Upping fuel on a 1HZ turbo

[Baja Burley]

Ive upped the fuel on the main fuel crew 1.5 turns and have a high idle, which I can't drop

Its fitted with a GTurbo from Graeme. EGTS are 500 PRE turbo at a maximum. SO it can handle a lot more fuel but i just cant drop the IDLE on it..

As I said, Main screw is 1.5 turns in, making idle around 1200RPM. I then backed off the minimum screw (idle screw) till it doesnt even touch! I still have idle of about 950RPM..

How do I get more fuel in and drop the idle to 600-700RPM?? I thought of increasing the max fuel screw, while backing off the main screw??

Luke

[crankycruiser]

Not sure bout the Hz, but the dt's also have an "idle damper" screw.

U can adjust idle with this too. It's got a 8mm nut and the stud in the middle has a screw driver slot in it.

Edit: had the nut size wrong.

[crankycruiser]

It's the tiny one on the left of the main fuel screw. I actually think it's an 8mm nut surrounding it.

[dumbdunce]

if you disconnect the linkage does the lever drop to the idle stop? might need to adjust the cable?

[Baja Burley]

Yeah I have disconnected the cable and it falls back to touch the backed off screw, but the idle remains at 950.

Thanks for the detail cranky. I have 3 screws on my pump. The main screw in the middles which actually regulates fuel flow, then two screws either side which simply stop the lever's travel to control minimum and maximum fuel. As I said, the minimum stopper screw is backed so far off, that the lever doesn't touch it.

Who else has fuelled these things up to this level?

[crankycruiser]

No worries mate, I had the same problem with my 1HDT and thats how i fixed it, shame the HZ pump isnt the same!

[Z()LTAN]

1.5 turns!

:O

[hulsty]

I few mates have had this issue too when winding up fuel on N/A pumps. Why get your pump modified to be a turbo pump or find a turbo pump to put on it? Should be able to track down a good used 1HDT/FT pump. Different engine/pump but my factory turbo I have wound the main fuel all the way in with no change to idle at all.

[58bernie]

If the fuel screw is wound in too far which I would suggest is the problem, than back it off CCW, it's sitting up on the high speed governor and that is why you can't back off the rpm at idle. Back it off about 3/4 turn and you will be in roughly a better tune area with AFR anyway.

[SCANAS]

if you disconnect the linkage does the lever drop to the idle stop? might need to adjust the cable?

Is that your first post in years dumbdunce? Where have you been?

[Baja Burley]

What have you cranked yours in Zoltan?
I turned it in 1 whole turn at Graemes instruction. His exact words were; "wind in fuel screw until idle reaches 1100rpm, usually 1 turn, then back off the idle screw to desired idle".. Problem is, it won't back off!

I went another 1/2 of a turn only the other day just to play, is 1.5 turns that crazy?

I'm not really interested in big expensive ball tearing power, I just want the most from what I've got, so I'm not interested in a custom pump..

[Z()LTAN]

Your 1hz pre 07?

Mines late 07 and has larger elements and injectors.

I'm just over 1.5 but have done a lot to lower egts to make it driveable.

[TheBigBoy]

What model 1HZ is it? And where are you located?

[Baja Burley]

It's a '95 80s with factory engine.

I have a HUGE front mont intercooler and at this fuel setting EGT's are very rarely reaching 500*C PRE turbo. So it's well below dangerous.