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If the tuner has done his job properly that shouldn't be the case.  Boost is irrelevant, he is tuning to airflow as the primary load source, with rpm as the secondaary reference.  Turn the boost down and the airflow decreases at the same rpm, which should be reflected in the mapping (ie; the load points used).  If the tuner has mapped the load points correctly then no problems, power is maximised.

:( cheers :)

Exactly my point, if he's getting knock from a slight spike well......... :P

Already have, i am getting bad spiking from my boost controller causing massive amounts of knock.  The spiking did not show up on the dyno cause they start the acceleration before the turbo has spooled up giving the bleed valve more time to adjust to the pressure changes. 

The spiking is only happeneing when i put my foot down when the turbo is spooled up, so anywhere above 3000rpm.

I have dropped it back to 10 for now.  sure can notice the drop in power.  Knock is good now, cant make it go over 25, before i had a spike of 127 on the knock scale.  Very bad i think.

Spiking and knock due to mid range rpm WOT, suggests the tuner did not do his job.

Edited by Cubes
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Is this just the stock turbo simply running out of puff?

Yes..

And if the map in areas other than WOT was not tuned (as it seems by the spiking) then when u turn the boost down it wont be optimal, but yeah if the whole map is done then it will be ok.

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Yes..

And if the map in areas other than WOT was not tuned (as it seems by the spiking) then when u turn the boost down it wont be optimal, but yeah if the whole map is done then it will be ok.

What does WOT stand for?

How can i tell if the whole map is done? The ign map has been locked out so only zeros are shown. Is there any other way to tell if it has been adjusted from stock?

The AFR's are in: (cant post photo atm as girlfriend has borrowed the camera)

all in 4th gear

@80kph 12.5

100kph 12

120kph 12

140kph 11.7

160kph 11.9

180kph 11.6

Do these seem safe?

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If the tuner has done his job properly that shouldn't be the case.  Boost is irrelevant, he is tuning to airflow as the primary load source, with rpm as the secondaary reference.  Turn the boost down and the airflow decreases at the same rpm, which should be reflected in the mapping (ie; the load points used).  If the tuner has mapped the load points correctly then no problems, power is maximised.

;) cheers :)

so you're saying that if you turn the boost up or down, the maps or something will scale up or down accordingly, delivering different amount of fuel? Kinda like that factory ECU?

ie, Boost up, more fuel is used, boost down, less fuel is used etc. ??

I'm a little confused.

I just thought the maps would inject the same amount of fuel, regardless of the boost..

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yeah its as gary has said, if you turn boost down the airflow wont measre as much air therefore the load maps when you floor it etc dont read as low on the load map. the left side of a map is load and top is revs. load is based on the airflow meter value. half way down the left side is about 3000mv on the airflow meter. load point 15/16 is 5100mv on the ecr33 powerfc.

the tune should scale around the environment, as its supposed to

more boost, airflow levels change, less boost it changes again

much like the water temp and air temp correction modes

the hotter the intake air temp the powerfc backs off a % of timing cos the air intake is too hot. if the water temp is too cold it does a % correction on the timing and fuel to make it heat the water up and also to not make the engine run hard when its cold

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WOT stand for Wide Open Throttle, and sometimes a tuner will just tune the part of the map that is used for WOT and leave the rest, which is used for driving other than when u are flooring it.. So this can make it safe and fast at WOT but when driving around normally it wont be optimal.

The afrs seem normal, but i cant really comment because each tuner seems to have different opinions when it comes to AFRs.

Edited by siksII
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Stock Fuel pump and injectors?? Dont the stock items max out at 180kw-190kw??? Is the car running good with these items. I'll probs go the same path and keep these stock but want to know if these are supplying your beasty engine enough juice.

I am lead to believe the injectors are still good a little bit over 200rwkw but fuel pump upgrade will be needed if i want any more power, (just to be safe) with maybe a high pressure reg just to squeeze a little bit more out of the injectors.

My current setup runs fine, see AFRs above post

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I had a play tonight.

10psi, uses load point 15 on the map.

12psi... Still uses load point 15 on the map. :)

13psi.. Load point 16.

12 & 13 psi was able to take 18degree's where as 10psi was able to take 20.

That definitely tells me that for minimal boost changes you must have the car tuned to suit, you as I, may find you can dial in some more ign. timing at the lower boost level.

If the tuner has done their job correctly, it still won't be optimal.

UNLESS you are lucky the lower boost level you have chosen uses a different load point and has been tuned accordingly, OR your running an autotronic/motec with a 40x40 map, allowing a much higher/finer resolution.

The PFC's tend to have a nice fine resolution up until wot when running some decent boost, then they tend to become a little coarse.

I'm unsure if the PFC calcs the cells around it to derive a part cell value.

i.e

Load point 19 runs 20degree's

Load point 20 runs 18degree's.

You really use half of load point 19's airflow so it does a calc and throws in 19degree's. :wub: If that makes sense.

Edited by Cubes
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I had a play tonight.

10psi, uses load point 15 on the map.

12psi... Still uses load point 15 on the map. :rolleyes:

13psi.. Load point 16.

12 & 13 psi  was able to take 18degree's where as 10psi was able to take 20.

That definitely tells me that for minimal boost changes you must have the car tuned to suit, you as I, may find you can dial in some more ign. timing at the lower boost level.

If the tuner has done their job correctly, it still won't be optimal.

UNLESS you are lucky the lower boost level you have chosen uses a different load point and has been tuned accordingly, OR your running an autotronic/motec with a 40x40 map, allowing a much higher/finer resolution.

The PFC's tend to have a nice fine resolution up until wot when running some decent boost, then they tend to become a little coarse.

I'm unsure if the PFC calcs the cells around it to derive a part cell value.

i.e

Load point 19 runs 20degree's

Load point 20 runs 18degree's.

You really use half of load point 19's airflow so it does a calc and throws in 19degree's. :P If that makes sense.

Tell me if i am understanding this correctly.

If i have dropped the boost from 13 to 10 psi and a lower load point was choosen then that lower load point should have a higher ign timing value therefore making the most of the tune? But if a lower load point is not choosen then you should be able to dial in a bit more ign timing?

Now how do i check and adjust all this if my maps have been locked? I know its probably not recommended to play with it but i guess its the best way to understand how the whole thing works.

Even though i have dropped back the boost I am still getting a knock spike, its just at a safer level now. But the spike is occuring at the same rpm every time no matter what the boost setting is. Which leads me to think that there is a slight problem with the map. No discredit to the tuners as I know for sure that when it was on the dyno, knock never went over 30. Its just behaving differently on the road. What should be monitored and adjusted to decrease the knock at that rpm?

Here are some picks of the knock vs rpm on the chart,

The 1st pic is of the lower boost setting the other 2 are the higher boost setting

post-3430-1130023741.jpg

post-3430-1130023780.jpg

post-3430-1130023827.jpg

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Is it knocking just as boost hits?

I find with mine when boost initially hits it drops to say load point 16 for one rpm cell then levels out to load point 15 once accelerating through the rpm.

If the values in load point 16 are either too lean or too much ign timing it will tend to get a bit of knock, this is only seen in mine when I drop it back to third at a higher rpm and punch it.

Bring it up through the rpm smoothly as it does on the dyno and it is fine.

Do a map trace, press the next button and it will highlight all map points used. Then you go in to the ign map and check out what the values are. If he's locked the map then I would be pissed as, I had to make a few little on road changes to my tune as it was doing as I said above.

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Does anyone know how to unlock the map yourself or does it have to be done by a laptop which the tuners have.

I just got back from a drive and noticed that with the a/c on it makes the knock spike even worse. dont even need to be 1/4 throttle. Very strange that its happening at the same rpm every time.

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