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Sorry guys but I just have to ask. Having fitted a boost controller (apexi) to the Power FC, I see that it has 4 settings for different boost levels on the hand controller. Now here is the question? Does this mean that I need to tune the maps for each setting or does the PFC (wonderful piece of kit) automatically adjust/compensate for the different settings?

I'm not a mechanic or techo so please be gentle.

Cheers

Muz

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Muz,

You can set 4 different boost level's

eg:

1. 7psi

2. 10psi

3. 12psi

4 14psi

The ignition & fuel map will have to be tuned for setting 4, as its the highest boost setting so you don't get leaning out problem's etc. You can still run the other settings just it will feel sluggish because their will be the right amount of fuel for 14psi not 7psi etc... :(

:D

Jun

Muz,

You can still run the other settings just it will feel sluggish because their will be the right amount of fuel for 14psi not 7psi etc... :(

:D

Jun

Thats wrong.

It will run fine.

More boost measures more air flow through the air flow meter. So it will add fuel accordingly. If you are running less boost it will only add fuel for that amount of engine air flow.

The air flow meter doesn't care what boost it is, it just adds fuel according to the air the motor uses.

You would tune your engine maps right up to your maximum boost level. (maximum airflow)

And then anywhere in between manifold vacuum and maximum boost pressure it will add fuel according to the engine air flow at that point as measured from the air flow meter.

At lower boost there is less airflow obviously, so the AFM measures this and adds fuel for the smaller amount of air flow. If you run high boost it will measure more air flow and add more fuel.

Its really that simple, the principle anyway...

Does the PFC have tha capability to store 4 different maps for the 4 different boost levels, so that when you adjust the boost level, the correct map is automatically loaded? That would be ideal.

I guess the maps are not going to be significantly different up to a certian load on the engine anyway.

BTW: My knowledge of EFI tuning is limited at best.

Does the PFC have tha capability to store 4 different maps for the 4 different boost levels, so that when you adjust the boost level, the correct map is automatically loaded? That would be ideal.

I guess the maps are not going to be significantly different up to a certian load on the engine anyway.

BTW: My knowledge of EFI tuning is limited at best.

The PowerFC only has the capability to store 1 map.

I'm not to sure how the 4 boost levels are used. Maybe its time to read the manual. lol.

Thats wrong.  

It will run fine.

More boost measures more air flow through the air flow meter. So it will add fuel accordingly. If you are running less boost it will only add fuel for that amount of engine air flow.

The air flow meter doesn't care what boost it is, it just adds fuel according to the air the motor uses.

The o2 sensor controls the A/F ratio's and this only happens with closed loop enabled on the FC HC, with closed loop off it purly runs from the map load points.

If you were refering to closed loop mode then this is really pointless as the standard o2 sensor does not act very fast to high RPM, its known as Slow & Narrow and inless you have a wide band lambda sensor the A/F's wont be change very accuratly.

Eg:

Closed loop is used for mainly cruising tol lean the a/f ratio's out for better fuel ecomomy but this happen's after a few min's of cruising at the same speed.

:D

Nathan

Are you saying you have a comprehensive manual in english?

Not sure about comprehensive but I do have a English PDF Hand Controller manual in english.

Nathan, if closed loop kicks in after a few minutes of cruising its time for a new o2 sensor. Watch the o2 sensor on the h/c. It kicks in to closed loop mode no less than a fraction of a second once you start cruising.

There is no difference running your car on zero boost with the boost controller set on 10psi or 20psi, so there is no need for a different map. The power Fc is tuned at different load points and each load point represents air flow. You can trace the load points on the mapping on the Power Fc. Say, at 10psi, you are getting to load 10, then your car is tuned to load 10. If you raise your boost to say 15psi then you may reach load 12 on your power fc. Then loads 11 & 12 need to be tuned. If you get spike somwhere, you may reach load 13 at say 4500 rpm, but may drop down to load 12 at 5000rpm. Thats why you need to keep an eye on knock levels in case it hasnt been tuned there.

I am not sure I understand this thread at all, it doesn't make sense to me. Let me explain why....

The 4 boost settings on the PFC are exactly that 4 BOOST SETTINGS. If you want 1 bar then select 1 Bar, if you want 1.5 bar then select 1.5 bar. All this does is enable the ECU to tell the boost control solenoid when (how often) to close so as to limit the boost to that level. Nothing more, that's it.

You tune the maps for the maximum airflow you want to run. Whether you get there at 1 bar or 3 bar is irrelevant. The AFM measured the airflow and the ecu tells the injectors how much fuel to squirt according to the maps you have loaded.

Obviously a Power FC without a Boost Control Kit fitted still works fine, there is no boost table to set. On some cars the PFC doesn't even know the boost level (no map sensor). It simply doesn't need to, as long as it knows the airflow (via the afm) then it can do its job of matching fuel and air.

That's one of the advantages of an AFM sensor driven ecu.

Hope that clarifies:cheers:

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