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Engine Specific Info and Questions => IDI Engine => Topic started by: vwjunkie53 on May 19, 2011, 01:49:44 pm
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Anyone run these? I know building the pump with a bigger head is going to make the largest improvement, however I'm still working on doing the 12mm pump for my D24T. Right now the stock 10mm head pump is maxed out and I'm running 273 nozzles. With my current turbo/intercooler setup I'm cleaning up all the fuel at 25lbs of boost. The nozzles are advertised as 40hp upgrade for the GM, so I'm hoping I could see a power increase.. Throwing in a set of nozzles is quick and easy compaired to doing a pump, and with a new baby around my free time is limited.
Thanks,
Jason
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owen ran a set of 6.2 or 6.5 nozzles in his VW.. i dont think they were a power increase..
VW nozzles already flow lots of fuel.. more than the engine can burn.
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I wonder if those are the same as military nozzles? HMMW is supposed to be 165HP.
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I am running(and have run in VW's in the past, like the G60 diesel) the GM 6.2 truck nozzles with good results.
no power increase on their own, but they will be able to out-flow the VW ones.
the reason that those are a power increase for a GM motor is that the nozzles were a bottleneck in fueling.
on a VW they are not by a long shot.
-Owen
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candidate for more fuel= how much boost at how many rpms, this is a very important question for me
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candidate for more fuel= how much boost at how many rpms, this is a very important question for me
what are you talking about? what engine? what do you want to know? you dont put bigger injector nozzles in an idi VW its a waste of time. the nozzles are not the bottle neck.. they flow more fuel than the pump is capable of pumping..
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that is all I am trying to find out ROR. not a stupid question considerin that I am pulling all of the stops in my build. The nozzles would flow more fuel than a regular person with a regular turbo at regular boost levels at regular rpms, with a regular pump would be able to pull off, I don't want a bottle neck, that is why the what for.
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ROR is right, I think there are multiple people here with 200+hp and stock nozzles
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sorry, double post.
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cool, so no problem then, no need for aftermarket nozzles of any kind. EVER ;D
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cool, so no problem then, no need for aftermarket nozzles of any kind. EVER ;D
like i said, the injectors flow more fuel than the pump (even a giles pump) is capable of supplying.. all you need is a good, fresh set of nozzles and your good to go.
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There is a lot more to an injector then just the amount of fuel it flows. When it flows how much, and if it has a pre-stream (forget the proper term) are just 2 variables. If flow was all that mattered there wouldn't be hundreds of different injector nozzles.
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I get that, but due to the limited shape of the swirl chamber, and for all intents and purposes, the pattern is adequate . I do however, want to redesign a new type of swirl chamber that utilizes a vaccum design incorporated into it, basically it creates a turbine effect like a small vortex inside the combustion area and the swirl chamber, to better mix the air/fuel. for this a narrow cone shaped spray pattern would be necessary. this would also allow for a more even and thourough burn/flamefront, and be an altogether efficient design reducing emmissions as well. for the purpose of this forum, however, an different nozzle will not produce more power/efficiency, to the best of anyones knowledge.
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basically it creates a turbine effect like a small vortex inside the combustion area and the swirl chamber, to better mix the air/fuel. for this a narrow cone shaped spray pattern would be necessary. this would also allow for a more even and thourough burn/flamefront, and be an altogether efficient design reducing emmissions as well.
a.k.a TDI ;D
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There is a lot more to an injector then just the amount of fuel it flows. When it flows how much, and if it has a pre-stream (forget the proper term) are just 2 variables. If flow was all that mattered there wouldn't be hundreds of different injector nozzles.
well, yea, we need to take into account if if it has the proper shape spray, and since were dealing with a 1.6, there is no need to worry about the pre-injection, because there is none..
thats why like 5 out of the hundreds of nozzles out there work with a VW..
GM prechamber should be shaped pretty similarly to the VW also.. and the 6.2/6.5 never had any sort of pre-injection that im aware of..
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mercedes have a prechamber, where vws have a swirl chamber, isn't this the reason they are not quite compatible, surely mercedes nozzles are proven to work, but i think they have been proven to not be better
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whats the difference between a pre-chamber, and a swirl chamber?
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Classification of indirect combustion chambers (prechambers)
Swirl chamber
It consists of a spherical chamber located in the cylinder head and separated from the engine cylinder by a tangential throat. About 50% of the air enters the swirl chamber during the compression stroke of the engine, producing a swirl. After combustion, the products return through the same throat to the main cylinder at much higher velocity. So more heat loss to walls of the passage takes place. This type of chamber finds application in engines in which fuel control and engine stability are more important than fuel economy. These are Ricardo chambers.
Precombustion chamber
This chamber is located at the cylinder head and is connected to the engine cylinder by small holes. It occupies 40% of the total cylinder volume. During the compression stroke, air from the main cylinder enters the precombustion chamber. At this moment, fuel is injected into the precombustion chamber and combustion begins. Pressure increases and the fuel droplets are forced through the small holes into the main cylinder, resulting in a very good mix of the fuel and air. The bulk of the combustion actually takes place in the main cylinder. This type of combustion chamber has multi-fuel capability because the temperature of the prechamber vaporizes the fuel before the main combustion event occurs.
Air cell chamber
The air cell is a small cylindrical chamber with a hole in one end. It is mounted more or less coaxially with the injector, said axis being parallel to the piston crown, with the injector firing across a small cavity which is open to the cylinder into the hole in the end of the air cell. The air cell is mounted so as to minimise thermal contact with the mass of the head. A pintle injector with a narrow spray pattern is used. At TDC the majority of the charge mass is contained in the cavity and air cell. When the injector fires the jet of fuel enters the air cell and ignites. This results in a jet of flame shooting back out of the air cell directly into the jet of fuel still issuing from the injector. The heat and turbulence give excellent fuel vaporisation and mixing properties. Also since the majority of the combustion takes place outside the air cell in the cavity, which communicates directly with the cylinder, there is less heat loss involved in transferring the burning charge into the cylinder. Air cell injection can be considered as a sort of half way stage between fully indirect and fully direct injection, gaining some of the efficiency advantages of direct injection while retaining the simplicity and ease of development of indirect injection. Air cell chambers are commonly named Lanova air chambers.
Google is really awesome. ;)
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I don't think Google got the swirl chamber air to dead space ratio quite right. Probably closer to 90% IMO. At least they recognise Ricardo's MkV though ;D
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This type of chamber finds application in engines in which fuel control and engine stability are more important than fuel economy. These are Ricardo chambers.
Sounds kind of opposite the 6.2 to me?