What is actually adjusted on a turbo diesel dyno tune ???

[Hof]

Hi all,

Simple question, as the title says.. I am in the process of fitting a turbo to a TD42 and want to know what is actually done when it is dyno tuned??

This question not only applies to mine but all t/d setups..

I thought only boost and fuel, what else is there??

Cheers,

Hof

[badger]

pump timing

[CWBYUP]

pump timing

Is this all pumps ? Or can only some be adjusted ? Mines a td4.2 with after market turbo on it.

Nick

[Hof]

Yeah I didn't really know they changed the pump timing.. Again for a TD42 would the pump timing be adjusted??

Good question

[rezpkt]

Also 1HZ diesel 80 series with standard pump, is injector pump timeing critical for tuneing an aftermarket turbo or is cranking up the fuel supply sufficient?
Would also like to know what is required and what they do in tuneing a 1HZ diesel at a dyno.

Thanks, Glen

[GQ4.8coilcab]

my understanding of adjusting pump timing (TD42) is manually rotating the pump to advance or retard the timing, but i stand corrected. Fuel is by adjusting a screw.

[badger]

pump timing makes alot more difference than fuel alone
if its timed right (timing should be different for a turbo compared to n/a) it will make more power with less fuel and have better boost responce
also goes along way to keeping egt's low and reliability

[me3@neuralfibre.com]

How do you get pump timing "right" and is it varied with RPM anyway? (1HZ again)?

Thanx
Paul

[udm]

Funny you ask this, i actually checked my 1hz's pump timing today.

It now feels and sounds so different, it feels like it has smoothed up heaps.

I have posted this sometime ago on how to check pump timing, http://www.outerlimits4x4.com/phpBB2/vi ... hp?t=51966 go all the way down the page.

[midi73]

From my understanding of it. Proper pump timing, actually times each pump (each line) individually so that each piston is getting exactly the same amount of fuel. You can then up the fuel without burning out a piston, or using more fuel than necessary. If you just wind up the fuel you will be getting more fuel (obviously), but each cylander still wont be timed to each other.
This reason is also why it is good to get injectors rebuilt, so they can sray even amounts of fuel into each pot. All this is MOST important when adding a turbo to a diesel engine.

[KiwiBacon]

From my understanding of it. Proper pump timing, actually times each pump (each line) individually so that each piston is getting exactly the same amount of fuel. You can then up the fuel without burning out a piston, or using more fuel than necessary. If you just wind up the fuel you will be getting more fuel (obviously), but each cylander still wont be timed to each other.
This reason is also why it is good to get injectors rebuilt, so they can sray even amounts of fuel into each pot. All this is MOST important when adding a turbo to a diesel engine.

You can't time individual cylinders seperately.
Winding up the fuel should not be done without the appropriate instruments. Dyno tuners will probably use an oxygen sensor to work out the air/fuel ratio and max safe exhaust temps from that. Otherwise a pyrometer (EGT Gauge) is mandatory.

[midi73]

From my understanding of it. Proper pump timing, actually times each pump (each line) individually so that each piston is getting exactly the same amount of fuel. You can then up the fuel without burning out a piston, or using more fuel than necessary. If you just wind up the fuel you will be getting more fuel (obviously), but each cylander still wont be timed to each other.
This reason is also why it is good to get injectors rebuilt, so they can sray even amounts of fuel into each pot. All this is MOST important when adding a turbo to a diesel engine.

You can't time individual cylinders seperately.
Winding up the fuel should not be done without the appropriate instruments. Dyno tuners will probably use an oxygen sensor to work out the air/fuel ratio and max safe exhaust temps from that. Otherwise a pyrometer (EGT Gauge) is mandatory.

Ok sorry worded badly. Cant be timmed individually, but each one can be rebuilt or reset so they are pumping evenly.

[KiwiBacon]

Ok sorry worded badly. Cant be timmed individually, but each one can be rebuilt or reset so they are pumping evenly.

Very true, but that would be usually done at pump rebuild time rather than dyno tuning time.

[midi73]

Ok sorry worded badly. Cant be timmed individually, but each one can be rebuilt or reset so they are pumping evenly.

Very true, but that would be usually done at pump rebuild time rather than dyno tuning time.

Ok, yes. Fair enough. Although I have been told it would be a good idea to do it when fitting an after market turbo. Would you agree with this?

[KiwiBacon]

Ok sorry worded badly. Cant be timmed individually, but each one can be rebuilt or reset so they are pumping evenly.

Very true, but that would be usually done at pump rebuild time rather than dyno tuning time.

Ok, yes. Fair enough. Although I have been told it would be a good idea to do it when fitting an after market turbo. Would you agree with this?

I wouldn't expect so.
They should be injecting the same into each cylinder (balanced). There's no reason fitting a turbo would unbalance them or require them to be setup unbalanced.

[GUJohnno]

The Nissan pumps need to be re-done after about 280,000kms.

[midi73]

The Nissan pumps need to be re-done after about 280,000kms.

Yes thankyou that was my point. As they get old they get unbalanced, much the same as injectors wear out unevenly.