AVC-R do You use F/B Speed?
 

Hi All,

I would like to know if You uses the F/B speed settings in the AVC-R or scould i just turn it off?.


One other thing, today when i was driving the car and i was ging wot the boost overshoot to 1,5bar when i have it set at 1,3bar but it only did it one time,the next time it was at 1,3bar,so i was thinking when i have driven it hard to get the boost stable ,can i then turn the selflearnng of.

It says in the manuel ,that if the gear startduty is at 0% the selflearning will be active,does that mean that if i give it some startduty in the lower gear it will not go to selflearning at all????

Thanks for all info
Skassa

F/B speed = i use it...didn't notice any difference though

Overshoot = it all depends...i had 0-3k rpm duty set to 90% as i was told there is no way to overboost TD05 before 3k...well, i used to get 1,7b before 1,3b at 3,5k rpm...depends on gear and at what rpm you are...

Self-learn = it wont learn in gears with altered startduty (usually 1/2/3 gear)

I also sometime have problems (hesitation/backfire) in 4th at 6-7k rpm and sometime i don't...go figure...

CeeDee, You could get 1.7 bar from a TD05 at 3000 rpm ? Was this on a 2.5 ?

2 Andy: Nope...plain vanilla 2.0l EU GT my98 (phase1 engine)...I think you suggested to me in othere avc-r topic to use 90% up to 3k rpm...well this is the result 1,71b to be precise in 2nd gear...my duty was 90% up to 3k rpm and 48% at 3,5k rpm at a time...now i lowered it to 65% at 3k rpm and still getting around 1,3b...maybe Dawes and AVC-R combo should be a good thing after all for faster spin without high boost in low rpms...

1.71 bar at 3000 rpm !!! That is an amazingly low boost threshold for a td05 in 2nd gear :eek: You sure its not an 04 ;)

Andy

Andy : i'm sure it's not td04...it was 04 before i changed it for 05 month ago...

LOL at Andy. ;)
F/B set at 33333.
Learn gear off for 1st and 2nd. (+35 +17)
Learn gear might be a good idea in 1st and 2nd on a smaller less "violent" turbo.
Following Andy's input it is behaving itself again but we did find that for some reason there was a problem controlling boost on "Settings A" but with the same settings in "B" it was O.K. Very strange.
Anybody got any ideas?

Hmm,
Thanks for the speed setting,that´s what it is default.'

Maybe i schould try the "B" setting as mine will overboost shortly if have not been in hi boost for a day or two...

Thanks
Skassa

2 harvey : u actually have +35 and + 17 for 1st and 2nd gear ???...is't that too much ? (i have +6 and +4, and +1 for 3rd)...since i wanted to experiment a bit with andys suggestion of setting 90% up to 3k rpm i had to turn off 3rd gear learn off couse in town driving i accelerate often from 2k rpm in 3rd (and avc-r than mess up with 90% duty)...FB is 5/4/3/3/3...i'm also on A setting (never thought it was important)...One more thing i noticed...i changed my BOV for TurboSmart one (piston type)...it's on 2/3rd on a hard side and i noticed i'm getting steadyer and faster boost than with standard BOV...

I really dont have any whish to BS you about boost i'm getting with 90% duty (it's nothing to be proud of) and all i want is to learn and manage to set it up properly...
It is slower than td04 but that was a boost i was getting with 90% duty (before i lowered it)

Have you removed the supply restrictor ?

What exactly is a supply restrictor ?

There may be a restrictor in the pipe coming off the turbo snail. Remove it. They are usually in the first couple of inches of the pipe.
Then start again!!!

On mine i have only +5% in first and + 4in second and -2 in 6th

But last night it was boosting to 1,7bar in second(that´s wild):D

Skassa

2 harvey: i do have that restrictor in place...why should i remove that ?

2 denmark : so i'm not alone in 1,7b club :)...only thing is that i would like to understand why/how it overboosts to 1,7b and how to limit that behaviour...it may feel great but i would like to be the one in control...whats the point of having controller if it doesnt control things...
Maybe F/B is to low for 2nd gear...who knows...

Yes but my 1,7bar is around 6000rpm....

Skassa

The restrictor is only necessary for the factory boost control system.

If you do not remove it then you can (and you do !) get boost spikes.

The reason for this is that the AVC-R is trying to give you the best spool up possible. To do this, it holds the boost solenoid at 90% duty, ie venting 90% of the signal for as long as possible, prior to allowing the correct signal to the wastegate actuator.
If you have a restrictor in the line then the signal will have a delay in building up pressure, this is not what you want as it will cause a boost spike.
If you remove the restrictor, then the boost control becomes 'sharper' and ultimately controls much better. As a result of this you will need to reset your duty cycle profile
in order to achieve your boost targets.

Andy

Thnx Andy....i will do that and inform you about results...btw. any recomendations for spark plugs which to use for 1,2b boost...7 or 8 (regarding that slight hesitation in 4th at full boost at 5500+ rpm...i hope new plugs will help)

7's should be fine, I used 7's for around 430 bhp, I only fitted 8's when I was doing some sustained top speed running and stretching the poor little turbo to over 440 bhp.

Check your plug gaps, consider reducing them slightly. What AFR is the engine running as it approaches the misfire at 5500 rpm ?

Andy

I use 8's at a moment but will switch for 7's...as for AFR...well i'm not sure about that, better to say i'm confused...I do have HKS AFR thingie installed and i put that to 9th position...but...if HKS AFR is at bypass setting i'm getting 0,87mv...if it is on 9th place i'm geting 0,876...i'm aware that is to low but judgeing by exhaust smell and color i'm having more than enough fuel...this mv numbers i got from small mv meter i connected to ecu which gets it's power supply from 9V battery (couse it needs steady power for accurate measure)...maybe battery is going dead and it underreads...i think i have more than enough fuel but cant be sure...i will connect select monitor soon to see what it reads...any suggestion wellcomed as usual

Thats dangerous imho...i think your wastegate can't flow enough and you are getting boost creep (sounds like it, that is)

It just did it one time,the wastegate is ported and if only i keep it over 1,3bar there is no trooble with boost creep.When i turn off the AVC-r it goes 0,6bar all the way to 6,5k rpm and the raises to 1,3bar...

It´s not a problem as i drive it over that..

Skassa

2 Andy : Update...i did what you suggested, removed restrictor in pipe from turbo ti NO port on solenoid...than i started with boost duty of 55% and avc-r picked it up and switched to learn mode...well, everything is ok (boost is steady without spikes in 1/2/4/5) gears EXCEPT im getting huge overboost in 3rd gear...learn mode is on only for 4/5th gear...start duty for 3rd is 0...i get no idea what is cousing that overboost (1,6b while in all other gears it's 1,15b) and how to solve it...any advice?

thanks upfront

No idea why 3rd gear should react in that way ? Is 3rd set up correctly in the speed set up menu ?
Have you tried the same settings in map 'B' ? AVC-R's have been known to act up on one channel and yet can be perfect on the other channel.

Andy