Results 1 to 9 of 9

Thread: Knock retard after New Dry Sump system

  1. #1
    Potential Tuner
    Join Date
    Nov 2010
    Posts
    7

    Knock retard after New Dry Sump system

    I have a solid roller ls7 race motor to which I recently added a daileys dry sump system. Now on the dyno it is retarding timing up to 3-4 degrees in some areas. This is on the same tune as before where I had no knock retard. Has anybody seen this before with a dry sump? How can adjust the knock sensors to tune this out?

    Thanks,

    Jerry

  2. #2
    Advanced Tuner
    Join Date
    Oct 2009
    Posts
    321
    how close is the pump mounted to the sensors? it could be picking up a resonance that the ecu reads as knock.

  3. #3
    Potential Tuner
    Join Date
    Nov 2010
    Posts
    7
    The pump is mounted in the stock AC compressor area. Belt driven

  4. #4
    Tuner
    Join Date
    Aug 2010
    Location
    On the third rock from the sun
    Posts
    94
    Put some octane boost and see if it's a false knock. If it is a real knock, go to the spark tables and go to knock sensors. There is ware you'll be able to play with the knock sensors. If your put the mouse courser the Blue and on the bottom of screen is ware it well tell you what each Blues works with.

    Best wishes on the tune and take your time and learn the car with the tuner.

  5. #5
    Advanced Tuner
    Join Date
    Oct 2009
    Posts
    321
    What type of fuel are you running? Was the previous tune right on the edge of the sensor sensitivity? What happens if you pull a couple degrees out of the tune in the area where you are seeing knock?

  6. #6
    Potential Tuner
    Join Date
    Nov 2010
    Posts
    7
    Quote Originally Posted by doc350 View Post
    What type of fuel are you running? Was the previous tune right on the edge of the sensor sensitivity? What happens if you pull a couple degrees out of the tune in the area where you are seeing knock?
    I run 110 leaded fuel. I have removed up to 4 degrees of timing and it still retards. I have never needed to adjust the knock sensors before.

  7. #7
    Potential Tuner
    Join Date
    Oct 2014
    Posts
    1
    Hi jerry did the daileys system improve the hp of the engine on the dyno?

  8. #8
    Advanced Tuner Jabbott's Avatar
    Join Date
    Oct 2006
    Location
    Richmond
    Posts
    223
    Probably not by removing 3-4 degrees. I think you are going to have to knock some sensitivity out of the Knock sensors. Your running race gas right?

  9. #9
    Advanced Tuner
    Join Date
    Oct 2009
    Posts
    321
    with 110 in the tank and no change after removing 4 degrees, I would have to think that you are getting a false knock reading. even something as simple as one of the oil lines for the pump running against the block can cause some weird stuff.