///// Will bigger injectors help fuel economy on NON computer controlled diesels (specifically 7.3 IDI). /////

[Andyinchville1]

Hi All,

Been driving my cargo van (1993 E350 extended cargo van with 7.3 IDI) much more than my TDI lately and it has come to the point where I need to replace injectors (251K miles BUT idled alot by the previous owner so lots more hours on the engine than miles may indicate).

Anyways, in the TDI world (MKIV), bigger injectors and pumps can mean more MPGs IF you keep your foot out of it ...... I was wondering does the same apply to a mechanical diesel (i.e. would bigger injectors get better MPG's on a mechanical diesel OR does that only apply to computer controlled disesels like our TDIs ?).

Thanks in advance for any and all help on this

Andrew

 

[Mozambiquer]

Hi All,

Been driving my cargo van (1993 E350 extended cargo van with 7.3 IDI) much more than my TDI lately and it has come to the point where I need to replace injectors (251K miles BUT idled alot by the previous owner so lots more hours on the engine than miles may indicate).

Anyways, in the TDI world (MKIV), bigger injectors and pumps can mean more MPGs IF you keep your foot out of it ...... I was wondering does the same apply to a mechanical diesel (i.e. would bigger injectors get better MPG's on a mechanical diesel OR does that only apply to computer controlled disesels like our TDIs ?).

Thanks in advance for any and all help on this

Andrew

In my experience with idi diesels with bigger injectors, the fuel economy didn't go up with larger injectors. I put bigger injectors on a 6.5 diesel Chevy and on my idi VW. From what I understand, for better fuel economy on them, simply go with stock sized high quality nozzles set up correctly from a qualified injection shop.
You want the best atomization possible for them.

 

[mech644]

I’d go to ford-trucks.com and visits the pre-power stroke diesel forum. Lots of good info there, one of the few websites that I’ve found that comes close to tdiclub in terms of info and competency of the core members. https://www.ford-trucks.com/forums/forum117/

I’ve been rehabilitating an ‘07 super duty (not diesel though) and have found to a great resource.

 

[Mongler98]

They might, but only if you put more crap around the title of your threads!

 

[TurboABA]

https://www.ford-trucks.com/forums/1058404-getting-maximum-fuel-mileage-mpgs-out-of-your-idi.html

 

[compu_85]

Making sure you have good atomization - which means good injectors, and a good injection pump making maximum pressure, is the way to restore MPGs on any diesel engine.

Like TurboABA's link says, go through the rest of the chassis and be sure it's in tip-top shape. Rolling resistance adds up!

A quick google search shows the 7.3 IDI uses the same type of prechamber as the VW 1.6, which don't suffer from soot buildup like the Mercedes style do.

You should also verify the start of injection timing is set properly, and if there's any timing control devices on that pump that they work correctly too.

-J