Jump to content
SAU Community

Recommended Posts

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.

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2105738
Share on other sites

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
Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2105799
Share on other sites

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..

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2105838
Share on other sites

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.

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2105858
Share on other sites

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.

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2105970
Share on other sites

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
Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2105992
Share on other sites

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.

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2106473
Share on other sites

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 ?

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2106889
Share on other sites

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.

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2106982
Share on other sites

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

Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2106996
Share on other sites

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
Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2108612
Share on other sites

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
Link to comment
https://www.sau.com.au/forums/topic/114308-petrol-price/#findComment-2108663
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Ps i found the below forum and it seems to be the same scenario Im dealing with. Going to check my ECU coolant temp wire tomorrow    From NICOclub forum: s1 RB25det flooding at start up Thu Apr 11, 2013 7:23 am I am completely lost on this. Car ran perfectly fine when I parked it at the end of the year. I took the engine out and painted the engine bay, and put a fuel cell with an inline walbro 255 instead of the in tank unit I had last year. After reinstalling everything, the engine floods when the fuel pump primes. if i pull the fuel pump fuse it'll start, and as soon as I put the fuse back in it starts running ridiculously rich. I checked the tps voltage, and its fine. Cleaned the maf as it had some dust from sitting on a shelf all winter, fuel pressure is correct while running, but wont fire until there is less than 5psi in the lines. The fuel lines are run correctly. I have found a few threads with the same problem but no actual explanation of what fixed it, the threads just ended. Any help would be appreciated. Rb25det s1 walbro255 fuel pump nismo fpr holset hx35 turbo fmic 3" exhaust freddy intake manifold q45tb q45 maf   Re: s1 RB25det flooding at start up Fri Apr 12, 2013 5:07 am No, I didn't. I found the problem though. There was a break in one of the ecu coolant temp sensor wires. Once it was repaired it fired right up with no problems. I would have never thought a non working coolant temp sensor would have caused such an issue.
    • Hi sorry late reply I didnt get a chance to take any pics (my mechanics on the other side of the city) but the plugs were fouled from being too rich. I noticed the MAF wasn't genuine, so I replaced it with a genuine green label unit. I also swapped in a different ignitor, but the issue remains. I've narrowed it down a bit now: - If I unplug and reconnect the fuel lines and install fresh spark plugs, the car starts right up and runs perfectly. Took it around the block with no issues - As soon as I shut it off and try to restart, it won't start again - Fuel pressure while cranking is steady around 40 psi, injectors have good spray, return line is clear, and the FPR vacuum is working. It just seems like it's getting flooded after the first start I unplugged coolant sensors to see if its related to ECU flooding but that didnt make a difference. Im thinking its related to this because this issue only started happening after fixing coolant leaks and replacing the bottom part of the stock manifolds coolant pipe. My mechanic took off the inlet to get to get to do these repairs. My mechanics actually just an old mate who's retired now so ill be taking it to a different mechanic who i know has exp with RBs to see if they find anything. If you have any ideas please send em lll give it a try. Ive tried other things like swapping the injectors, fuel rail, different fuel pressure regs, different ignitor, spark plugs, comp test and MAF but the same issue persists.
    • My return flow is custom and puts the return behind the reo, instead of at the bottom. All my core is in the air flow, rather than losing some of it up behind the reo. I realise that the core really acts more as a spiky heatsink than as a constant rate heat exchanger, and that therefore size is important.... but mine fits everything I needed and wanted without having to cut anything, and that's worth something too. And there won't be a hot patch of core up behind the reo after every hit, releasing heat back into the intake air.
    • There is a really fun solution to this problem, buy a Haltech (or ECU of your choice) and put the MAF in the bin.  I'm assuming your going to want more power in future, so you'll need to get the ECU at some stage. I'd put the new MAF money towards the new ECU. 
    • Any idea where I can get genuine MAF apart from used ones? I can't find any only for GTRs and unfortunately that price is not in my budget 🤣 I might gap my plugs down and put my splitfires in, they were only in for a year or so before I started the rebuild 
×
×
  • Create New...