Turbo 1HZ - Which IP Timing Spec to use? (1 Viewer)

[lelandEOD]

I dabbled today with the IP timing on my rebuild project.

I got the procedure down and made some adjustments to confirm I could get the expected result. But, now I'm at a bit of a crossroads. I'm not sure if I should adjust the IP to the HZ spec, the HDT spec, or somewhere in between?


1HZ - 1.03-1.09mm
1HDT - 1.29-1.35mm

I had the Omega Fuel Injection build the pump as close to 1HDT spec as possible (I sent them a copy of the FSM) Can anyone provide me feedback on which spec I should be using to tune this IP?

for now, I set it to 1.09mm which is the high end of the 1HZ spec. I figured that’d be the safest but I want to hear from you old school diesel tuners.

 

[GTSSportCoupe]

Some of the guys with 3B turbos have broken cranks running stock injection timing. Theory has it that the cylinder pressures were too high with the hotter air and higher pressures. I have not heard of this with a 1HZ, but just keep in mind with hotter air (from turbo compression), cylinder pressure will be higher. Thus retarding the timing a bit from factory spec is probably a good idea on a turbo motor.

On the 2LTE, the ECU retards the timing substantially when intake air temps are high. There is a reason they do this.

 

[davegonz]

Since I didn't mess with the injection pump on my 1HZ, but did turbo it successfully, I would start with the stock timing. I haven't had any issues with one year's worth of driving.

 

[roscoFJ73]

I would go with stock on a new engine. And later if everything is good, have a play with it.

 

[lelandEOD]

Thanks for the replies, fellas. I think keeping it stock is really good advise for a baseline setting. I will ultimately let EGTs and fuel consumption be my guide. My intent is to maximize this engine's useful life to the greatest extent possible so I definitely don't want to do anything to hurt long-term performance.

Thanks so much for the feedback!

 

[SNLC]

FYI, 1999+ 1HZ has a lower timing setting.

I usually set them at the top end of the factory specs, they seem to run best this way.

Cheers

 

[Dougal]

The big difference between 1HD and 1HZ injection timing is due to the direct vs indirect injection. Not the presence of a turbo.

I'd stick with stock timing.

 

[AussieHJCruza]

Don't time an IDI diesel like a DI - seen too many TD42 with rods out the side of the block due to incompetent tuning!

 

[lelandEOD]

The big difference between 1HD and 1HZ injection timing is due to the direct vs indirect injection. Not the presence of a turbo.

I'd stick with stock timing.

This was exactly what I was trying to figure out. Thanks for the replies fellas!!!!