Fuel enconomy

[Lepperfish]

You guys with aftermarket fuel pumps,ECU and injectors running over 200rwkw whats your fuel economy like ?

Does it suck it down, because my R33 is guzzling...

Only 200kms or so for $40.00

Ive been told its to do with the tuning of the car...

Also what ECU's are you using?

Lepperfish... :burnout:

[JimX]

I recently got 12.6L/100km, which was 70km of freeway driving and about 380 of normal city driving. Usually I get low to mid 13's (L/100km) with no freeway driving. Sometimes just over 14 if I have the hammer down a lot or get stuck in a lot of traffic.

If you're getting only 200km out of $40 (which I assume is around 40 litres) then something's very wrong. That is 20L/100km and a lot more than any 200kw Skyline should be getting. I don't think that's a matter of tune but rather a matter of something being wrong, such as the AFM. Get it checked out.

[Gester]

My Economy sucks as well. Normal city driving no long distance trips about 250k a tank then I did an two hours at 100km on the highway with city driving and I got 390km.

Although it seems when I go hard I get better economy? Like if I take it to the strip and do a few runs I get close to 300km a tank. Strange

[benm]

The key to good fuel economy is no sudden accelleration.

You can sit on 110km/h on a freeway all day and do the same fuel mileage as you would doing 60km/h up a busy road with heaps of lights.

Im consistantly up around 420-450km from a full 60L's which isn't -too- bad I guess.

[4door_Sleeper]

Performance car + lead foot +skyine = Poor fuel ecconomy but lots of fun.

If you want ecconomy why not get a push bike?

Compared to the cost of tyres, front mounts, larger turbos, more tyres, the "was that a skyline?" factor, another set of tyres, why worry about the cost of petrol? Its a bit like complaining about the cost of car pollish, -you just GOT TO use it

[Steve]

550cc injectors, bosch 044, power fc, HKS3037 and I got 360km from 50L, but that inlcuded a fair bit of playing and one hour on the dyno. I have never had that bad, ie 200km from 40L, even with a 4 hour dyno tune (same setup), it wasnt that bad, the tune only used 1/2 tank, or a tad under.

So yeah, I reckon you got probs:(

[JimX]

I spoke with Lepperfish in pm about this after having another think, but I'll put up the info here anyway for anyone else with a similar problem.

I had another thought that it might be related to a lack of closed loop mode on his ECU. We're not sure if his aftermarket ECU supports closed loop mode or not, but if not it would explain why he's getting good power but shitty economy when cruising.

Btw, I don't subscribe to the theory that just because it's a performance car it means you have to get bad economy, if I was of that opinion I would have bought a supercharged V8 The whole point of a turbo is you don't have to waste fuel if you don't need to.

[RbHed]

how would u know if ur afm is stuffed ?

my skyline also has poor economy, i get around 300k for a full tank..

[JimX]

Failing AFMs will usually produce bad flat spots as well as bad economy and less than optimal power. Try cleaning it first if you haven't done so. Get some electrical contact cleaner from Jaycar to do this.

[R31Nismoid]

rb25...

walbro pump...

t04e turbo...

chipped ecu

13 psi... mmm... over 200rwkw easily, and i get about 350 to a tank.

Thats with a bit of stick here and there. And crusing mixed into that too.

I'd say if i went easy for a whole tank i could get close to 400km.

If i drive it crazily it's not unbeknown for me to see the underside of 250km's to a tank... that hurts

[R31Nismoid]

fuel regulator is a usual port of call for shit economy (also dirst afm)

if your car blows a fair amount of a fuel cloud behind the car under a bit of a hammer then it's gone.

[Steve]

Those figures I posted above were not running closed loop, ie O2 sensor disabled. I am thinking that perhaps your tune is a bit rich. Wherever you had it tuned, it would be worth taking it somewhere else and just getting them to check AF ratios - at least it would eliminate, or find, one possible cause.

[WLD747]

i fill $35 / 40L of petrol and get 200kms as well i reckon could be afm.

Do you think if i put a z32 afm would be better for economy and responsiveness.

any comments welcome

btw anyone got a z32 afm ? , pm me please

cheers

Ak

[R31Nismoid]

Originally posted by WLD747

i fill $35 / 40L of petrol and get 200kms as well i reckon could be afm.

Do you think if i put a z32 afm would be better for economy and responsiveness.

you cant just 'change' AFM's

you need an a/m ECU or chip to do that dont ya ??

[sfitzy]

I've been doing 12.5l/100kms constantly for the last 6 months, thats for 1/2 city 1/2 freeway driving.... usually reads 340kms with a 1/4 tank left...

[nitemare5]

I can usually rip out 450km (per tank) when it gets down to empty, this about 1/4 freeway driving though.