VE pump question

[ajh]

When tuning the VE FIP is the boost compensator in addition to the maximum fuel delivery screw adjustment or is the maximum stop screw the absolute limit to fueling volume?

[reb78]

Most people adjust the boost diaphragm and the see if its necessary to adjust the max fuel screw. I'd have thought that EGT will increase most rapidly with the max fuel adjustment.

Have a read here for more info:

http://forums.lr4x4.com/index.php?showtopic=69119&pid=591801&st=0entry591801

[BogMonster]

My experience is that a tweak on the max fuel screw increases everything but yes this is what sets the overall max - adjusting just the diaphragm just alters the "curve" that it follows as boost increases i.e. will make it increase fuelling earlier at lower boost and improve driveability, though at the cost of extra smoke.

Note that the commonly held belief that once it starts emitting smoke you will not get any more power out of it is not correct, in my early days of fiddling I wound the max fuel screw in about six or eight turns IIRC, the moment you touched the pedal you would have thought there was a warehouse on fire behind you but it was awesome fun I turned it down again quick before I melted a piston though

[dirtydiesel]

When tuning the VE FIP is the boost compensator in addition to the maximum fuel delivery screw adjustment or is the maximum stop screw the absolute limit to fueling volume?

the maximum fuel delivery screw is just that.

The boost aneroid actually reduces fuel delivery under light load and increases fuel delivery according to manifold pressure up to the maximum set by the fuel delivery screw.

The absolute limit to fuel delivery is fuel pressure on the lp side of the pump and plunger size.