AVCR overboost - how the ell do you stop it ??

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Fizzy

AVCR overboost - how the ell do you stop it ??

Post by Fizzy »

I know theres a way to stop it happeneing - can anyone explain it to me - basically to boost a steady 1.5 bar the thing initially shoots round to 1.8 before quickly dropping back - how do I stop this spike ??
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Re: AVCR overboost - how the ell do you stop it ??

Post by MR2Mania »

Fizzy wrote:I know theres a way to stop it happeneing - can anyone explain it to me - basically to boost a steady 1.5 bar the thing initially shoots round to 1.8 before quickly dropping back - how do I stop this spike ??


It doesn't matter WHAT boost level you set the AVCR at, if the duty cycle is too high, it'll overboost. Basically, by setting the boost in the AVCR, you're effectively telling it the LIMIT, which is why you're getting to 1.8bar and then it starts to back off.

To sort this out, drop the duty cycle considerably. What duty cycle is it at the moment?
BenF
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Re: AVCR overboost - how the ell do you stop it ??

Post by BenF »

have a good read of the manual - you need to turn down the inital on-throttle response, or even make it -ve.

Eg if you're in 3rd gear at 4krpms, and the AVCR is set to a 50% duty cycle, and you're seeing 1.8bar spikes initally - you need to change your 3rd start duty cycle to -5% or something, assuming you see these spikes when you boot it in gear?

Be really careful though setting this up - a spike of 5psi on top is really a lot!
Fizzy

Re: AVCR overboost - how the ell do you stop it ??

Post by Fizzy »

Dino - doesnt matter what I set the duty cycle to , it still shoots past it! then drops back - also i aint running it gear specific..
steve b
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Re: AVCR overboost - how the ell do you stop it ??

Post by steve b »

Fizzy wrote:Dino - doesnt matter what I set the duty cycle to , it still shoots past it! then drops back - also i aint running it gear specific..


These sort of hassles got me so pi$$ed of with my AVC-R I put it on ebay after having it for a week.
'02 VX220 2.2 n/a Daily driver - Exige Size TD 1.2 - TAT shorty Diffuser - HardTop - Chris Tullet 4-1 Manifold.

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Re: AVCR overboost - how the ell do you stop it ??

Post by MR2Mania »

steve b wrote:
Fizzy wrote:Dino - doesnt matter what I set the duty cycle to , it still shoots past it! then drops back - also i aint running it gear specific..


These sort of hassles got me so pi$$ed of with my AVC-R I put it on ebay after having it for a week.


Yep, and that's why I always say that, despite the AVCR being probably the best standalone boost controller, it IS a pig to set up properly, but it's great when you've done it! :D

Fizzy, assuming that you've checked all the plumbing and you've not got a leak AFTER the AVCR and before the actuator, let's go through all the settings you have:
What's duty cycle?
What feedback setting do you have?
What gear are you testing in?
Is in-gear learning on?
When you do a run, if you go back into the duty screen, are any of the numbers changed? (ie is learning going on?)
Do you have anything in the start duty for that gear?
Have you actually set up the gear judge, so that it knows what gear you're in?
Mark Edwards
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Re: AVCR overboost - how the ell do you stop it ??

Post by Mark Edwards »

It's the feedback speed you need to play with to get it right. Mine now only spikes by 0.2 each time. Just keep adjusting it bit at a time, it's not a very difficult bit of kit to use once you've learnt it, just takes time.
Fizzy

Re: AVCR overboost - how the ell do you stop it ??

Post by Fizzy »

feedback speed - never heard of it?????
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Re: AVCR overboost - how the ell do you stop it ??

Post by MR2Mania »

Fizzy wrote:feedback speed - never heard of it?????


Mate, go through all the screens, jot down the settings, and then list them out for us. This could be a LOOONG setup though! ;)
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Re: AVCR overboost - how the ell do you stop it ??

Post by Mark Edwards »

Fizzy wrote:feedback speed - never heard of it?????

It's in the settings section, look for F/B speed. Normally you want it on either 3 or 4 but you might have to play with it. The lower the number the slower it reacts, which is normally a good thing.
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Re: AVCR overboost - how the ell do you stop it ??

Post by Graeme Shaw »

I had probs setting up my avcr initially, but once set its awsome!!

Graeme
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