ve pump timing

[trupster415]

what happens when you bump the timeing to much?

 

[DieselSmith]

as far as doing it without removing the pump, its impossible. Most guys have the timing all the way to the head i.e. as far as it will go

 

[trupster415]

as far as doing it without removing the pump, its impossible. Most guys have the timing all the way to the head i.e. as far as it will go

i did that and it ran like crap. it sounded like in was missing under a hard load and it wouldn't boost as much as it did before i bumped the timing.:bang

 

[DieselSmith]

back it off a little, but remember, you're more than likely gonna see less boost when you advance the timing on these dudes

 

[trupster415]

back it off a little, but remember, you're more than likely gonna see less boost when you advance the timing on these dudes

cool thanks. whats better timing or boost. befor i messed with it , it would boost like 38psi and when it ran crappy after i bumped the timing i was lucky to get 30

 

[BC847]

The VE fueled CTD is just like a P7100 fueled CTD.

-> Advancing the injection event allows more time to convert the energy of heat into useful work (pushing the piston).

But it comes at the expense of: Higher peak combustion pressures which threaten head gaskets and such, Higher component temperatures, increased emissions of oxides of nitrogen (pollution), Less torque as the engine is now fighting increased cylinder pressures during the compression stroke, etc.
On the other hand, with the increased combustion pressures, there's a slight increase in apparent horsepower as well as a slight increase in fuel economy, etc.

With using more heat to do actual work in the engine, there's less heat energy being wasted in the exhaust gasses. Said heat is what powers the turbocharger. With that, there's less apparent "boost".

The VE injection pump has the unique feature of dynamic injection event timing. You could think of it as being similar to the ignition advance of a gasser's spark distributor. With increasing engine speed, it's advantageous to advance the spark/injection event.
Just as the gasser's distributor, the VE has a static timing. That you set with positioning the pump (shoved to the head, what ever).

The two are combined in operation. With either means of ignition (Diesel or Otto), you can go too far.

- The main purpose of our advancing the timing over stock with the CTD, is to make better use of the additional fuel provided by bigger injectors, etc. There's only so big a window to inject the fuel relative to top-dead-center of the piston going from the compression stroke to the power stroke, to be most efficient generally speaking.
Changing nothing else, simply slipping in bigger injectors results in a lot more hot, smoky exhaust without notable increases in power. Advancing the injection event allows the increased volume of fuel more time to heat and expand the charge-air, pushing the piston, before it's dumped out the exhaust valve.

@ trupster415

Your description of how crappy it ran after bumping the timing suggests you're running less than big injectors. That's the nature of the beast. Just back it off a little. The loss of boost illustrates that much more heat is staying in the cylinders doing work there.

Remember, boost is merely a measure of resistance of flow through the total engine. It should not be viewed as a measure of power. Slipping in a better flowing cam will result in a drop in boost changing nothing else for example.


Make sense?

 

[Riflemanusmc]

cool thanks. whats better timing or boost. befor i messed with it , it would boost like 38psi and when it ran crappy after i bumped the timing i was lucky to get 30

Take the time and dial in your setup. Porting your exhaust manifold/turbo housing/head. Wrapping your exhaust manifold/turbo housing.

 

[DieselSmith]

as far as your current setup goes, if you are still running the stock turbo, its better to keep the boost down. I know at 30 pounds my stock H1C sounded like a hairdryer, so it seems to me that it would be way out of its efficiency range at 38 pounds.

 

[trupster415]

as far as your current setup goes, if you are still running the stock turbo, its better to keep the boost down. I know at 30 pounds my stock H1C sounded like a hairdryer, so it seems to me that it would be way out of its efficiency range at 38 pounds.

i'm running A HX35W off of a 2000 24v