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rusty00
19th March 2016, 10:40 AM
Which is the better motors/fuel system for power and fuel usage.
Can someone explain in basic terms how and why one over the other is better in power and fuel usage.
I have read a lot on this but there are so many different views, I was hoping it can be cleared up or at least explained better.

threedogs
19th March 2016, 10:51 AM
The better motor is the CRD,,,,, the Di engine will deliver better fuel fuel figure ,,The CRD will endure higher EGTS.
Both give sprightly performance for a small diesel motor, Its only a 3ltr ZD30 not a LS1 after all
trying to move 2.5t of 4X4 along the road

rusty00
19th March 2016, 11:03 AM
Thanks.
All very well but still looking for more information.
There must be pros and cons for each setup and why they went from one to the other.
If it's not fuel savings for the CDR then was it power?

the evil twin
19th March 2016, 11:15 AM
The change from Di to CRD was mid '07 in Oz when GUIV was replaced bu GUV series
(I had an Aug '07 GUV)

Reduced to the basics the CRD is an improvement over the Di because;
CRD generally gives better power efficiency due to the higher injection pressure and significantly better control of the fuel injection amount and timing
CRD generally allows for greater pollution measures so CRD is still going where Di cannot pass current standards
CRD generally are significantly easier to 'tinker' with fuel control for getting some more zing IE chips, ECU flash etc
ZD30 CRD specifically, the engine will at various times run hotter combustion and higher boost than Di because the engine has more versatile fuel control so the ECU milks it for more performance that it would have lost with antipol tweaks IE the CRD has lower pollution and slight power increase over the Di

Disadvantages;
CRD is very intolerant of dirty fuel and injectors and pumps are expensive to replace.
Individual CRD engines will give wildly varying fuel economy (noone knows why) my CRD easily returned under 11 LPH around town up to 15 LPH towing and an average of 12.5 LPH over the 120,000K I had it (there is an economy thread or two on the Forum).

I would recommend CRD any day with the hope you don't get a thirsty bugger

rusty00
19th March 2016, 11:40 AM
Now we are getting somewhere, thanks for the info.