Dumping ass loads of fuel into the engine means there is more heat coming out of the motor. On diesels, generally more fuel = more boost. :twisted:
Quote from: "cyrus #1"Dumping ass loads of fuel into the engine means there is more heat coming out of the motor. On diesels, generally more fuel = more boost. :twisted:Indeed.There are a number of us on this board that drive with our turbo's wastegates intentionally disconnected. Peak turbo boost is governed by the position of the max fuel screw on the pump with the wastegate disconnected. That is, the turbo will spool up to whatever pressure the injection pump is dialled to support.I had my max fuel screw set on the pump to allow 20 psi from the turbo at full throttle for a while, now I screwed it back to allow more like 16 - 17 psi at full throttle, and I'm happy.With the max fuel screw turned up, I have to feather the throttle pedal a bit at low engine speed (before boost builds), otherwise I get a bit of black smoke at the tailpipe. But if I wait until the turbo spools up a bit, then I can slam the pedal and there's no smoke at all, just lots of boost pressure & power.
Don't just go straight for the fuel screw and turn the boost up or it will end in tears.
EGT gauge. Boost gauge. EGR delete. Find a pump top with a LDA as the ABL doesn't have one. Fit oil cooler (heavy van, the engines don't last anyway in stock form, messing with one is only going to kill it sooner) Fit intercooler. Start messing with boost and fuel.
The ABL is basically a AAZ with some differences to make it suit in the T4's engine bay, the main ones being that the turbo is mounted at a different angle and therefore uses different manifolds and the pump has no LDA, other than that they are virtually identical in all respects. Anything you can do to an AAZ you can do to an ABL.Id fit a LDA or complete pump straight off a AAZ engine first, then have a play with the boost and fueling.The only problem you may have in fitting an LDA is that I think it would be VERY close and may foul the radiator. Im probably wrong, but it'd be would be worth taking some measurements before investing in a pump or LDA.
Differences between ABL and AAZ that I am aware of...ABL has an extra water outlet on the head, only small, it goes to the header tank.ABL block isn't drilled for a dipstick tube.At some point the valve stem size on the AAZ reduced from 8mm to 7mm, these apparently flow better.I don't think this happened to the ABL and they all have 8mm valve stems.Then, obviously the injection pump.
Dunno about your T4, but I went to fit a boost controller to a mates T4 the other day and was dismayed when I looked under the bonnet and found a tiny turbo and a pump with no LDA.I told him I could get more boost but there really was no point without boost enrichment.I fitted it anyway and he got 15psi no bother - maybe more we didn't try as there just wasn't the fuel there.Loads of room in a T4 bay?? ha ha ha ha ha ha ha ha maybe for turbo access but you try getting to the pump.
Good point. I was thinking more around the turbo and top of the engine!