850 turbo lag, clutching?

[chickenstixx]

2019 850 boondocker intercooled sidekick.

First two stroke turbo sled.. power is awesome runs rpm right where it's supposed to on the top end. Builds boost back real fast when fluttering throttle once it has been boosted up.

Right now the clutch engagement is about 3200 and really nice and soft which is what I like.

Only thing it is seems sluggish building boost but I really don't know since I've never ran a turbo smoker before. Is a lazy-ish bottom end expected? To be fair to the sled it shoots snow out from idle, just not as hard I guess as my last 850 n/a.
Should I add more spring to the secondary to make it shift slower?

I do like the soft starting/ low rpm primary clutching. Have been running it for a few years now vs trenching *hard hitting* or whatever 4200 rpm engagement setups

Thanks.

 

[A@ron]

Rpm spins the charger. Higher engagement may help with building boost quicker. I’m right around 4300 rpm

 

[Chadly]

I hate to break it to you but they never got the 850 intercooled turbo to run right. I bet you got a really good deal on that sled... They all had lazy bottom ends and bog if you chop the throttle.

 

[chickenstixx]

Rpm spins the charger. Higher engagement may help with building boost quicker. I’m right around 4300 rpm

Do you get much trenching? Out snow is usually reaaaaallly light powdery snow.

What primary brand/color is it

 

[A@ron]

Trenching is more related to track choice, suspension set up and throttle, I’m on a 155 2.6 and my sled hops right on top of the snow. There are certain instances where you have to feather it. It’s all situational for example grade and snow pack. I believe on putting that turbo power to the snow asap because when you need it you want to be able to have it.

I’m running trs clutching with a gates belt.

 

[A@ron]

Forgot to mention I ride Colorado dry/sugar 100 percent of the time

 

[A@ron]

I hate to break it to you but they never got the 850 intercooled turbo to run right. I bet you got a really good deal on that sled... They all had lazy bottom ends and bog if you chop the throttle.

I believe his engagement is too low which would keep the turbo from staying closer to spooled

 

[chickenstixx]

I hate to break it to you but they never got the 850 intercooled turbo to run right. I bet you got a really good deal on that sled... They all had lazy bottom ends and bog if you chop the throttle.

lol mr. doomin n gloomin.

it doesnt have any bog anywhere.
geting 16-20 inches this weekend, going up the mountain again!

 

[Wheel House Motorsports]

Thats crazy low engagement. I'd almost bet the primary spring is broken.

Hard/soft engagement more has to do with proper belt to sheave clearance & belt deflection. The RPM it happens at just makes the bad sloppy tolerances less noticeable. The "bang" into gear is less noticeable at 3200 vs 4k+. Also, what is the condition of the belt? the 216 belt on the 850s is hard as a rock and will wear deecently and never pull threads or blow, that being said, they will often wear a LOT thinner reducing bottom end performance drastically even though they "look" good at a glance. Quick way to see is by examining the top edge of the belt. on a new belt there is maybe .080" of flat vertical wall. By the time that vert is no longer visable or almost gone the belt is worn too thin greatly increasing belt to sheave and reducing botom end performance and spool. It should be relinquished to a backup.

What is the current clutching in the sled? What is your belt to sheave clearance?


As much as chadly's response is a ittle doom and gloom, those sleds definately are not the best out of the hole of really any recent generation 850's. that being said, they can be made to work fairly good.

 

[chickenstixx]

its a dalton 100/305 or whatever. i ordered some new bets, spring, belt clearance stuff from TRS last night.

its not "bad" at all. it runs fine and shifts smooth. my intercooler pump was also busted so it should run better this weekend.

I'm thinking of welding in a reed valve slot into it to pull air during low rpm-vacuum acceration like the new kits and factory polaris turbo does sometime this season too.

 

[Wheel House Motorsports]

Awesome, sounds like your on the right track.

Its a lot of stupid tiny little things that will add up to getting that last little bit of super clean performance.

 

[diamonddave]

I’m sure glad we have our resident forum experts donating their highly valued time and technical expertise to those of us who aren’t in the know.

 

[A@ron]

I’m sure glad we have our resident forum experts donating their highly valued time and technical expertise to those of us who aren’t in the know.

Care to elaborate on that?

 

[madmax]

I’m in agreement with others on your low engagement contributing a little bit. I usually had my turbos engage around 4000 rpm because like the others have mentioned keeps low end turbo speed up a small amount that may help. Once you get your clutch alignment and belt deflection set with your new TRS clutch parts report back. Make sure your belt deflection, clutch assignment and belt to sheave clearance are all set correctly with a new belt for optimal performance