Jump to content
SAU Community

Recommended Posts

I figured Stageas to be heavier on fuel, around the same or slightly more than a turbo Subbie, but at 430km from 64L at mostly motorway/cruising speeds I suspect there is something a miss.....

I'm after some friendly advice to help try to improve things. I've started with new sparkplugs (PLFR5A-11), and have noticed the tailpipe is very sooty (500ish km since it was cleaned)

Thanks in advance,

JP

Link to comment
https://www.sau.com.au/forums/topic/446450-tips-for-improving-fuel-economy/
Share on other sites

This is for the PNM35 right?

The plugs he has used are the correct plugs for the VQ35, probably could have gone for LFR5A-11's rather than the platinum to save coin but doesn't matter.

I recently did around 400km to half a tank in my PNM35 and that was majority highway driving and I'm going to go up north again soon.

PNM35 = no boost. ;)

FWIW I get over 600km before the fuel light in mine if I'm doing open road driving, and that's with zero regard for fuel economy in a country riddled with mountains.

Edited by Hertz Donut

More tyre pressure? What do you guys run anyhow? My placard says 30 front 34 rear, but i run 34 front 36 rear. Tyre wear seems normal.

Dont run anything heavier than a ?W-40 weight oil.

Replace o2 sensor if its stuffed, or if you don't know and want to try it. With consult on an RB its easy to tell, no idea about the more modern (P)NM stuff.

Yeah, some "it's easy on my C34" answers here :D

I don't know what your freeways are like, but I drove mine sydney to melb and back twice in a week. AC on, two people and bags, cursing at about 120 indicated (110) and returned about 10.5/100kms.

The best thing you can do is make sure everything is serviced with correct fluids and filters. Secondly, check tyre pressure, and raise it to 35-37ish. You can take then plenum off and clean it out, they attract a fair bit of blow by oil, and it's good to give it a clean out.

Get it on the freeway with a laptop, and check the O2 sensors are auto correcting the mixture when it's on closed loop.

What fuel you guys have over there? What are you using?

This is for the PNM35 right?

The plugs he has used are the correct plugs for the VQ35, probably could have gone for LFR5A-11's rather than the platinum to save coin but doesn't matter.

I recently did around 400km to half a tank in my PNM35 and that was majority highway driving and I'm going to go up north again soon.

I got the plugs for $8 each from a 350z owner who sold his car before installing

PNM35 = no boost. ;)

FWIW I get over 600km before the fuel light in mine if I'm doing open road driving, and that's with zero regard for fuel economy in a country riddled with mountains.

Geez, you must look after you car well

More tyre pressure? What do you guys run anyhow? My placard says 30 front 34 rear, but i run 34 front 36 rear. Tyre wear seems normal.

Dont run anything heavier than a ?W-40 weight oil.

Replace o2 sensor if its stuffed, or if you don't know and want to try it. With consult on an RB its easy to tell, no idea about the more modern (P)NM stuff.

I'm on Dunlop EnaSaves running about 40psi (49psi is max as stated on the tire)

Yeah, some "it's easy on my C34" answers here :D

I don't know what your freeways are like, but I drove mine sydney to melb and back twice in a week. AC on, two people and bags, cursing at about 120 indicated (110) and returned about 10.5/100kms.

The best thing you can do is make sure everything is serviced with correct fluids and filters. Secondly, check tyre pressure, and raise it to 35-37ish. You can take then plenum off and clean it out, they attract a fair bit of blow by oil, and it's good to give it a clean out.

Get it on the freeway with a laptop, and check the O2 sensors are auto correcting the mixture when it's on closed loop.

What fuel you guys have over there? What are you using?

I'm running BP98. I've cleaned the TB - it was really gunked up. I should really look at changing the diff oils, and add a transcooler, VB, and trans flush.

Could you point me in the dirrection of cables and software needed to connect a laptop?

Any Kiwis know where to source the 02 sensors for a good price?

Thanks,

JP

Geez, you must look after you car well

...

I'm on Dunlop EnaSaves running about 40psi (49psi is max as stated on the tire)

I have a strict policy of changing the oil in our beater Commodore every 80,000km or 8 years, whichever comes last. I'm doing the Stagea every 5,000km/3 months, I don't think it'll handle the same regimen. Other than that I've done nothing with it but it was a mint example when I got it (i.e. before the kids started smearing food and mud into everything and my mother-in-law started parking by Braille).

I'm running Enasaves too, 30-32psi all round and they seem to wear evenly. They're a 55 profile so shouldn't need higher pressures like a 35-40 profile.

It might be different with your car but I get about 100km less out of a tank when using BP than when I use Shell 98

The best way to reduce the amount of fuel you use is put the best in the garage and by a smart kar. The joys of haveing such a nice car (stagea not the smart) also has some draw backs.

If your TB was gummed up, then the rest of the intake will have suffered the same fate. Removal and cleaning of the intake plenum should provide a cleaner intake environment.

I use uprev to do my logging and diagnosis, but they stopped selling just the diagnosis package. Series 2 cars are obdII compliant, so I think you have a fair few options, including some of the android apps and stuff. Somebody might chime in here with what they are using.

Defiantly don't play with the plug gap. This isn't a RB. It's not relevant.

It might be different with your car but I get about 100km less out of a tank when using BP than when I use Shell 98

The best way to reduce the amount of fuel you use is put the best in the garage and by a smart kar. The joys of haveing such a nice car (stagea not the smart) also has some draw backs.

Unfortunately only BP sells 98 in NZ (at least in Christchurch), otherwise its 95 or 91.

I'm not looking for smart-car figures but i'd like to get a little less than 15L/100km (6.8km/L), especially when other stageas are.

If your TB was gummed up, then the rest of the intake will have suffered the same fate. Removal and cleaning of the intake plenum should provide a cleaner intake environment.

Any ideas on how to stop this from happening again once cleaned?

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

    • I got back to Japan in January and was keen to get back on track as quickly as possible. Europe is god-awful for track accessibility (by comparison), so I picked up a first-gen GT86 in December just to have something I could jump into right away. The Skyline came over in a container this time and landed in early January. It was a bit battered after Europe, though—I refused to do anything beyond essential upkeep while it was over there. The clutch master cylinder gave out, and so did the power steering. I didn’t even bother changing the oil; it was the same stuff that went in just before I left Japan the first time. Naughty. Power steering parts would’ve cost double with shipping and taxes, so knowing I’d be heading back to Japan, I just postponed it and powered through the arm workout. It took a solid three months to get the car back on the road. Registration was a nightmare this time around. There were a bunch of BS fees to navigate, and sourcing parts was a headache. I needed stock seats for shaken, mistakenly blew 34k JPY on some ENR34 seats—which, of course, didn’t fit—then ended up having the car’s technical sheet amended to register it as a two-seater with the Brides. Then there’s the GT86. Amazing car. Does everything I want it to do. Parts are cheap, easy to find, and I don’t care what anyone says—it’s super rewarding to drive. I’ve done a few basic mods: diff ratio, coilovers, discs, pads, seat, etc. It already had a new exhaust manifold and the 180kph limiter removed, so I assume it’s running some kind of map. I’ve just been thrashing it at the track non-stop—mostly Fuji Speedway now, since I need something with higher speed after all that autobahn time. The wheels on the R34 always pissed me off—too big, and it was a nightmare getting tires to fit properly under the arches. So I threw in the towel and bought something that fits better. Looks way cleaner too (at least to me)—less hotboy, less attention-seeking. Still an R34, though. Now for future plans. There are a few things still outstanding with the car. First up, the rear subframe needs an overhaul—that’s priority one. Next, I need to figure out an engine rebuild plan. No timeline yet, but I want to keep it economical—not cutting corners, just not throwing tens of thousands at a mechanic I can barely communicate with. And finally, paint. Plus a bit of tidying up here and there.  
    • Nope, needed to clearance under the bar a little with a heat gun, a 1/2" extension as the "clearancer", and big hammer, I was aware of this from the onset, they fit a 2.0 with this intake no problems, but, the 2.5 is around 15mm taller than a 2.0, so "clearancing" was required  It "just" touched when test fitting, now, I have about 10mm of clearance  You cannot see where it was done, and so far, there's no contact when giving it the beans Happy days
    • It's been a while since I've updated this thread. The last year (and some) has been very hectic. In the second-half of 2024 I took the R34 on a trip through Germany, Italy, France and Switzerland - it was f*cking great. I got a little annoyed with the attention the car was getting around Europe and really didn't drive it that much. I could barely work on the car since I was living in an inner-city apartment (with underground parking). During the trip, the car lost power steering in France - split hose - and I ended up driving around 4,000kms with no power steering.  There were a few Nurburgring trips here and there, but in total the R34 amassed just shy of 7,000kms on European roads. Long story short, I broke up with the reason I was transferred to Europe for and requested to be moved back to Japan. The E90, loved it. It was a sunk cost of around EUR 10,000 and I sold it to a friend for EUR 1,500 just to get rid of it quickly. Trust me, moving countries f*cking sucks and I could not be bothered to be as methodical as I was the first time around.
    • I assume clearances were all a-okay?
    • Shock tower brace is in +5Kw....LOL  
×
×
  • Create New...