Discussion Starter · #4 ·
my suspension is stock so sc-10

the front ski shocks , do you put them soft all the way ?

for track tension , do you go a little tighter than factory setting ? or looser ?
 

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one fast 98 mach-z
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Discussion Starter · #5 ·
Sit up on the tank or at least a neutra forward position. Good weight transfer while keeping the track flat. I've never understood why some hang their rear ends way out behind the seat while standing up.
the more your body is aft , the more weight is on the track and less on the skies

just like a two wheel drive pickup in the snow, the more weight in the back , the better the tracksion
 

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the more your body is aft , the more weight is on the track and less on the skies

just like a two wheel drive pickup in the snow, the more weight in the back , the better the tracksion
The more you'll have weight over the rear axle of the skid creating a pivot point reducing the contact area of the track to the ground. JMO
 
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I agree with maluchm, zero weight transfer to keep track on the ice put your weight as far forward as you can. Don't hammer the throttle with carbide studs.
 

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Tighten limiter straps a bit. Makes major difference. I like to think of it as a boat getting on to plane.. The faster it gets on plane, the quicker it will get goin
 

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the more your body is aft , the more weight is on the track and less on the skies

just like a two wheel drive pickup in the snow, the more weight in the back , the better the tracksion
It's not that simple. It may seem that way looking at it from a drag racing perspective, or as you stated, like a wheeled vehicle. It isn't. There's different forces in play. It's not like a tire on a drive axle. The skid frame is forced down upon accelleration. The ACM controls that down force and applys more or less depending on where it's set up to STOP the total down force of the skid. This why I said be ready to move your weight forward when conditions are near perfect. The down force translates to LIFT on the rest of the sled. By the time the low ratio of the clutch system and the drive ratio of the chaincase and track have multiplied the engine's available TQ you're looking at somewhere north of 650lbft of WORK being put to use. More than enough to lift the whole sled and the rider in a glorious "skillie" sure to please a crowd of onlookers. Sadly it doesn't please the time slip with low ETs.
 

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one fast 98 mach-z
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Discussion Starter · #11 ·
how about the front shocks spring tension ? stiff or soft on the coil spring preload

I assume a lower front end { soft spring tension } is better , but I will ask advice

I understand lower the rear suspension springs to soft all the way , then the front skid spring tighten one click
 

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Rear suspension set all the way stiff! Soft will ride wheelies, keep taking your limiter straps up till you start losing traction. Keep the front end down.
 

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I only know what worked for me, but again I have ETS bars for improved bump control. I run everything full soft at all times except the front skid shock and don't change it for drag races. I change the ACM only. My skis lift less than a foot unless I scoot way back on the sled. It also 'calms down' within the 1st 100' or less but still feels light in the front. Id' think F and CK3 tunnels would respond in similar fashion running the same skids. Any setting you try that limits ski lift to a minimum and maximizes forward motion will be right. The best leavers in street races (or grudge race meets) usually throw a measurable amount of snow but they're long gone by the time the sled next to them is done crawling backwards over their tracks and dangling the skis. I never thought to mess with the limiters. I had them up one hole once but hated it in the trail. I didn't race anyone that weekend either.
 

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Highlander, with those dog bones you're coupled now and can get away with a softer setting on the pre load but regardless they are probably costing you a little right at the hit. Good for bumps though!

I usually try for a flat launch with a little bit of squat with the rear skid. Pull the pressure off the skis but no need to lift them higher then an inch or two, it just wastes HP and ultimately time.

Suck the limiter straps up enough to keep the front end down.
 

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one fast 98 mach-z
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Discussion Starter · #16 ·
see there is more than one way to set up a sled to win at drag racing . dam I was hoping for a easy answer . I will keep reading all replies.
 

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see there is more than one way to set up a sled to win at drag racing . dam I was hoping for a easy answer . I will keep reading all replies.
No easy answers but lots of variables. Find what works for you and have fun with it!
 

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Not a hijack, but thanks for the input mal. That's probably where I'm at, but I admit I've over compensated my steering control both with the ski choice and the limiter settings. If my sled is sitting still in more than 6" of snow the bars will break parts before the skis turn. The steering relaxes once I move even just a wee bit. Everyone who's taken a rip on my ol junk is happy to give it back due to the heavy steering, but when I want it to turn at speed it turns. I narrowly escaped serious injury or worse 3 times in 1 weekend with the old OEM skis and vowed to let her sit until I corrected the problem. I also admit I was one of the problems. I'm sure BRP never intended the 97 Z to be used like a 440 X-country sled. I just never knew it :p
 

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Carbide studs will dig a trench on ice if you hammer the throttle, learn to hole shot with just enough throttle to not break the track loose and you will win every time. Also how many studs you running?
 
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