AFR with MCX 180 - 190+ ?

[kimoajaj]

Hi guys!

I got my Grimmspeed boost controller and it looks sweet!

Next episode:
CROSSROADS

hehe, Erik Marklund tells me to adjust the MCX to get the boost levels correct and that he doesnt see any benefits of installing a manual controller.

Have anyone tried re-programming the MCX box to make it work better? (adjust the altitude compensation)

Erik also said that the TCV/MCX could adjust the boost pressure according to RPM , for example it could reduce the boost close to the rev limiter. However he didnt say wether the boost is programmed according to RPM in an untouched stock MCX box).

I went riding together with Dimebag last weekend in Sweden, we started off at about 500m I think, at the highest we were at 1500m, as we climbed up to the highest point I did have a good amount of throttle.
I just checked my boost gauge (it has memory peak recall) and I had never been above 4 PSI throughout the whole ride.
Basically this means I am close to running 4 PSI to little at 1500m.

If this is correct I am running much less then 180hp!

I guess I should do as Dimebag sais, install the manual controller, adjust the base pressure to 4 PSI at sealevel on a cold day, that way if the temperature increase much one day I will still be safe.
If I have understood, the base-pressure will be the pressure my sled will be running if the manual controller is in the zero boost position - spring inside the controller is at its most slack position)

This way I will always know that if I turn the knob all the way out to zero boost position I will be running 4 PSI.

Basically this means that if I install the manual controller and let the knob on the adjuster at zero boost, my sled will be running exactly like it did with the TCV. (theoretically since the TCV dont do its job).
Or am I stupid?

Basically I don`t know what I am waiting for? Agree?

 

[kimoajaj]

Just so you know, at one time last year I saw 6,5 psi, where I have my warning light set. This was at about 500m.

Is the TCV unstabile?

 

[Dimebag]

I wouldn't call it unstable. Useless is the word you are looking for.

 

[TBird]

I disagree, never had a problem with mine.
Ripped off the manual controler i had on my Nypex and installed an TCV instead!

 

[rxrider]

1500 meters is not much, if you go riding above 2500 meters I would assume the TCV will do its job.
The boost map adjusts rpms vs throttle position.
It's fully adjustable.

 

[Dimebag]

Yep, thats exactly what Im thinking.

TBird, what elevation do you ride in?

 

[kimoajaj]

Got another mail from Erik today.
He still seems negative to the manual boost controller and sais that I should reprogram the TCV altitude compensation.
Dimebag: I recall you saying something about that the TCV actually isnt able to function properly at our altitudes / it isnt able to sense smaller altitude changes like 500m. Setting it to be more sensitive wount help if it actually can`t feel the difference?

To test if the TCV works Erik said that you could pressurize it with 10-50kpa (1,5 - 7,5 psi), turn on the ignition and then hear/listen if the TCV makes a click (before the fuel pump stops running).

I think the TCV can be OK but still not doing its job properly.

I guess I will have to install the Grimmspeed.. it does look awesome!

 

[kimoajaj]

Hey, does anyone know if there is a boost gauge that shows total KPA pressure?

Atmospheric pressure + boost pressure = total pressure.

 

[Dimebag]

Get that mbc installed and come ride with us. You won't regret it.
Ps! we got fresh powder

 

[TBird]

TBird, what elevation do you ride in?

I ride mostly ~400-800m, occasionally @ sealevel and up to ~1200m as highest.
That it keep total preassure @ same level is without a doubt, for me anyway.
TCV valve also let me modulate boost @ diffrent rpm which i appreciate a lot, it's great to keep boost under Control so i only get max boost @ full throttle, in the trees it's much nicer to ride when max boost isn't reached @ once.
But different strokes for different folks.

 

[Dimebag]

Its strange that we never see any increase in boost with the tcv, and you do..

Could it be different type valves? Or that you run a higher base pressure, and that the valve works better for higher boost levels?

Just speculating..

 

[TBird]

If i would speculate i would guess freezing as an issue!
Depending on when the problem occur, if it doesn't work as it should when it's -20°C and during powder boondocking, or if it doesn't matter if it's sunny and +5°C.
Also, i don't bring the sled in and out of my garage often so there's not much condense build up that could make any hoses freeze.

I removed the manual boost controller because i don't want to have to remember to change the boost manually, and i wan't to be able to adjust boost depending on rpm.
But if i had had bad experience with it i would see it diffrently, but i have run MCX since 2007 and never had a problem!

 

[rxrider]

MCX Display Unit displays KPa

 

[kimoajaj]

Do you know how much is an MCX Display is Rxrider?

Now there is no way back, I installed the manual boostcontroller today
(well hehe, I didn't remove the TCV I just disconnected it and plugged it with a hose so that I can go back to it without much effort)

Here`s how it turned out:

Maybe a little too far out, could have placed it somewhat longer in but we`ll see.

Can`t wait to try this!
Maybe there will be some testing this weekend, some people say it is possible to make it up to somewhat higher elevation on the island where I come from, but there is very little snow at sea level. Will keep you posted

OH btw sorry for the dirty sled, trailered it without the cover:/

 

[rxrider]

SEK kr 6000,-