'11 Pro Twisted Turbo bog-stumble

[teamwelfare]

been running my pro with twisted set up. have some stumbling -bog when trying to ride at slower speeds off boost ( tree riding ) and when coming out of pull and heading downhill as well as when heading down the mountian. seems to be worse between transition off boost to coming onto boost. also end of last season had issue when throttle held wide open would cut out unless let off just a bit. running a garrett 2871 with attitude ver 3.2 controller, air to water intercooler, etc.. usually run 100ll mix with 94 oct pump- 50/50. been keeping it around 6-8 lbs boost, would like to run around 10!anybody out the have any base numbers for the attitude box also any ideas what the fuel pressure should display on gauge? I would like to get this kit working better!

 

[sledhead306]

not sure exactly on how the twisted setup works, but i know the stock polaris fuel pressure is in around 62 lbs, do they have a reg to cut the fuel pressure to lean it?, then use the fuel controller to put it back in?

 

[E-Zmoke]

I'm sorry to inform you but you will never be able to fix the problems you are experiencing on that setup. We dealt with the same issues for two years in constant talk with Shain, went through a crank because of the oil injection delete. Then went through 2 top ends before upgrading the fuel system to a Boost It fuel system. Last year the sled ran top notch all problems gone after upgrading. 6lbs boost was equivalent to 10lbs on the twisted setup and all bogs and cutouts were gone. You may be able to clean it up a bit if you upgrade to the Dobeck 3.5 but you might as well just do it right if your going to spend the money to fix it. I would highly recommend you putting the oil injection back on your sled ASAP if you haven't already? Here is a link to the fix to your problem. Any questions, give Neil or TJ a call and they will explain how their system works. Hope you have a great season!

 

[teamwelfare]

Will definetely try to get info on the boost-it system, yes my sled has always had the stock oil injection utilized.

 

[E-Zmoke]

Will definetely try to get info on the boost-it system, yes my sled has always had the stock oil injection utilized.

Utilized as in being used to lubricate your turbo or being used as normal to lubricate your engine? In the first year of the twisted kit, they used the stock oil injection system to lubricate the turbo and eliminated it from the engine, and told everyone to mix oil with their fuel. This is a huge issue as the crank on the pro is a "dry" case which means limited fuel/oil actually gets down into the case. They realized their mistake and changed their oiling around after the first year. You need the stock oil system connected to the crank to properly lubricate the crank on this engine.

 

[teamwelfare]

Seems to be the way the fuel pressure works,

 

[teamwelfare]

Oops yeah sorry the stock oil injection system is still intact to lubricate the engine and has a seperate oil reservior with electric pump for turbo lube.

 

[moto5151]

I run attitudes complete turbo setup on my 12 pro. I have no issues with tuning, or any sort of stumble. Although our kits are different, the fuel system is the same, I think. I run 40-41psi of fuel pressure, with 10lbs of boost. Its very finicky to fuel pressure. Anything below or above seems to give the stumble your talking about. But once it's set, I never have to touch it. Initially, when I got the controller, I couldn't set it. A after I spoke to attitude, they informed me that the color led, on the controller are different then all the other dobec style boxes. Only for the pro.... Tunes more like you would a carb. Green is idle, yellow is mid, reds woti, then the color combo's correspond with the single color. Its the set points, where the next color takes over. I suggest calling Derrick at attitude directly.
I can't remember exactly where my numbers are set, green is at like 2, yellow at 2, red and 4, etc... Start by setting your fuel pressure, then green, make it idle rich=higher number, then work your way down until it's lean. Watch your afr gauge. Mine idles at 14.5, then as I move it usually goes up to 16. Once I'm at like 3500-4500rpm it goes down to 13.0 and stays there until wot.
I've never touched my oil delivery system, have a separate oil pump for turbo oiling.
In fact, I didn't even mix oil in my tank for the first 1500 miles. I do now, just for injector lube.
Good luck.

 

[E-Zmoke]

Wow is that ever confusing! The Boost It box is up or down on main fuel and it spreads it across the whole map in one simple setting. Then you can go in and fine tune every 250rpm interval if you want. I couldn't even imagine trying to fight with a bunch of flashing lights again. Just saying...

 

[Clode]

the boost-it box is so simple, in under 5 mins you can be dialed in and it will run consistant day after day....they are well worth the money

 

[teamwelfare]

Sweet k will definetely check my fuel pressure again and bring up to 40-41 psi if required then retune! Sounds like will help my issue!

 

[moto5151]

Yes i totally agree, the boost-it setups absolutely the way to go, and guaranteed next year I will own a 15 pro with boost-it turbo. But, this thread is asking for help, and we deal with what we have. Make it the best we can. Theres no reason why he can't tune this setup to work great. Yeah its a little more work, and all those flashing lights might confuse??. But none the less, with a little work it can work good.

 

[teamwelfare]

just wondering about the fuel pressure adjustment. I have a bosch 280160001 rising rate fuel pressure regulator looks. there is also a hose coming off end of adjustment screw going into intercooler to sense boost? i turned in regulator and am getting 38 psi at idle. with this boost line going into regulator should this bring pressure up when boost air applied to regulator? also noticed regulator on return line and routing of fuel lines filter to stock rail, stock return line runs to extra rail for supply then out to regulator back to tank. seems ok , just wondering why stock fuel pressure higher (60 psi range ) and with turbo kit /extra injectors etc dropped down to lower pressure with regulator?

 

[moto5151]

Sounds like you have the fuel lines routed right. The fuel regulator I use only has 3 hoses. One in, one out to tank, and one to my gauge. I use a 1:1 regulator. With my kit, I removed the regulator in the tank, on the pump. And installed a blank plate.
Do not quote me on this, but I think the fuel pressure works like this. In stock for, the fuel pressure is zero until it's started, then 60psi fuel pressure is maintained, the excess is put to tank unobstructed.
With the turbo setup, the fuel pump still provides 60 psi, but the in line regulator is used to hold back 40psi at all times. When I shut my eng off, my pressure stays at 40 for a long time. Fuel pressure does increase with boost. Although I've never really paid attention to what it goes to, I'm usually too busy watching afr. If fuel pressure dropped off you would see a lean value.

 

[teamwelfare]

k thanks that does make sense...seems I may have a regulator issue. when I got the sled I noticed the fuel pressure stayed up a long time after sled shut off, now it does not do that drops off quickly also I lost 2-4 psi fuel pressure at idle. As stated I tried turning in adjustor on regulator but can only get 38 psi @ idle. I am thinking I should be at 40-41 psi @ idle. yeah I cannot look at guage when riding as trying to watch afr when can. Some of my stumbling and afr issues started when fuel pressure stopped holding and lower idle psi. When at WOT afr would spike to 17 - guage would go off scale and let off throttle just abit and was ok..even with controller turned up. I may be thinking the 1:1 regulator may be a better choice for this kit. Seems like most of issues may be do to thirst for fuel! By chance have any info on the regulator you are using?