ECMlink still have some knock! please help!

[Sepison]

I've tried to pull some timing off but I can't seem to get the knock completely out, only way is to not boost 26lbs. I am working with a 2g 7 bolt - 850cc injectors -fpr - 272 cams gt35 …please any and all input would be appreciated!

 

[gofer]

A WOT pull means nothing unless you're actually WOT, the throttle position varies from 39% to 94%. If you want a WOT tune then do a WOT pull in 3rd gear from 3k to 7.5k.

The knock you're seeing is nothing, 0.4* is noise the knock sensor is picking up. If you see anything at 2* or more then you need to start doing something to the tune in that area to correct it...

 

[snowborder714]

And at the 0.4* of knock, your wideband is reading extremely lean (13.2:1). Since it looks like you're on gas, this should be addressed. I'd be willing to bet once you get this back up to a more normal AFR (e.g. 11:1), that knock might go away.

Always remember you can reduce knock by making your AFR richer, reducing timing, or turning down boost.

I'd also address your MaxOct fuel table as it has some potentially abrupt AFR changes (e.g. 10.8 to 9.9). Look into dropping one of the Evo tables in to start off with and then adjust and smooth for your target.
evo8v3settings [ECMTuning - wiki]

 

[Sepison]

I see I have this before I made some changes

 

[snowborder714]

That is more significant knock. Although, I would look to your MAF Comp slider tuning and AFR readings before I jump into dropping boost and/or timing.

You can temporarily drop timing via the sliders just to get rid of it if it makes you uncomfortable and then zero out the sliders later and only use the DA timing table for any tuning.

 

[Sepison]

what about this? I did some changes via direct access

 

[snowborder714]

Still have ~2* of knock throughout most of the pull. I personally shoot for 0, but some people are comfortable with anything below 3*.

 

[Sepison]

Still have ~2* of knock throughout most of the pull. I personally shoot for 0, but some people are comfortable with anything below 3*.

Your MAF Comp sliders still need attention.

what should I do in the MAF Comp sliders? thought that once I went SD i didn't have to touch those. How do I adjust what should I look for? Thanks for your help by the way!

 

[snowborder714]

Whoops, missed that you're on SD now. So you have SD values to adjust to get your AFRaitioEst and wideband lines to be on top of each other. The easiest way to do this is to learn how to use LinkTools (built by calan). The SD cell references can be complicated if it shows more than one cell highlighted (using track changes). His tool takes the proper algorithm into account when suggesting changes.

 

[Sepison]

Whoops, missed that you're on SD now. So you have SD values to adjust to get your AFRaitioEst and wideband lines to be on top of each other. The easiest way to do this is to learn how to use LinkTools (built by calan). The SD cell references can be complicated if it shows more than one cell highlighted (using track changes). His tool takes the proper algorithm into account when suggesting changes.

Thank you! I'm looking at it now…what are your thoughts of running E-85 with 850's and raising fuel pressure?

 

[gofer]

You won't be able to squeeze enough fuel out of those 850's on E85 to support your turbo, not a chance. A 35r compressor wheel is capable of flowing up to 65lbs/min which requires AT LEAST a 950cc injector, which you already fall short of, or a 1400cc injector if you plan on squirting E85 to support that airflow.

1400 x 0.67 = 938cc

850 x 0.67 = 570cc​

Your 850's on E85 will flow to the equivalent of a 570cc injector with a BFP of 43.5psi, which can support a turbo flowing ~41lbs/min @ 100% IDC's. The maximum base fuel pressure (BFP) that's recommended is 60psi so doing the math your 570cc injectors (assuming E85) will only stretch to a 670cc injector which still can't support your current turbo.

Here's the calculator I use to determine how far you can stretch injectors using solely fuel pressure adjustments... http://www.deatschwerks.com/resources/fuel-calculators/flow-vs-pressure-calculator


To stretch those 850's to support that turbo on E85 you'll have to turn your BFP up to 120psi...

 

[Sepison]

You won't be able to squeeze enough fuel out of those 850's on E85 to support your turbo, not a chance. A 35r compressor wheel is capable of flowing up to 65lbs/min which requires AT LEAST a 950cc injector, which you already fall short of, or a 1400cc injector if you plan on squirting E85 to support that airflow.

1400 x 0.67 = 938cc

850 x 0.67 = 570cc​

Your 850's on E85 will flow to the equivalent of a 570cc injector with a BFP of 43.5psi, which can support a turbo flowing ~41lbs/min @ 100% IDC's. The maximum base fuel pressure (BFP) that's recommended is 60psi so doing the math your 570cc injectors (assuming E85) will only stretch to a 670cc injector which still can't support your current turbo.


To stretch those 850's to support that turbo on E85 you'll have to turn your BFP up to 120psi...

wow! Ok..guess i'll stay 93 for now! Unless I come across some 1000's!

 

[gofer]

You read it wrong, you need AT LEAST 1400cc injectors if you run E85...