davyboy
05-24-2012, 05:45 PM
I am wondering what the stock injectors capability are in a 2001 a4 quattro.
If I remember correctly the stock injectors are 282cc though could be off on that number, has been a long day.
On the ECS website they sell a variety of sizes, stock, 315, 386, 415, 440, 550, 630, 750, and 870.
As a general the ECU should be able to compensate for about a 25% change in flow to prevent running lean or rich.
This however doesn't take into consideration if your system is already running lean (more play) or rich (less play).
If we said the ECU was maxed out in compensation, maxed out lean you'd have a 50% change to play with (going up in injector size) and if maxed out rich, no play at all.
For arguments sake one could say 10% current compensation, you have between 15% and 35% to play with meaning going from stock up to 324cc or 380cc without requiring an immediate tune (not something I would do nor recommend but the idea is that its possible basically meaning a MINOR upgrade to 315 injectors is safe even with only 15% ECU compensation).
This all being said now comes the actual question, what are the stock 282 injectors capable of?
I do have a stock turbo, and this will most likely be the case for at least some months to come if not until next year.
I do have some minor modifications being/been done, airbox delete, samco tip to cone filter, cat delete, cat back exhaust, vac line simplification etc, etc. (it does have revo flash, though I want to remove and replace with unitronics tune would also have that set up for the injectors.
What benefits would I gain with 315cc injectors, and what benefits would I gain with the larger 386cc injectors.
With just minor modifications would it even be worth going up to the 386 injectors, if I do intend to install a K04 turbo, which injectors would be better?
Would either of these (with a correct tune, provide more power, I'm specifically interested in any changes in torque below 2000rpm, and changes to HP and torque in the top of the powerband).
I know I'm asking a lot, however most of what I have read seems to be questions asking small portions about them, never anything as detailed as I am looking for.
This is my first experience with doing these types of modifications, the only of my previous vehicles I modified much was my 94 yukon and that was throttle body injection, so something that I couldn't use experience from there, here lol.
Also as a final note, would the larger injectors cause problems with the K03 turbo as I have heard that it has problems with heat fatigue, would burning more fuel amplify this, (this is also my turbo'd car). Considering simply upgrading a non-turbo'd cars injectors wouldn't benefit it unless there is something to help burn the extra fuel and given that it is a turbo car, I was also interested in if there would be more of a benefit to running larger injectors with a larger turbo (aka if going from stock to 386 with a K03 gave 5% increase in power, would going from stock to 386 with a K04 give 5% as well or would it have a larger gain?)
If I remember correctly the stock injectors are 282cc though could be off on that number, has been a long day.
On the ECS website they sell a variety of sizes, stock, 315, 386, 415, 440, 550, 630, 750, and 870.
As a general the ECU should be able to compensate for about a 25% change in flow to prevent running lean or rich.
This however doesn't take into consideration if your system is already running lean (more play) or rich (less play).
If we said the ECU was maxed out in compensation, maxed out lean you'd have a 50% change to play with (going up in injector size) and if maxed out rich, no play at all.
For arguments sake one could say 10% current compensation, you have between 15% and 35% to play with meaning going from stock up to 324cc or 380cc without requiring an immediate tune (not something I would do nor recommend but the idea is that its possible basically meaning a MINOR upgrade to 315 injectors is safe even with only 15% ECU compensation).
This all being said now comes the actual question, what are the stock 282 injectors capable of?
I do have a stock turbo, and this will most likely be the case for at least some months to come if not until next year.
I do have some minor modifications being/been done, airbox delete, samco tip to cone filter, cat delete, cat back exhaust, vac line simplification etc, etc. (it does have revo flash, though I want to remove and replace with unitronics tune would also have that set up for the injectors.
What benefits would I gain with 315cc injectors, and what benefits would I gain with the larger 386cc injectors.
With just minor modifications would it even be worth going up to the 386 injectors, if I do intend to install a K04 turbo, which injectors would be better?
Would either of these (with a correct tune, provide more power, I'm specifically interested in any changes in torque below 2000rpm, and changes to HP and torque in the top of the powerband).
I know I'm asking a lot, however most of what I have read seems to be questions asking small portions about them, never anything as detailed as I am looking for.
This is my first experience with doing these types of modifications, the only of my previous vehicles I modified much was my 94 yukon and that was throttle body injection, so something that I couldn't use experience from there, here lol.
Also as a final note, would the larger injectors cause problems with the K03 turbo as I have heard that it has problems with heat fatigue, would burning more fuel amplify this, (this is also my turbo'd car). Considering simply upgrading a non-turbo'd cars injectors wouldn't benefit it unless there is something to help burn the extra fuel and given that it is a turbo car, I was also interested in if there would be more of a benefit to running larger injectors with a larger turbo (aka if going from stock to 386 with a K03 gave 5% increase in power, would going from stock to 386 with a K04 give 5% as well or would it have a larger gain?)