Jump to content
SAU Community

Recommended Posts

  • Replies 242
  • Created
  • Last Reply

Top Posters In This Topic

I filled up on Ultimate (as usual) and added Wynns Injector Cleaner.

Will post results.

Unless my last 1/4 tank lasts way longer than i anticipate, my fuel economy hasnt improved.

i'm looking at prob just over 300km for this tank till it shows just above empty (50L since last fill).

that's a craptacular 16L/100km. wtf?

no freeway driving, all city, short trips, and plenty of boosting.

Edited by Munkyb0y
Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2399500
Share on other sites

man..

how do you guess get so many ks?

i average about 300K for a tank..

and all i got is exhaust.. stock everthing elese..

what's wrong with me car?

how low do u run your fuel gauge? do u let the fuel light come on before u fill up? if not, try that nd see how many more KMs you get off a tank.

In my modified 33 (exhaust/cooler/pod/venting bov) i used to run it ti just under the 1/4 full line and get 300kms, if u run it to fuel light, u will get close to 400kms.

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2411047
Share on other sites

how low do u run your fuel gauge? do u let the fuel light come on before u fill up? if not, try that nd see how many more KMs you get off a tank.

In my modified 33 (exhaust/cooler/pod/venting bov) i used to run it ti just under the 1/4 full line and get 300kms, if u run it to fuel light, u will get close to 400kms.

i run mine till just above empty, but then when i refill it takes 45 - 50 litres.

example, i got 310km on 47Litres (the amount i had to pump to get back to full tank).

that's about 15L/100kms. not too good. ppl here are reporting 11L/100km.

of course if i was doing freeway kms, it would probably be alot better.

anyway, that's the most accurate way to check.

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2414100
Share on other sites

After I put in my highflow cat my fuel consumption has dropped to 10.2L/100km. At the pump it was 440 km of 45 liters with the gauge sitting just below the 1/4 mark. A fair bit of that was freeway to and from uni but I give it a squirt whenever I"m urban driving.

Gotta love the little rb20 :)

Have you checked things like fuel pressure, o2 sensor, injector flow test and crud in the exhaust?

Theres no reason why mildly modded engines wouldn't be able to run close to the factory specs. You just have to keep eliminating things till you get it right.

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2414467
Share on other sites

o2 has been changed. made no difference. but i gotta say, freeway kms make a big difference. i got 380k's off a tank, where 200kms of that was on the freeway. and that's with plenty of boosting.

hmmmm, exhaust, never thought of that. i've got 3inch turbo back. my mechanic told me to try the temp sensor. but u know how it is, all these sensors cost money, and alot of the time, nil results.

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2414916
Share on other sites

o2 has been changed. made no difference. but i gotta say, freeway kms make a big difference. i got 380k's off a tank, where 200kms of that was on the freeway. and that's with plenty of boosting.

hmmmm, exhaust, never thought of that. i've got 3inch turbo back. my mechanic told me to try the temp sensor. but u know how it is, all these sensors cost money, and alot of the time, nil results.

The ECU only uses the o2 sensor when your cruising. As soon as you hit boost or get the revs too high it'll run rich again. Your best bet is probably a tune, they run rich from stock and its probably worse now you've modded it. If your AFR's are around 10-11 instead of 11-12 your going to be using more fuel and making less power.

The temp sensor shouldn't make a difference, as far as I know the ecu just uses it as a warning signal. It might run overly rich if the light is coming on to reduce the temperature, but unless the light is coming on I don't think it'd be causing anything.

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2415000
Share on other sites

The ECU only uses the o2 sensor when your cruising. As soon as you hit boost or get the revs too high it'll run rich again. Your best bet is probably a tune, they run rich from stock and its probably worse now you've modded it. If your AFR's are around 10-11 instead of 11-12 your going to be using more fuel and making less power.

The temp sensor shouldn't make a difference, as far as I know the ecu just uses it as a warning signal. It might run overly rich if the light is coming on to reduce the temperature, but unless the light is coming on I don't think it'd be causing anything.

so how do u tune a stock ecu? with no safc etc?

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2415199
Share on other sites

if you wanna improve your fuel economy a safc2 is the was to go, i went from 180rwhp and 380ks to a tank to 215rwhp and 420 to 450k's / 50l. and that was with increasing boost from stock to 10psi.

this is what makes me worry. you were getting 380kms from 180rwkw before safc.

i'm only getting 300kms from practically stock (3"exhaust, pod).

cleaned afm, changed 02 sensor, new plugs, car runs fine.

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2419900
Share on other sites

  • 3 weeks later...

I Just filled up my car for the first time with the rb26 in and only got 235 kms out of the tank!!

i was shocked my fuel consumption halfed from the rb20. Im still running it in so i wasnt thrashing it. Im running a microtech ecu, is something wrong? do i need to retune or is this the reality of an rb26 running 310 rwhp ?

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2473984
Share on other sites

I just tried some injector cleaner and it seems to have given me a few extra kms. I used to get around 400-420kms before the fuel light came on but yesterday i reached 490kms (r33 gtst)! I used redline SI-1 fuel system cleaner. I also changed the sparkplugs recently so maybe that helped too. anyway im pretty happy with the results as my previous car used to only get me 400kms from a 50l tank and that was a 1.6l!

Haha looks like that was a one off cos ive been getting around 400kms since. Oh well....

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2474052
Share on other sites

Unless my last 1/4 tank lasts way longer than i anticipate, my fuel economy hasnt improved.

i'm looking at prob just over 300km for this tank till it shows just above empty (50L since last fill).

that's a craptacular 16L/100km. wtf?

no freeway driving, all city, short trips, and plenty of boosting.

Yea I am about the same as you - but I do have an auto so I guess I'm going to waste a little more fuel anyway. Still sucks though :(

Link to comment
https://www.sau.com.au/forums/topic/120328-fuel/page/6/#findComment-2474252
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

    • https://www.facebook.com/share/19kSVAc4tc/?mibextid=wwXIfr
    • It would be well worth deciding where you want to go and what you care about. Reliability of everything in a 34 drops MASSIVELY above the 300kw mark. Keeping everything going great at beyond that value will cost ten times the $. Clutches become shit, gearboxes (and engines/bottom ends) become consumable, traction becomes crap. The good news is looking legalish/actually being legal is slighly under the 300kw mark. I would make the assumption you want to ditch the stock plenum too and want to go a front facing unit of some description due to the cross flow. Do the bends on a return flow hurt? Not really. A couple of bends do make a difference but not nearly as much in a forced induction situation. Add 1psi of boost to overcome it. Nobody has ever gone and done a track session monitoring IAT then done a different session on a different intercooler and monitored IAT to see the difference here. All of the benefits here are likely in the "My engine is a forged consumable that I drive once a year because it needs a rebuild every year which takes 9 months of the year to complete" territory. It would be well worth deciding where you want to go and what you care about with this car.
    • By "reverse flow", do you mean "return flow"? Being the IC having a return pipe back behind the bumper reo, or similar? If so... I am currently making ~250 rwkW on a Neo at ~17-18 psi. With a return flow. There's nothing to indicate that it is costing me a lot of power at this level, and I would be surprised if I could not push it harder. True, I have not measured pressure drop across it or IAT changes, but the car does not seem upset about it in any way. I won't be bothering to look into it unless it starts giving trouble or doesn't respond to boost increases when I next put it on the dyno. FWIW, it was tuned with the boost controller off, so achieving ~15-16 psi on the wastegate spring alone, and it is noticeably quicker with the boost controller on and yielding a couple of extra pounds. Hence why I think it is doing OK. So, no, I would not arbitrarily say that return flows are restrictive. Yes, they are certainly restrictive if you're aiming for higher power levels. But I also think that the happy place for a street car is <300 rwkW anyway, so I'm not going to be aiming for power levels that would require me to change the inlet pipework. My car looks very stock, even though everything is different. The turbo and inlet pipes all look stock and run in the stock locations, The airbox looks stock (apart from the inlet being opened up). The turbo looks stock, because it's in the stock location, is the stock housings and can't really be seen anyway. It makes enough power to be good to drive, but won't raise eyebrows if I ever f**k up enough for the cops to lift the bonnet.
    • There is a guy who said he can weld me piping without having to cut chassis, maybe I do that ? Or do I just go reverse flow but isn’t reverse flow very limited once again? 
    • I haven’t yet cut the chassis, maybe I switch to a reverse flow. I’ve got the Intercooler mounted as I already had it but not cut yet. Might have to speak to an engineer 
×
×
  • Create New...