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Hello all, I noticed i have a missing exhaust stud, which would throw out the ecu to rich mode (too much oxygen present)

butttt.... Does the ECU also stay on full rich mode if your open looped with no thermostat installed, or is that only for the Holden Commonwh*res VN onwards ??

I put in bp ultimate 98 full tank, and have barely got 340 km city driving and its just above the line, and i hardly thrashed it .... like i should have.

Any thoughts would be appreciated from knowledged individuals. thanks again!!

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Exhaust would leak out of the manifold father than air being sucked in.

All efi cars run richer when cold. If your car doesn't get up to temp cos it has no thermostat it will run rich.

Talk liters per hundred k's to get a more meaningful consumption figure.

Replace your O2 sensor if you haven't yet.

If you have no thermostat then you are wasting fuel and causing excess damage to your engine from it running too cold all the time. This goes for any car with an ecu.

And as superben said, an exhaust leak will let exhaust gases out, not oxygen in. It will however cause a slight loss of power.

And also as superben said, without knowing your actual economy in L/100kms then it's hard to say whether you are getting poor economy, average economy or just have a dicky fuel gauge.

thanks guys, well i guess the skyline is 60 litres, i filled up what was it, 53 litres, so 53 litres, 340 km

6.4 km to a litre, doesnt sound right does it?

15.625 litres per 100 km , had to rack the brain for a good 30mins to get the equation down pat , LOLLLLLL, i used to be top of the class in algebra too LOOOOOLLLLL!!

Edited by REEMER_31

on another note, i know its not covered here, any-how , i noticed the 5 speed manual and whatever stock diff gears are on the back are not going to cut it, given that i have a 300kph dash read out, and with the current gears it will be near impossible to reach that without 8000 rpm in 5th,

even after the mods im going to do with it, top feed rail + top feed 750 cc injectors, power fc computer, ATR hyper flow turbo,bosch z32 A.F.M / 250 litres per hour fuel pump, adjustable fuel pressure reg with read out gauge and new racing timing belt + water pump tensioner / idler . I want to pull at least 200 in 3rd at max rpm and 300 in 5th at max rpm. what ratio do i need? cheers

Edited by REEMER_31

Different gears aren't going to get you to 300.

Part of a 100k service won't get you there either (you left off cam seals) seems kinda odd you even mentioned it ;)

And whatever turbo that is won't get you to 300 , so you probably should reassess your goal to avoid disappointment.

And cos I'm feeling helpful, you don't need the adjustable regulator.

Your O2 sensor would be screwed, they go bad overtime so just replace it and good luck noticing the difference in economy with a synthetic oil.

on another note, i know its not covered here, any-how , i noticed the 5 speed manual and whatever stock diff gears are on the back are not going to cut it, given that i have a 300kph dash read out, and with the current gears it will be near impossible to reach that without 8000 rpm in 5th,

even after the mods im going to do with it, top feed rail + top feed 750 cc injectors, power fc computer, ATR hyper flow turbo,bosch z32 A.F.M / 250 litres per hour fuel pump, adjustable fuel pressure reg with read out gauge and new racing timing belt + water pump tensioner / idler . I want to pull at least 200 in 3rd at max rpm and 300 in 5th at max rpm. what ratio do i need? cheers

What do you need to pull those speeds in those gears? A 6L Chev motor would be a good start. Unless you like getting beaten of the line by a hyundai excel.

Look at this way, 4th gear won't get to 200kmh on the stock ratios and you want 3rd gear to go faster than 4th. So imaging taking off from a stop in 2nd gear with a big laggy turbo that doesn't make boost until 70kmh. By the time you get to 60kmh the grandma in her corolla that was stopped next to you will be a pair of tail lights in the distance.

And rev limit is the least of your problems when it comes to hitting 300kmh. Aerodynamics plays a major part.

And if you are planning on building your motor with big injectors, turbo, etc then I wouldn't bother about fuel economy because it's only going to get worse with those mods

ahaha , ok back to the original problem at hand, fair enough i wont see those figures of speed with the setup im looking at,

Now i finally realize somehow the ATR HYPERGEAR turbo is not such a "DIRECT BOLT ON " mod after all, somewhere along the lines of external waste gate, * * * F F S inserted here...

Yes i realise another financial downfall is in store to

a> mod the external hypergear turbo to an internal gate,

or b> buy a hi mount manifold with individual hi flow runners etc plus whateever else is needed for the external gate.

the question is, I am not familiar with turbocharged vehicles especially gating systems.

if i buy the 350 dollar stainless high mount manifold, what other expenses am i looking at incurring to change the factory stock setup , baring in mind i have a 250 cigweld welder at my disposal, what is the external gate BS, does is simply mean another bolt on mod to the himount manifold and then hole saw the stock exhaust a lil and weld another pipe in to it, ,

can you break it down for me? thanks guys

on a stock r33 how can i get this new turbo and keep it and buy another manifold and mod the whole car to take this 380kw rated external gate turbo.??? help much appreciated, its obviously going to be a long term project, as i`m sick of the car not being on the road blasting posers as it is.

I would (option C) purchase a hypergear turbo that is a direct bolt on and not f**k about with changing wastegates and manifolds.

I see, the bloke from hypergear is proposing me to re send the external gate to him, and he will fit an internal gate and re ship it for 370 bucks, so it directly bolts on, is this the option C i should take?, because he wont accept item return , not sure if thats legal or not, most people have a return policy ,maybe i overlooked something. When asking why no refund, " such an old model, the *EXTERNAL (EDITED) gated turbos , be worthless to me ", as he built it customly for me ( not sure if thats mentioned in the ebay ad , will build once you pay, but f**k here i am )

Edited by REEMER_31

on a more simpler note, another problem i was facing before fixing the broken exhaust studs and attempting a major performance upgrade was intermittent fuel cut-out or so it seems

you'd plant it or try to plant it (throttle) and hit or miss the engine likes the idea or else it kinda stuttered / missed the mark all together and totally loses power,, I put injector cleaner in it, perhaps i need metho and a miracle also?

is this a

A) blocked fuel filter ?,

B)screwed regulator / and or 's (i notice theres 2 diaphragm units on the r33, one coming up near the fire wall and one on the fuel rail itself,) ?

or

C) fuel lines gunked up from a car that sat around too long before being re-purchased( this one ) ?

Any advice would be good , thanks!

What ecu are you using?

You realise you will need a tuneable ecu, bigger fuel pump and injectors, new clutch etc to get the power you are after?

It's never as easy as bolting on a turbo.

I got the power fc,

750 cc bosch injectors top feed that is

top feed big bore fuel rail

, z32 genuine AFM, ,

, adjustable fuel pressure reg with gauge readout,

new gates water pump +racing timing belt + cam seals, crank seal, tensioner , idler,

the new shit turbo i cant use LOL, ATR HYPERGEAR

255 lph indwelling fuel pump, aftermarket, cost 100 + didnt see the need to buy a bosch, rather take a chance ROFL

guess i need a HD 3 button clutch to live up to the power demand, but heh, im going to bolt the old shit on and just wait around until i can get a clue at the labour / parts i`m looking at here, been a head f**k so far, can only be even more of a head f**k later on LOL !!!

what about the fuel starvation issues, whats the first thing i should change you think?, i re-gapped the spark plugs to 0.8 mm they were over 1.0 gapped causing it to miss on one cylinder, guessing the most gapped cylinder, even at idle, i cured the missing problem re gapping them, but theres a starvation of fuel/air at certain times, doesnt matter what rpm, usually starts when you plant it then it comes good after you settle down, definately seems like it rev limits at 6000 no matter what, and spluttering at those rpms, what am i looking at, bad ecu ? coil pack or simple fuel delivery problems?

all i can say is that its annoying as f**k, i was guessing its the air leak on two of the studs that f**ked the air / fuel ratios on the ecu , but time will tell once i bolt up the stock parts tomorrow

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