Rb26 Gt-ss Turbos - When Should Boost Kick In?

[R31Nismoid]

AVC-R could be the issue

Its not the best tool for the job.

You need a good dual solenoid setup

[Roy]

What does the warranty cover though. Could be its only makign the power it is because of a problem they are masking???? So takign it to someone else may help identify the problem.

And its a big problem when a std RB20 with a Trust setup is making similar power, better response with an extra 4psi !!!

...and if you dont want the AVC-R, i will buy it. I like them and am lookign for another (Seriously)

[Bass Junky]

Are you near your car?

Get us the settings on the AVCR

[justinfox]

You know how it is guys, loyalty, egos, client and mechanic relationships.

It's all in the mix here and treading carefully is high on the list of priorities for me as I don't want to upset anyone, but yes I also want my GT-R to be right so it's looking like I gotta do what I gotta do.

Thanks heaps for all the suggestions once again. Much much appreciated.

[Roy]

Unless the AVCR is faulty it wont be the cause. You cant set them so wrong they hurt the response of the turbos so badly. Boost spikes yeh, but not hurt the power so badly that even at 1.2bar its only makign 270odd and the response is up the sh1t

[Swiper the Fox]

the gain setting on the avc-r looks to be affecting output (hence the wavy line on your power curve) Jim (Croydon) knows this boost controller inside-out and can set it up properly (although he does not recommend them). Blitz controllers are quicker to ramp up boost and keep it steady better too, we made the same power with 4psi less boost just by changing the avc-r for a blitz controller.

Disclaimer: the information given in this post may be total bullsh1t.

[R32gts-t]

I know you guys wouldnt usually go onto the silvia forum, but this thread is worth a look, it's not always a majorly technical problem, i'm not saying that the avcr isn't faulty or needs to have the duty retuned i'm just saying it's far easier to eliminate the simple things first.

After all the concept is the same,

The car in question was a 180sx, it had upgraded turbo with the additional bolt on's that come with it, it had similar problems to what you are having with your gtr, the guy spent a lot of money replacing things having things retuned etc etc, when in the end it was just......

read this:

http://www.nissansilvia.com/forums/index.p...=132004&hl=

Edited November 9, 2006 by R32gts-t

[steve_gts4]

my gtr with r34 n1's with all other mods similar is behaving like this too... hmmm time to do some investigating

[Faid]

I have driven a 33 with the GTSS, it was built and tuned in japan, tha car was resposive as hell, when boost kicked in and the car hit his midrange it would light the tires. the full boost hit about 3400. as for your AF ratio, it looks quite good from here, you sould get a better boost controler, i run the blitz with a tripple solenoid setup, have a friend that runs a AVCR in his evo 4 but that thing spikes like crazy (if you are foolish enough to run 24psi through that controler)

[Busky2k]

AVC-R could be the issue

Its not the best tool for the job.

You need a good dual solenoid setup

Not necessarily. The AVCR does a good job when its setup right. Its a pain to perfect but just because a EBC is dual solenoid means nothing! I've had a few mates whose Blitz ID-III/iColor is causing them havoc too.

I vote to see your AVCR settings which include the map, gear judge, learn gear and feedback values. By the wavy powercurve, your target boost setting and the duty cycle mapping is probably too far off and your feedback values are too high.

Edited November 9, 2006 by Busky2k

[Bass Junky]

[raz0r$harP.UK]

Justin have you gone back to Indy to ask him what he thinks?

[RellikZephyr]

sorry to go off topic a little

but where should the GT-SS boost in the rev range?

Justin talking about 4500 obviously too high but where should it be? 3500? 3000?

RellikZephyr

[SLVR32GTR]

Yeah there is something definitely wrong there, my GT-SS's come on strong from 3000rpm in the higher gears and around 3500rpm in first from memory. They feel a bit laggy between long gear changes, but if your quick it is full power the whole time!

I just love them for that reason, you put your foot down and your away. Response wise, i was next to a new wrx sti the other day, and off a slow rolling start, i came on boost only a fraction of a second after he did.

[RellikZephyr]

very nice

i love turbo cars but could never have a large turbo cause i hate turbo lag

RellikZephyr

[RS500]

have you checked that your actuators are set correctly?

you could be getting boost creep which is making it feel sluggish down low due to the wastegate flapper opening too early.

[RellikZephyr]

can boost creep occur with std turbos and actuators?

can it be felt as lag on gear changes?

cause i have std turbos and it feels little sluggish and doesnt get full boost (1 Bar) till 4k is that normal?

what causes and cures it?? had this for a while but wasnt that worried about it (and no idea what it was)

note: boost controlled by EBC

Sorry to hijack this post

RellikZephyr

[R31Nismoid]

Not necessarily. The AVCR does a good job when its setup right. Its a pain to perfect but just because a EBC is dual solenoid means nothing! I've had a few mates whose Blitz ID-III/iColor is causing them havoc too.

I vote to see your AVCR settings which include the map, gear judge, learn gear and feedback values. By the wavy powercurve, your target boost setting and the duty cycle mapping is probably too far off and your feedback values are too high.

The AVC-R just doesnt keep it going well enough is what it seems, regardless of "how well" you set it up, its simply not the best tool for your money.

On a mild turbo, with ~15psi, no worries. AVC-R isnt too shabby, but if you asking a lot of the setup, you'll be disappointed time and time again.

If people want to spend lots of $$$ trying to get it close to acecptable, thats thier choice. Im just pointing out that there is an easier way to do it.

ferni had to change controller aswell because he was having issues... cant remember what he did have but i suspect it was the avc-r.

It just didnt do the job well enough. It worked, yeah, but there is better stuff out there for the same/cheaper price.

[Roy]

But Ash, i cantr be the only guy that was running an 8psi spring pressure and with a bit of adjustment and self learning on the track it held 18psi no problem. Thats a 10psi increase over the spring pressure and it worked fine.

So again, if someone is having trouble with theirs and cant get it to work, i will buy it as mine died in the last fire, and im cheap and cant bring myself to pay new EBC prices when the setup i have now works fine, only it isnt adjustable in the cabin

[justinfox]

Yes I have spoken to my mechanic about it (Indy) and yes we're going to look into the AVCR and even another tune. All good. I'm in no rush as I am sure we'll get it right eventually.