uprated injectors for 2lt Zetec engine
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Virgin
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uprated injectors for 2lt Zetec engine
Can anyone help me, I am currently building a 20lt Zetec (silver top) engine to get about 200BHP out of it. I am having problems identifying any injectors that will go into the original Zetec injector rail (being side fed) are there any injectors that I can use without having to replace the injector rail.
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From: Lisbon
The standard ZETEC inlet only flows enough for around 150 bhp in a NA set up. Unless you are going turbo it will need changing.
You may also fing the injector are positioned far to close to the valves on the standard set up and will restrict max bhp.
Also the ZETEC normally fires the injectors sequentially, if you change to batch fire your injectors will effectively have about twice the capacity over standard.
You may also fing the injector are positioned far to close to the valves on the standard set up and will restrict max bhp.
Also the ZETEC normally fires the injectors sequentially, if you change to batch fire your injectors will effectively have about twice the capacity over standard.
PassionFord Post Troll
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From: Finland
Didn't know N/A was an option 
What you say about the injector capacity doesn't make much sense. An injector flows what it flows, and when they are maxxed, they are 100% of the time open, sequential or batch.
Keep in mind that the zetecs have big choice of inlet manifolds and even teh old aluminum ones come in two different versions. The 1.8 105hp version will flow much less than the 1.8 130hp version. That's something you have not mentioned in your website.
It's a good website by the way.
Ram:
They really are not, although one design is more common than the others, but that's not the case here as we are talking side fed injectors.
What you say about the injector capacity doesn't make much sense. An injector flows what it flows, and when they are maxxed, they are 100% of the time open, sequential or batch.
Keep in mind that the zetecs have big choice of inlet manifolds and even teh old aluminum ones come in two different versions. The 1.8 105hp version will flow much less than the 1.8 130hp version. That's something you have not mentioned in your website.
It's a good website by the way.
Ram:
They really are not, although one design is more common than the others, but that's not the case here as we are talking side fed injectors.
Too many posts.. I need a life!!
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From: Lisbon
Originally Posted by JesseT
Didn't know N/A was an option
What you say about the injector capacity doesn't make much sense. An injector flows what it flows, and when they are maxxed, they are 100% of the time open, sequential or batch.
Ram:
What you say about the injector capacity doesn't make much sense. An injector flows what it flows, and when they are maxxed, they are 100% of the time open, sequential or batch.
Ram:
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PassionFord Post Troll
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From: Finland
Originally Posted by Wardy257
Originally Posted by JesseT
Didn't know N/A was an option
What you say about the injector capacity doesn't make much sense. An injector flows what it flows, and when they are maxxed, they are 100% of the time open, sequential or batch.
Ram:
What you say about the injector capacity doesn't make much sense. An injector flows what it flows, and when they are maxxed, they are 100% of the time open, sequential or batch.
Ram:
Too many posts.. I need a life!!
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From: Lisbon
Some quotes
From Dave Walker
The flow rate of the injector is based on it being open all the time so not relevant. The duty cycle will differ depending on whether it is batch fired or not. As 99% of people do not use sequential injection on aftermarket application them most caculations are designed for batch fired systems.
As rpm increases, the amount of time available to inject the fuel decreases. This is true whether the system is timed to valve opening or batch fired. The batch fired system has the advantage of being able to inject fuel for the entire period of crankshaft rotation whereas the timed system technically only has the time available that the air is flowing in the intake runner. This is determined mainly by the camshaft characteristics. On an average performance cam having 220 degrees of intake duration measured at .050 valve lift, the sequential system has only 61% of the time to inject the fuel as the batch fired system. As such, true, timed, sequential systems must have larger injectors fitted for a given hp.
From Dave Walker
With batch fired injectors some fuel always hangs around in the inlet port waiting for the valve to open. With a sequential system the fuel is only injected during the valve open period and also timed so that none of the fuel follows any air escaping out the exhaust port during the overlap period (all valves open around TDC at the top of the exhaust stroke). That isnt as simple as it sounds.
With a soft, or standard cam, the valve open period is relatively short so you do not have very long to get the fuel injected. When the fuel demand stretches the injection period past the valve open period you end up with the same result as batch firing: fuel hanging around the inlet port waiting for the valve to open again. This means you need a lot of fuel delivery in a short time period if you want to operate truly sequentially.
You can achieve this with bigger flowing injectors, higher fuel pressure, or a combination of both. ............. In theory you have to match your flow rate to the cam duration, not just the overall fuelling requirement.
With a soft, or standard cam, the valve open period is relatively short so you do not have very long to get the fuel injected. When the fuel demand stretches the injection period past the valve open period you end up with the same result as batch firing: fuel hanging around the inlet port waiting for the valve to open again. This means you need a lot of fuel delivery in a short time period if you want to operate truly sequentially.
You can achieve this with bigger flowing injectors, higher fuel pressure, or a combination of both. ............. In theory you have to match your flow rate to the cam duration, not just the overall fuelling requirement.
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Batch and sequentially injected engines produce the more or less same power for the same size injector. I say more or less because you shouldn't run injectors at dutycycles greater than typically 80 - 85% and this is where sequentially injected engines can have the edge over batch fired if the injector rail is too small. This is because you get greater pressure fluctuations that reduce flow on the batch fired system.
Those quotes are misleading because most sequential Ford ecu's start their injection when the inlet valve is closed, so being limited to when the valve is open does not apply. At higher pulsewidths the injectors remain firing until the valve is open.
Those quotes are misleading because most sequential Ford ecu's start their injection when the inlet valve is closed, so being limited to when the valve is open does not apply. At higher pulsewidths the injectors remain firing until the valve is open.
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