GQ Turbo Fuel Screw

[89_GQTURBO]

Hey all,
just wondering if someone can be clear on the fuel screw, i did a search but i need confirmation...

Which way do you turn the screw to make more fuel hit the motor from the pump... Is it clockwise? I think my car may be running a little lean, i have no smoke what so ever and the exhaust temps seem to be going up to around the 440 degree mark... should i give it a tweak to get a puff of black every now and again, im worried about frying the motor!

Cheers

[hiy6o]

Clockwise 1 flat on the nut at a time dont get it over 550

[thelux]

Diesel is the opposite of petrol. Leaning a petrol car out will make egt's hotter, more fuel will cool. Where as leaning a diesel out will cool it down, richening will heat gasses up. If you richen up your diesel keep an eye closely on your egt's anything above 650 is not safe. Tow a loaded trailer up a hill whilst adjusting and make sure you keep the temp around 600, that way you will have no drama with temps unladen. You can also play with the boost to get yourself a happy medium.

[89_GQTURBO]

so if i go out for a drive today and boot it up hills EGTs should be idea at say 450 or below at 10PSI... Im running a modified GU turbo... its been hi flowed and currently just running a dump pipe as my exhaust needs modification.... Just though id mention too that my Pyro guage probe is before the turbo..

Cheers

[thelux]

Pyro probe should be before turbo always. Yes 450 to 500 maybe 550 under load sounds about right, with a full exhaust though it will be slightly higher as there is more back pressure.

I know this example is a land cruiser but my mates 80 series turbo diesel is running 18PSI with fuel upped to suit and under full load up a hill towing my VL on a car trailer EGT's were 600 which is still safe.

[89_GQTURBO]

..Thanks guys

Have wound it up, its running a hell of alot better now... I had to adjust the idle it was a bit faster after i did it... Its making 13PSI now with only a small turn, still not getting any smoke at all, just a small haze so my guess is itll do till i get my full exhaust sorted.... Gotta say its running a hell of alot harder... EGT seemed to be sitting at 450 at 90 kms an hour full boost... rose very slowly to around 500... gotta say it has been a burst of new life in the old girl

Cheers

[GQ4.8coilcab]

no more then 550 after turbo full load up a hill, 750 degrees before turbo

[89_GQTURBO]

WOW...
ok so my pyro probe is right on the point where air travels into the turbo.. so i can get it up to 750 deg with no dramas? Most things on the internet say 550... That must be after the turbo... so i have a bit of room to play with then... although im not wiling to try and get it up to that temp yet without my exhaust...

Cheers

[coxy321]

750 degrees celcius pre-turbo is a maximum safe peak, as in you can spike it to 750C for a few seconds, however sustained temps that high will eventually damage something, and/or start melting things.

I generally go to 650C as my safe spike temperature as i can't afford to be rebuilding engines at the moment.