Engine Knock on 14b 8 pSI?

[92 EcLiPsE]

I have my factory gauge converted to a knock gauge with my DSMCHIPS.COM ECU chip. I was looking at the factory gauge when I was running the car and it read out 5 knock sum at around 4k rpm WOT(needle was at 0, 0=5). Im running 8psi no boost controller, right to the wastegate. Also have the stock sidemount in there. Does that sound right at all to be experiencing knock at that low of boost?


Mods are 680s with compensation
AFC at 0
255 Walbro
Stock 14b and manifold/o2
Aftermarket UICP
Stock LICP

 

[TwoLiterLaser]

Low counts of knock can be caused by a bad sensor, too rich of a fuel trim or some other engine noise being picked up by the knock sensor. How is the top end of your engine? And what kind of compensation are you using with those 680's? You really do not need those injectors with your setup and depending on the fuel pressure you are running you may be rich.

 

[92 EcLiPsE]

WEll I dont have a FPR yet and Im running the stock one. My idle is all over the place because of overrun. Also the knock sensor is brand new. I previously said I have a chip that is compensated for the injectors, dsmchips.com . My next upgrade is the FPR but I dont have any cash right now. THis car isnt my daily driver either so I do a little work to it at a time.
Also I have a 14b thats going in this car with a bullseye housing, ported evo o2 and ported evo manifold. I also have a FMIC waiting to go in. I plan to run around 21-22psi psi on the 14b, thats why I'm using these injectors.

 

[andymoraitis]

Jeff's chips contain stock A/F and timing maps unless you specify something else. That being the case, your factory A/F is still pig rich and your timing curve is nothing special. Try taking some fuel out with the AFC and you should see improvement, however you'll never get it to run right unless you get an AFPR on it.

At the moment, you're likely so rich that you're running into the high 8:1 range, which is enough to trigger rich knock. In addition to that, you're washing fuel past the piston rings and diluting the oil. While taking fuel out with the AFC will lean the car out, it won't correct for the volume issue you have with the 255 and stock FPR.

Go ahead and take fuel out, but the AFPR (as you already know) is a necessity.

Andy

 

[92 EcLiPsE]

Yea that sounds about right with the afpr. I might just throw the N/T regulator on it till I can get an aeromotive or bolton unit. Also gunna hook up the A/F gauge to see what ratio I'm at. Is there anyway to check this in my logger software or on the afc? I haven't really gotten a chance to explore any of there features.

 

[andymoraitis]

The blinky A/F gauge tells you nothing except that the O2 is cycling properly. If you want a real A/F reading, get a wideband or run DSM Link.

 

[kwaliph]

Not to hijack or anything but,

I have almost the same symptoms but with bigger better parts. I have Evo VIII 560cc injectors with a 255 wally and aeromotive afpr set to 38psi bp. I also have the DSMCHIPS.com stage 3 chip for my injectors. At zero correction on the safc, I get 30+ counts of knock running 15 psi. My knock sensor is also brand new. The reason I do not believe I am getting rich knock is because my O2 reading on the logger says .74V at 6500rpms. Last time i checked, thats supermega lean right? How can this be?

My car profile is uptodate for the rest of my mods.

Thanks,
Erik


Edit: I plan strapping on a wideband on later today to see what my A/R is exactly so results will be posted soon.