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hey ALL.

quick question due to expencive fuel price, my car is alway on boost. do i have to do any thing if i turn my boost conrtoler down to say 4psi, another word mostly on vac. its a light modded car with standard ecu.

thanks

depends, is it a stock turbo? the only way to get it to boost so low would be to disconnect the wastegate actuator, and jam the gate fully open. if left connected, it will boost to a minimum of the wastegate actuator spring rate.

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r33 s1, stock ecu,stock turbo, 3"inch cat back zost, pod, 11pis boost.the car does move unless i tap it abit harder but then its in boost so i back of. wat i meant to say was. do i have to reset ecu, regap spark plugss or thins like that if i turn boost down really low until petrol price drop a little. i get 400ks with 50-55 litres when i fill up.

Edited by bluer33
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400km is pretty good though

umm main things to check are the O2 sensor in the exhaust can cause worse economy..

turn the boost back to std 7psi at least.. actuator will allow this..

try a reset on the ecu, also check it for error codes..

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speaking of resetting the ecu, should you reset it when you turn up your boost?

i turned mine up to 10 psi from 4 ..

Im also getting 450kms per tank with 10 psi.. (which seems to be pretty good) ..

Cheers,

-JD

thats what i usedto get at 50km trips each way to and from work..

on 11 psi.. but a fair bit of cruising

currently getting about 13L/100kms with 294rwkw.. so needs a light load tune redone.

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Exactly. You get more boost the more you put your foot down. Just keep the revs lower (dont change above 3000rpm), don't warm up the car longer than 30 sec, anticipating red lights, steady and smooth accelerator control etc can all help.

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lol i love ... untill the fuel prices go down? WE ARE GOING TO GET KILLED BY FUEL PRICES .... it wont go down it will only go up. I payed 1.40 a litre the other day.. when you pay more for a litre of fuel then you do for a litre of milk you know its absolute bullshit. In the few years i have been driving it has gone up almost 60 cents a litre.

Edited by fEkuaR
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paul,

have noticed that the closed loop on the power FC doesn't seem as good as on the std ecu.

when cruising it

A) doesn't bounce the AFR guage as much

B) only seems to do it when slightly accelerating and sits within stoich while holding the throttle in one spot.

C) when holding the throttle in one spot and its not bouncing, increased load on the engine (say a slight hill) it will start working.

not that its running too bad, im at 300km and 1/3 tank left.

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paul,

have noticed that the closed loop on the power FC doesn't seem as good as on the std ecu.

when cruising it

A) doesn't bounce the AFR guage as much

B) only seems to do it when slightly accelerating and sits within stoich while holding the throttle in one spot.

C) when holding the throttle in one spot and its not bouncing, increased load on the engine (say a slight hill) it will start working.

not that its running too bad, im at 300km and 1/3 tank left.

i noticed this too!!!! maybe we should tune the ecu lean and then turn off closed loop mode ?

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The fuel injection map in the ECU is based on airflow load and RPM.

It has nothing to do with boost pressure

boost affects airflow though...

if you wish to turn boost down, unplug the factory boost solenoid and unplug any other boost controller. that way, it will read about 5psi and will never go into 'high' mode.

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whilst you are correct, the throttle pedal decides the final factor.

sure if you run 10psi and full throttle it, its going to chew through lots more air. but thats the throttles fault i would expect (ie: the driver) and not turbocharger boost pressure

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I've noticed that the closed loop on the PowerFC is pretty good. Cruising, accelerating lightly, idling etc, my wideband is always reporting a stoich AFR. I guess it comes down to how close your base map is to stoich! (and the condition of the factory O2 sensor)

Edited by Busky2k
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closed loop should be bouncing the AFR's from lean to stoich.

i think its like 10 times per minute or something, not just sitting in the stoich area on the guage..

i think the condition affects how responsive the unit is.

Bluer33 - safc would allow you to tune the ECU beter for more economy as the std maps are fairly rich when your giving it to the car..

gaps would only help if they are wrong and not the correct gap.. most people run 0.8 for under 1bar of boost.

dont think a dump would help economy too much, except that it would help with power, so less throttle to do the same as before.. so yes it might, as long as your right foot is in check.

Edited by Craved
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