push button eco?

[vwjones]

anyone install a shut off solenoid on the boost line between LDA and manifold?  90% of my driving is highway and i'd  like to get better gas mileage.  I'm having thoughts of cruising around with awesome gas mileage but being able to flip a switch and leave silly gassers in billowing clouds of smoke.

[anto]

I used an egr valve to do what you describe but i havent it fitted yet...
Also the ability to tune down the smoke when the peelers/ cops are about is helpful.

[vwjones]

I used an egr valve to do what you describe but i havent it fitted yet...
Also the ability to tune down the smoke when the peelers/ cops are about is helpful.

i'm not familiar with how an EGR valve works.  how do you actuate it?

[burn_your_money]

I don't think that you will see any increase in mileage. Just because the LDA is sensing boost does not mean that the pump is injecting more fuel. Your foot ultimiately controls how much fuel is injected.

[anto]

I used an egr valve to do what you describe but i havent it fitted yet...
Also the ability to tune down the smoke when the peelers/ cops are about is helpful.

i'm not familiar with how an EGR valve works.  how do you actuate it?

12v from battery to egr, earth to egr possibly a fuse and a switch.
egr is simply an air switch. When open the lda will act normally when closed the lda will se no boost there for no boost adjusted fuelling.

[Rabbit on Roids]

anyone install a shut off solenoid on the boost line between LDA and manifold?  90% of my driving is highway and i'd  like to get better gas mileage.  I'm having thoughts of cruising around with awesome gas mileage but being able to flip a switch and leave silly gassers in billowing clouds of smoke.

i dont think you will see better mileage unless you have lots of hills to drive up. i was gonna use an air brake switch for making a "power mode" switch. on one setting, the lda will be off, and it will have stock boost, then flip the switch and it turns the lda on and diverts the wastegate signal to the boost controller. so, one setting will be basically a n/a pump, and the other setting will be turbo pump with more boost.

there are 2 inlets and 3 outlets on my switch. inlet one has an outlet a and outlet b, inlet two has only one outlet.
on one setting, air goes in inlet one and comes out outlet a. flip the switch and it comes out outlet b. the second inlet is just on and off, eihter air flows or doesnt flow.

so, im going to have one signal line going to it, and have the wastegate hooked up to outlet a, then i will have the boost controller hooked up to outlet b. and when outlet b is open, the second inlet and outlet are open, and thats where i will hook up the LDA. so basically the turbo will have a low boost and high boost setting, and the LDA will have an on and off.
anyone see anything wrong with my plans? or did i describe it about as clear as mud?

[vwjones]

I'm with BYM.  Disconnecting the LDA will not help fuel economy at all in cruise situations.  It might help your fuel economy on acceleration if your current LDA adjustment is totally whacked.  Extra boost without fuel to match will hurt overall fuel economy.  Best fuel economy will come from a properly tuned and functioning LDA along with intelligent driving for economy.  A better idea would be a variable wastegate actuator that limits boost (and back pressure) in order to supply the optimal air to fuel for the power demanded without creating excessive back pressure. 

i thought the VW eco diesel was a 1.6 TD without the LDA, only the boost.

[vwjones]

I don't think that you will see any increase in mileage. Just because the LDA is sensing boost does not mean that the pump is injecting more fuel. Your foot ultimiately controls how much fuel is injected.

damn!  I was hoping to find something to control my fuel usage that didn't involve self-control on my part.  I am new to diesel boost and it is waaayyyy fun

[Rabbit on Roids]

keep your boost under 7 psi and you will get mileage. the lower you can keep your boost, the better. because it takes fuel and heat to spool the turbo.

less spoolage = better smileage

[88jetta350]

that's why the first thing that I did was swap in a GTD pump.

[vwjones]

I'm with BYM.  Disconnecting the LDA will not help fuel economy at all in cruise situations.  It might help your fuel economy on acceleration if your current LDA adjustment is totally whacked.  Extra boost without fuel to match will hurt overall fuel economy.  Best fuel economy will come from a properly tuned and functioning LDA along with intelligent driving for economy.  A better idea would be a variable wastegate actuator that limits boost (and back pressure) in order to supply the optimal air to fuel for the power demanded without creating excessive back pressure. 

i thought the VW eco diesel was a 1.6 TD without the LDA, only the boost.

Yes, it was, but the ECOdiesel was not produced to be ECOnomical but rather ECOlogical.  There are several modifications to the ECOdiesel that hurt fuel economy over a "real" 1.6TD including the lack of LDA, an 8mm plunger and head in the injection pump, a catalytic converter.  All of those differences were to reduce emissions at the expense of fuel economy.

you are a wealth of information. thanks for filling us in!

[dts67]

The only way to improve fuel economy imo is to remove emissions controls and optimize your advance system, getting fuel in, in a shorter time span also helps more of it burn. That as well as driving habit.
But, more advance = more nox, watch the trees die behind you!

[88jetta350]

getting fuel in, in a shorter time span also helps more of it burn.

I used to think that and although a shorter injection duration can assist in having more of the fuel burn, it is not necessarily better for fuel economy or for the engine.  Having the injection span more degrees of crank rotation without having the end of the injection too late is actually better.  That's actually one gripe I have with the VE pump.  The injection duration should be determined by the rpm, instead, the ve pump varies the injection duration in order to vary the quantity.  That is also a reason why I wouldn't recommend adding a higher lift camplate or larger plunger unless fueling is going to be increased massively on one of these engines.  Either of those modifications shortens the duration further for a given quantity of fuel.  If the duration using the stock parts cannot deliver enough fuel, then those mods can help, but if the stock parts are still up to the task then changing camplates and heads is detrimental.

So if that's true, what's the point in dropping $700 on a Giles pump, aside from having a rebuilt IP?

[dts67]

Another point I'd like to make is a taller gearbox helped my car incredably, with the old box 70mph was 3100rpm but now 70mph is now about 2450rpm