will going from 550's to 660's mess up a tune?

[90-GST]

a friend has a 2ga tsi awd. he bought it with a big 16g, 550's,etc tuned on dsmlink v2.5. there is a guy that wants to trade him straight up, his FIC 550's for the guy's FIC 660's. if he does the trade, will it mess up the tune he already has? or will he be fine? he doesnt know how to tune link yet and doesnt have the money to pay someone to tune for him. any input?

 

[92AWDHX40]

Well more fuel if its tuned for 500ccs it needs to be adjusted for the larger injectors.

 

[TSiAWD666]

The dead time I'd think would be wrong and resulting a/f would generally be richer requiring adjustment. So basically yes.

 

[Rob10_99]

Even the same brand of injectors, you will need to at least scale it either with global or with fine tuning.
He have a wideband?

 

[92AWDHX40]

You need to tune it with a wideband for accurate measurement.

 

[JusMX141]

With all of the fuel sliders at "0", change the global from approx -18% to approx -30% and the car will at least run.

Dead time may differ, but it's a procedure to straighten out.


Taken right from the DSMLink V2 Users Guide:

The following outlines a good procedure for getting the dead time right for your setup:

1. Car must be fully warmed up then must be operated at cruise for about 10 minutes
followed by idle for 5 minutes to get stable LTFT values.
2. Compare the LTFT at idle and cruise. You want both to be right about zero (+/- 5% or so).
3. If the two are about the same, dead time setting is good.
4. If they are equal but non-zero, adjust the global setting.
5. If idle LTFT is more positive than cruise LTFT, increase the dead time, less,
decrease.


From there it's as simple as using a Wideband to perfect your tune using the fuel sliders. Go leaner until you see knock, add fuel to get rid of knock. Don't touch the timing sliders until you have a firm grasp of the the fuel sliders and how they effect tuning and performance.

 

[sL98-Tsi]

thanks for the help guys.

 

[2gGSX]

It should not change the tune once you have the global/deadtime correctly dialed in, and the fuel trims adjusted for (assuming they were correct in the first place). I moved from 750 to 950cc injectors, and everything was within +.2 according to the wideband.

 

[sL98-Tsi]

It should not change the tune once you have the global/deadtime correctly dialed in, and the fuel trims adjusted for (assuming they were correct in the first place). I moved from 750 to 950cc injectors, and everything was within +.2 according to the wideband.

i don't have a wideband, and i'm still learning about the dsmlink.

 

[2gGSX]

You don't need a wideband--that was just used as an example to show that the WOT tune will still be fairly accurate.

 

[knochgoon24]

i don't have a wideband, and i'm still learning about the dsmlink.

Why don't you have a wideband yet?

 

[Gregory]

This will absolutely mess up the tune. The injectors will flow 18% more fuel. It's also unlikely that just removing 18% fuel globally will get you back to a good tune. You will pretty much have to start from scratch.

 

[JusMX141]

It should not change the tune once you have the global/deadtime correctly dialed in, and the fuel trims adjusted for (assuming they were correct in the first place). I moved from 750 to 950cc injectors, and everything was within +.2 according to the wideband.

How did you go from 750's needing roughly -40% global correction to 950's needing roughly -53% global correction and it didn't change your tune? You should've been pig rich.

If what you're saying is correct, I could rightly put 650's in a customer's car and it will be fine without any correction via AFC or other tuning device.

You don't need a wideband--that was just used as an example to show that the WOT tune will still be fairly accurate.

For a Link Noob, I'd say a wideband is a must. Not having one could be rather costly.

 

[92AWDHX40]

They can be found for a great price at any of our vendors. dsmlink and no wideband?

 

[dsm-onster]

Tune for no knock. Then you won't need a wideband . I have a wideband and it tells me exactly how far I've leaned out before I get knock. But whether or not it's installed, I still get to see how far I can go with the sliders because I have knock retard logged. Set target boost and set target A/F ratio to 10.5 to 11 for pump gas, and then go to town with the timing sliders. Then come back to the fuel sliders. If you're using a 1g or 2g maf, your target will nearly line up perfect with actual during a WOT pull. Thus why the 1g and 2g maf (unhacked) should need no calibration. Advancing timing about 2 degrees perslider is all I wuld do for pumpgas.

In fact, pumpgas philosophy: more power from boost than timing. You can get more power from pump gas, by leaving timing alone and running a relatively higher boost and retarding timing 1-2 degrees at any points in the rpm range where you see knock. If you need to retard timing more than that, then of course your target boost is too high.

 

[DSMunknown]

I think this just solidifies my thoughts around using high-flowing injectors on smaller turbos. Turn up the boost and tune accordingly. Just don't understand why people stick with the 660s for a E316G, for example. No need to worry about boost creep when the turbo is being maxed out. Just doesn't make sense to me.

 

[dsm-onster]

Yes. I think injector size should only be limited by how much control you have. period.

 

[92AWDHX40]

Another reasons for me to get link.

 

[2gGSX]

How did you go from 750's needing roughly -40% global correction to 950's needing roughly -53% global correction and it didn't change your tune? You should've been pig rich.

If what you're saying is correct, I could rightly put 650's in a customer's car and it will be fine without any correction via AFC or other tuning device.



For a Link Noob, I'd say a wideband is a must. Not having one could be rather costly.

I adjusted my global and fine tuned by looking at fuel trims. Why would you think this would not work?

 

[JusMX141]

I adjusted my global and fine tuned by looking at fuel trims. Why would you think this would not work?

I apologize- your initial post made it seem like you went from 750's to 950's and changed nothing.

It seemed like you meant that once you had Global and DT dialed for the smaller injectors you could swap to larger ones without changing anything....and you actually meant in regard to the fuel sliders.