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I am trying to get my GT35 to boost up more in the midrange. I installed a Apexi AVCR.

Even with the duty cycle set to 90 from 0-5000rpm it only gains goes from 0.6 to 0.75 bar. Surely with a duty cycle of 90 at 5000rpm boost should be skyrocketing? After 5000 I have tapered the duty cycle off since I get boost spiking with the shitting internal gate up to 0.9 bar anyway.

Is my controller stuffed? I have not installed a restrictor in the line, because is didn't say to do it in the instructions. Do I have to install one anyway? I would have thought the restrictor would be inbuilt into the solenoid.

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With the wastegate line disconnected I can get 1 bar by 3500rpm, which is very responsive IMO.

Does anyone have any experience with the AVCR? It has RPM boost mapping and duty cycle mapping. If I set all the duty cycle points to the maximum, I can also get 1 bar by 3500. So you would think that setting all the points at low RPM to max duty cycle then reducing duty cycle as the RPM increase would work. But for some reason when I reduce the duty cycle at high RPM, it also reduces the response so I don't get 1 bar by 3500rpm anymore even though I have max duty cycle up to 5000rpm. WTF?

Edited by DennisRB30

ya I would suggest checking the install first.

what turbo does it run? anyways try say 40 first and see what happens. If it under boosts keep increasing the duty until it it spot on...it may over boost then adjust it down.

If it doesn't work like that something is wrong, its fairly easy to use.

What are you settings for the gear/car etc under settings?

ya I would suggest checking the install first.

what turbo does it run? anyways try say 40 first and see what happens. If it under boosts keep increasing the duty until it it spot on...it may over boost then adjust it down.

If it doesn't work like that something is wrong, its fairly easy to use.

What are you settings for the gear/car etc under settings?

I pulled the solenoid off to bench test it and it was OK so I put it back on. After that it started working somwhat. So maybe I did have the hoses on the wrong way, but it still does't work as well as I had hoped. Maybe I am still doing something wrong?

I'm pretty certain the settings are correct for the car etc and its all hooked up right. Its set to 6 cyl 4 pulse (the car runs a 2JZGTE). All the guages like tacho speedo and throttle read correctly.

I wanted to have a controller with RPM boost mapping so I could dial out the weak midrange associated with boost spiking of my shitty internal gate.

Obviously you can't lower the spike down, but there should be no reason that you can't raise boost in the lower RPM band to match what it spikes to in the top end.

IE, boost spike with full wastegate deflection = 0.9 bar at redline starting from 0.6 bar at 3500rpm. So you don't want a high duty cycle in the top end, but you want a high duty cycle down low that reduces as the revs rise. The SBC can't really cater for this.

I have been setting up the RPM based boost control to try and bring by turbo online as soon as possible. But it does not seem to work. My turbo is capable of reaching 1 bar by 3500 rpm.

So it makes sense that I would pick max duty cycle from 0-3500rpm then reduce it after that. But this does not work! It will still be laggy as. Try and get your head around this.

If I choose max duty cycle from 0-4000 rpm, its still almost exactly as laggy as it was. If I also set the duty cycle at 4500 to 50% and the further RPM points to minimum duty cycle. Boost shoots up around 3500 like I want it to (remember I only changed the 4500rpm point, 3500 was already at max duty) but then it over boosts at 6500rpm, even though from 5000 onward has a minimum duty cycle. So it seems as though it doesn't really do what you tell it in terms of duty cycle per RPM. Adjusting one RPM point seems to effect how it operates in other RPM ranges no where near that point.

Maybe I am doing something wrong. But going by what you's are saying I should just piss it off and get an Eboost 2.

Persevere with AVCR, or piss it off?

dont give up yet.

what turbo is it?

gt3582r-iw or some old school thing?

and can you tell me what port you have the manifold conected to on the solenioid. as this will help.

cheers.

Its of an XR6 turbo. Its a GT35 with a 1.06 rear internal gate. The COM goes to the actuator and the NO goes to the comp cover.

You need to turn down your duty. its way to high, if you have it higher, ur max boost will be lower, because the avc-r is controlling the overboost earlier and earlier. I have an AVCR also, you need to set it to like 52, then work your way up.

Edit Add info.

My mates R34 30k kms, so turbo is new. dont need much duty if turbo is new, if turbo is older, then you need to add duty , to make up for wear ie. allow turbo to work a bit harder.

He had similar issue, but his wouldnt go above .072, and his max boost was set to 1.06 bar and duty to %86. so i took his duty down, to a flat line again, learned gear, then worked it back up from 50% duty. now it boosts to 1bar no problem . If your duty is too high, the AVCR will control the overboost. or possibility to overboost. You can turn this function off, or Turn the function down, so it doesnt control it as much, If you havea read of the manual it explains all this.

cheers.

Edited by silverbulletR33
You need to turn down your duty. its way to high, if you have it higher, ur max boost will be lower, because the avc-r is controlling the overboost earlier and earlier. I have an AVCR also, you need to set it to like 52, then work your way up.

Edit Add info.

My mates R34 30k kms, so turbo is new. dont need much duty if turbo is new, if turbo is older, then you need to add duty , to make up for wear ie. allow turbo to work a bit harder.

He had similar issue, but his wouldnt go above .072, and his max boost was set to 1.06 bar and duty to %86. so i took his duty down, to a flat line again, learned gear, then worked it back up from 50% duty. now it boosts to 1bar no problem . If your duty is too high, the AVCR will control the overboost. or possibility to overboost. You can turn this function off, or Turn the function down, so it doesnt control it as much, If you havea read of the manual it explains all this.

cheers.

Why would having a high duty at low RPM cause overboost at high revs where the duty is set to minimum?

uhh. Ok. Im still learning the system myself. but i just found that if u have it too high, u will not acheive your desired boost.

So what your saying is.. Your not reaching your desired RPM at high revs also?.

also, regarding your first comments. My AVCR is a black model, and the first one i got was faulty. and i had to get a replacement. Now ive been told this isnt a common thing with them, but i guess your one could be also, did ya get it new or second hand??

Also regarding your last question, thats the basic physics of turbos isnt it? higher RPM's make more boost?. which is why u have setup high duty at low rpm, and less duty at high rpm. but say, what duty have you got at say 6k? mine makes the psi i need at only %54.

did you get ur avcr new? or second hand?.

Also might be where you have your actuator controller , mine is COM to Actuator, and NO to intake piping. after intercooler, im honestly just guessing crap now, i am still learning :) maybe if not any of this helps great. otherwise disregard :stupid: good luck wid it mate.

uhh. Ok. Im still learning the system myself. but i just found that if u have it too high, u will not acheive your desired boost.

So what your saying is.. Your not reaching your desired RPM at high revs also?.

also, regarding your first comments. My AVCR is a black model, and the first one i got was faulty. and i had to get a replacement. Now ive been told this isnt a common thing with them, but i guess your one could be also, did ya get it new or second hand??

Also regarding your last question, thats the basic physics of turbos isnt it? higher RPM's make more boost?. which is why u have setup high duty at low rpm, and less duty at high rpm. but say, what duty have you got at say 6k? mine makes the psi i need at only %54.

did you get ur avcr new? or second hand?.

Also might be where you have your actuator controller , mine is COM to Actuator, and NO to intake piping. after intercooler, im honestly just guessing crap now, i am still learning :laugh: maybe if not any of this helps great. otherwise disregard :D good luck wid it mate.

Its used. The duty at 6000 is zero since it boost spikes to 1 bar in the high RPM anyway. This is due to my internal gate being too small. Duty is 90 from 0-4000. Makes 1 bar by 3500. I then taper the duty down sharply toward zero from 4500-6000rpm. The idea being to get 1 bar as quickly as possible without getting more than 1 bar by redline.

Setting the duty up like this should have worked from the beginning, but one of the other features must have been stuffing with it. Maybe the FB speed was causing the inaccuracy with the RPM mapping?

Its used. The duty at 6000 is zero since it boost spikes to 1 bar in the high RPM anyway. This is due to my internal gate being too small. Duty is 90 from 0-4000. Makes 1 bar by 3500. I then taper the duty down sharply toward zero from 4500-6000rpm. The idea being to get 1 bar as quickly as possible without getting more than 1 bar by redline.

Setting the duty up like this should have worked from the beginning, but one of the other features must have been stuffing with it. Maybe the FB speed was causing the inaccuracy with the RPM mapping?

yea could be, some guys have turned theirs off. although i dont recommend doing it :laugh: maybe set to 1 or something.

good luck.

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