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Engine Specific Info and Questions => IDI Engine => Topic started by: Thezorn on September 02, 2010, 08:53:45 pm
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I've heard tons about people doing this, but what does it really do? Im guessing I would get alot more fuel because of the much more agressive taper on the pin, but is that it? What type of benifits does this add as to power or effinciency.
I do have one readily availible to swap in, but Im sorta interested as to what it will ACTUALLY do for my car.
Also is this just a plug and play sort of mod? or will there be any Timing/IP tinkering needed?
Thanks,
Will
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Its a drop in mod, will give you more fuel under boost. A friend of mine has it in his AAZ and likes how it can be "tuned" from conservative to aggressive in just 5 minutes.
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okay cool, thats what I was hoping. Im guessing removal and installation is similar or exactly the same on my pump as it is with the 1.6td pump.
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If you haven't played with your pump's fuel screw yet, it's plug and play. If you're already puking a black haze at full throttle, it'll blacken the cloud and you'll need to turn your fueling down to compensate
What it does is increases the difference in fuel from off boost to on boost, by letting the needle that rides on the boost pin run further. It'll help you set your pump up so that you don't have to go so gingerly on the throttle on low boost to keep from throwing black smoke out the back end. It doesn't change how much power you're capable of making though
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So it more or less makes the amount fuel the pump puts out alot more boost responsive?
Will this mean more fuel in high boost ranges? Which is good.
Is this a good mod to do? or will it not change much?
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So it more or less makes the amount fuel the pump puts out alot more boost responsive?
Will this mean more fuel in high boost ranges? Which is good.
Is this a good mod to do? or will it not change much?
Realistically, it means less fuel in low boost ranges. Even without the boost pin, you can turn the max fuel screw in far enough that it will give you however much fuel you wish for. The boost pin is there more to limit your fuel when you don't have boost to burn it up.
It is a good mod to do. Quick and easy and it will certainly be better.
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Alright thats good enough for me then.
Thanks radoTD
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appears to me like we have a new project to take hold of.
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Depending on your particular AAZ pump the returns will vary and you may actually see no gains.
It is my experience with UK pumps, that some are set up so weak that the pin that follows the taper (although fitted) never moves. You could have all the taper in the world - you'll get no extra power.
And then again, I've seen AAZ pumps that will follow a GTD taper completely and then some.
Bosch thought it would also be fun to add in a max stop plate too, this restricts max fuel delivery capacity but it is adjustable externally.
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the pins conical shape allows the pin riding it to move further out and give more travel to the spill collar. aka more fuel injected.
on a bosch pump with a LDA the pin is in control of maximum fuel.
On cummins engines used in Versatile tractor with a BOsch VE pump, the aneroid pin is used to set horsepower.
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Without the proper spring under the LDA diaphram it'll be a smoke show. The stock AAZ spring has a much weaker spring rate than the 1.6's giving way to much fuel at lower RPM & lower boost pressure.
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weak spring eh, I got a new pin for my AAZ haven't put it in yet. Comtemplating building a new motor for it. Its not a 1.6 pin, I'll get a pic up of it, its conical and off center, think its from a Case tractor.
got it at school when I got take these pumps apart! learn and get paid for it!
hahaha