MCXpress Boost adjust
- Thread starter Snoboner
- Start date
E
Extreme-One
Well-known member
Pretty sure you shorten the rode for more boost and lengthen the rode for less...
Not sure if this applies here but if a guy want to run the upgrade and has the external pump does one just have to adjust the wasteagate? Set it so the low setting is 15 and the tpc thing will adjust to 17 lbs? Is there something else that has to be done? Fuel regulator? mapping?
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woodies
Guest
on my sled i adjusted the linkage one turn out to lower the boost. if you go any more the waste gate starts to open and you lose spool up. you need to ensure the gate is fully closed when hooked up. your boost adjuster should be able to turn the boost up, why would you got to the linkage? different style?
I think you have to have your controll box reprogramed. that may depend on kit. I would call mark at liepenheimer yamaha in butte montana. he could answer your ?s oh and there is nothing in the instructions about adjusting the control rod.
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woodies
Guest
call walt healy motors in calgary, i just put the external fuel pump on mine to feed it more fuel. the regulator is self adjusting and you set your starting pressure. i put a gauge in line and left it so i can check in about 1 minute the pressure. i should get pic and post if you decide to go that way.
How do you adjust the starting pressure? Again the early kits came with an external fuel pump. What is needed to be done to run stage 2 -17lbs?
If you have one of the early kits a reprogramming of the ECU is a must for sure!
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Washy
Active member
You will have to shorten the wastegate actuator rod to increase your base boost. Or you can go to a hallman and turn it up and down at will. I have my base boost set at 10 psi and crank on the hallman to increase boost. MCX(erik) told me to run 15.6 psi at sealevel on pump gas, I would try but, dont really want to be the one to find out the hard way.
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woodies
Guest
there is adjustment screw you unlock then turn to increase to 44lbs, i turned mine up to 48 at idle. still need more fuel but thats a different story!
If you have an early Nytro kit with external fuelpump, you don't have the fuel regulator, sorry.
And if you add an fuelregulator i know you need 2 reprogram the ECU.
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Washy
Active member
My kit is a early kit and it has the regulator????? If there is no regulator what is stoping the pump from continuously running until it pressures up high enough to stall it out???? They are not a on/off pump. If it has an external pump it has to have some sort of regulator.
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Of course it has an regulator, sorry if i was unclear, all sleds with injection have an regulator, but MCX change the stock regulator to an adjustable 1:1 regulator that rises the fuel preassure as the boost rises!
If i'm not misstaken stock fuelpreassure is enough to ~240-250hp, but not 270hp, thats why it's important to change the regulator, much cheaper then change the injectors.
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Washy
Active member
Yes but the early kit comes with the 1 : 1 rising rate regulator with the external fuel pump and mapped to 18.5 psi. On my kit the stock regulator internals were taking form the stock pump assembly and put into a new housing (supplied in the kit) that makes it a rising rate regulator.
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Hmmm, i wonder how this discussion went from "If there is no regulator what is stoping the pump from continuously running until it pressures up high enough to stall it out????" to you in next breath write "On my kit the stock regulator internals were taking form the stock pump assembly and put into a new housing (supplied in the kit) that makes it a rising rate regulator" 
Anyhow, theres a couple of variations out there, hard to tell what setup (map, regulator) diffrent kit have, but i know the 270hp kit hitting the snow spring 2008 was developed during winter/early spring 2008, the early kit released autumn 2007 differ from later kit, tuning vise.
Anyhow, theres a couple of variations out there, hard to tell what setup (map, regulator) diffrent kit have, but i know the 270hp kit hitting the snow spring 2008 was developed during winter/early spring 2008, the early kit released autumn 2007 differ from later kit, tuning vise.
