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Avc-r Boost Duty

DVS-8OR

By DVS-8OR,
in Engines & Forced Induction

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DVS-8OR Collaborator

DVS-8OR

Posted
Posted

I just installed mine on the weekend. I got a hks2540 on my R33. At first i set it at 30% and i got a boost reading of abt 0.9 bar. I had to set the duty to the lowest it can go (20% duty) and i get abt 0.75 bar. It just doesn't look right with a low duty. I did the tuning in 2nd gear, i read i should do it with 3 rd gear but too afraid to be doing it on public roads as i got caught trying to tune the boost before. Don't want that happening again (not too good for the wallet)

Just wondering what duty other people have it set and if you got a bigger turbo than stock.

Thanks

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https://www.sau.com.au/forums/topic/108476-avc-r-boost-duty/
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dbo Enthusiast

dbo

Posted
Posted

My understanding is that the duty cycle is the time the wastegate stays open/closed.

"Increasing duty cycle increases the length of time that the wastegate remains closed. If you are exceeding your desired boost level than reduce the duty cycle. If you are not achieving your desired boost level or boost falls off after reaching the set point than increase the duty cycle."

(Borrowed from Turbosaturns.net Thank you!)

So, with an HKS 2540 on an RB20DET, i'd say 1 Bar is easily a safe boost level. Try setting your duty cycle to say 35% and see if your getting 1 bar.

I'm guessing you probably have looked at the Turbosaturns.net website. It gives you a brief understanding of how to setup the AVC-R. If you haven't had a look, go check it out as it may help in your situation.

Everyone's Duty cycle should be different for different turbos.

SAMFISHER Enthusiast

SAMFISHER

Posted
Posted (edited)
I just installed mine on the weekend. I got a hks2540 on my R33. At first i set it at 30% and i got a boost reading of abt 0.9 bar. I had to set the duty to the lowest it can go (20% duty) and i get abt 0.75 bar. It just doesn't look right with a low duty. I did the tuning in 2nd gear, i read i should do it with 3 rd gear but too afraid to be doing it on public roads as i got caught trying to tune the boost before. Don't want that happening again (not too good for the wallet)

Just wondering what duty other people have it set and if you got a bigger turbo than stock.

Thanks

What boost do you want to run?

Set the boost you want, go test it. If you don't make your desired boost then increase the duty.

If your max boost reading is over your set boost then decrease the duty. :)

Edited by SAMFISHER
Miller the hoon Rising Star

Miller the hoon

Posted
Posted (edited)

Keeping the waste gate closed 4 to long causes a spike

its a very fine line between a good spool build up and spike with ecu shut down or poping from plug gaps and fuel cut

with no spick u can run higher boost setting

james

Edited by Miller the hoon
Miller the hoon Rising Star

Miller the hoon

Posted
Posted

Is that to help hold boost threw the revs cause i set mine and i dont think it lets you have different duty cyclies but i can floor it and it will hit boost and not move threw gear changes but it is an auto

not even .1 of a psi

james

DVS-8OR Collaborator

DVS-8OR

Posted
  • Author
Posted
What boost do you want to run?

Set the boost you want, go test it. If you don't make your desired boost then increase the duty.

If your max boost reading is over your set boost then decrease the duty. :(

I just want to set a low boost setting, but it seems like the lowest i can get the boost is abt 0.8 bar and thats with the duty set to 20%(lowest it can go).

  • 4 months later...
benm Grand Master

benm

Posted
Posted

I got a new exhaust fitted to my car last week and ever since then my avc-r hasn't been holding boost. The highest it's gone is 1.43 bar on a setting of 1.20 bar (but varies on similar settings) so I really want to fix it up.

My duty cycle is set to 52%, what do I need to adjust to fix the problem?

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