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:lol: "Huger than whatsisname"

Crap weather alright! I was loving the previous few months lack of rain, it's making up for it now though!

The R33 GT-R & GTS25t g/boxes have identical ratios, & to the best of my knowledge share internals? So the RB25DET box should be very strong.

Your economy is typical of a stock ECU'ed (10's A/FR) R33 GTS25t, I use to get ~300-350k per tank pre ECU & A/FR mod's.

Tim (RPM) can do a "fuel press' bleed kit" ($220) to help improve econ' & gain ~10rwkw, the kit will reduce the top end 10:1 A/FR's to 12:1's. Joel has the same kit fitted.

Edit: Looks like Joel beat me to it :P

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Tania (my wife) isn't really a car person to be honest. She doesn't treat cars as a point A to B device but she doesn't really take an active interest either. She doesn't mind going to watch a motorsport event (AIR drags, Le-mans a yr or so back etc...) but it's more to be with me & have a good time rather than the cars :D The few times she has driven the Skyline she's too worried she'll damaged it & I'll be angry @ her (I wouldn't be). I just sit in the passenger seat & say to her, "Go faster!!!", "spin the wheels" :burnout: :P :lol: I think she prefers it when I drive her in the Rav4 or Excel :D

Nice restaurants, good wine/food & friends, weekends away, wine/art-craft festivals, entertaining, travelling the globe, going to the gym, these are the things she likes (me too) ;)

hahah yer.. Julie is that same I tell her go put her foot down..

She doesn't like the way the torque hits especially when only on 1/4 throttle coming out of a corner in second..

I tried to teach her how to launch it but she had troubles as when the turbo kicked in when riding the clutch slowly it would rev straight to rev line but she wouldn't let go of the clutch totally...

Quite funny to watch actually.. :P

Julie used to like driving the V8 better... bah... :D

Phew thank god its normal, def have to get this improved tho , 300km per tank is crazy stuff.

Ok first question what does "A/FR mod's" mean??

And what aftermarket ECU did u get? , I am looking at an Apexi PowerFC but well not for a while due to cost.

This fuel bleed sounds good , how does it work? (spot the Turbo Newbie :P ).

Went for small crusie with the "Jaffa" today , no one was out cruising.

hehe goes very good :P , love that car.

Attracts more attention that mine tho!! hehe.

We are basically even , I can keep my nose ahead of him until about 110 when the V8 torque kicks in and past he goes.

Cool im very keen to find out about this fuel bleed, better econ with more power sounds awsome to me :burnout: :burnout:

A/FR is....

A = Air

F = Fuel

R = Ratio

It's an abbreviation used to describe the composition of the mixture entering the combustion chamber, i.e. 10.5 to 1 ='s 10.5 parts air to 1 part fuel, or 10.5:1. It's not just a turbo term, it's used for any internal combustion engine ;)

Under WOT (wide open throttle) @ full load a forced induction engine will make maximum "safe" power @ ~low 12:1 A/FR. A NA engine is happy even leaner than this due to lower combustion temp's.

From the factory Nissan (in fact most manufacturers) set up very conservative A/FR's to keep everything nice & safe. Rich mixtures mean cooler cylinder temp's, & less chance of Mr "average" filling up with a batch of poor quality low RON fuel & causing engine damage due to pinging, damage that leads to warranty claims for the factory! This explains the usual mid/low 10:1 A/FR's that most GTS25t's run :D

Too lean a A/FR & the cylinder temp's will increase to a point that detonation will occur, just the same as if the inlet air temp is too high (i.e. an inefficent IC)

Provided the inlet temp's are kept down (via a good FMIC) & the timing & fuel is correctly set-up your RB25DET will love 12:1 A/FR, & so will you :P

Mod's to alter the A/FR are things like:

The fuel press' bleed kit. It works by reducing the fuel rail pressure, so less fuel is injected for the same injector opening time (duty cycle).

Aftermarket ECU piggyback modules, Apexi S-AFC/Unichip etc...

An OEM ECU re-tune. Not easily done with the stock R33 ECU.

Full replacement ECU's, Apexi Power FC, Motec etc... This is the best option.

I've got a full replacement "Microtech LT12" ECU.

I'm by no means an automotive guru so the above info shouldn't be take as gospel :D

Matt

Damn thats some mighty fine info and very well explained!!.

Ok so if i get the ECU replaced then do i need this fuel bleed? , or say if i get the fuel bleed and then decide to go a new ecu , do i need to remove the fuel bleed?

All I know is ive gotta improve the fuel econ somehow, or its going to cost me an arm and a leg to keep filling up.

One that note I currently use Ultimate 98, but only prob is there arnt many stations that sell it (West tce, Cnr Sth/henley , and Cnr Anzac/Sth are all i know of), so just wondering if you have ever used the Mobil Premium Unleaded?..... its says 98 ron on the pump but still not sure if its as good as Ultimate 98?

Still cant believe we dont have Optimax here yet, they had it when I was in canberra like nearly 2 years ago now!.

Happy to try & explain as best I can mate :P

If you fit any form of ECU piggyback module, get the stock ECU re-tuned, or replace the stock ECU completely, then a bleed kit (if you'd fitted one) would become redundant :D The f/p bleed can't match a properly tuned electronic management system (any of the above options), except in price!

The f/p bleed kit is the most basic form of fuel control, it's far cheaper than any of the electronic piggyback modules (a 2nd hand Apexi S-AFC or Unichip is ~$350-400? + tuning) The f/p bleed can't provide the scope or flashy options that any of the piggyback set-ups can but it's much better than nothing, & for $220 it's not too bad @ all! As a temp' measure it'll most definitely improve your economy, & gain you ~10rwkw in the process ;)

Basically, fit the f/p bleed until you can afford to do one of the above mentioned ECU upgrade options, then it's a simple matter of removing the bleed (an easy 2min job!) when you do upgrade :D You could probably sell the bleed to someone else.

Unless you're a member of Autospeed you'll only be able to read the first page of this review but it'll help explain the bleed in more detail - http://www.autospeed.com.au/A_1407/page1.html

I've never used Mobil 8000, used only Optimax in NSW, & now only use Ultimate 98. I've read/heard too many bad stories with Optimax!?! I found my plugs would foul very easily on Optimax! I've never had a problem with BP98 yet :D

Here's a list of the BP Ultimate retailers within a 50km radius of Adelaide -

BP West Terrace 41-49 West Terrace Adelaide

BP Express Mile End 95 Henley Beach Rd Mile End

BP Express Glandore 110 Anzac Hwy Glandore

BP Express Glenunga 303 Glen Osmond Rd Glenunga

BP Croydon 231-237 South Road Ridleyton

BP Woodville Park 81 David Terrace Woodville Park

BP Fulham 510 Henly Beach Road Fulham

BP Colonial 232 St Bernards Rd Hectorville

BP Hillcrest 431 North East Road Hillcrest

BP Roseville 125 Grand Junction Road Rosewater

BP Brighton 480-484 Brighton Road Brighton

BP Express Paralowie Cnr Port Wakefield & Bolivar Road Paralowie

BP Express Southern 131 Main South Road Morphett Vale

BP Coastline 35 Gulfview Rd Christies Beach

BP Express Munno Para 43-45 Main North Road Smithfield

Damn u the man for info!!, im sold, Nitrate and I r prob going to RPM sat morning to i will get him to book the car in then.

Im not keen on piggy back stuff, i either go all the way or not at all, so will get a new ecu.

Bleed kit a must tho for sure

Loving that list , how did u manage that?, im printing that out and keeping in the car!

Oh think i worked out what the prob was with car feeling slow etc...

was the fuel , had lost its octane level i think , I filled up with another tank of Ultimate 98 and now back to wheel chirping :(

Damn hate how the fuel goes off!! , I dont drive it enuf to use all the fuel b4 it goes off.

May need to invest in a few bottles of Octane booster.

I had a exh. manifold gasket problem which is fixed now.I think that my clutch problem is me riding it(slack left foot).

Andy-next time you come around Thunder is going to eat you:bonk:

Clint-Hope all goes well with your mods,cant wait to see the outcome.

Drift Spec-Glad to see you havnt written off the car yet:)

Whatsisname-Dont you have anything to do at work?all these long posts:headshot:

Joel-Can you slow down with the mods.I wont be able to keep up

Nitrate-Havnt you heard that your not allowed to cruise with us if you have a GTR:blast: (me jealous)

I hope i didnt miss anyone:shake:

Matt

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