I have a question, I run my truck hard through 1/4 mile and it just knocks a little in 3rd. right as I cross the 1/4 line, The guy helping me tune says take some timimg out and leave the alky the same, I run it on 5, Why just 3rd., Seems to me I should take some more gas out of the pv table and up the alky to say 7 and make a run, It use to kill my et but have it now where it doesn't help or hurt and that sounds like going the wrong way but he knows more than I do, Maybe just playing it safe?
Knocking in 3rd. gear
- Thread starter Double-L
- Start date
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What air fuel and timing is being run?
Any knock is bad.. but a bad tuneup no amount of alky can fix.
Have him call me when tuning, not after :redface:
HTH
Glad you've been reading about PE tables.. now lets see a Wide Band in there to make tuning decisions.
Any knock is bad.. but a bad tuneup no amount of alky can fix.
Have him call me when tuning, not after :redface:
HTH
Glad you've been reading about PE tables.. now lets see a Wide Band in there to make tuning decisions.
Well I am starting to under stand just a little, I have 02's on my laptop but thinking about getting the NGK Powerdex AFX - Air Fuel Ratio Monitor - Wideband o2 , It will read air/fuel ratio but not lambda, I have a few guys that race alky giving me there 2 cents, When the computer shows the 02 knock in 3rd. you can't hear it or feel it, On one run it was after I got out of the throttle, Seems like the alky last forever in the tank, I made three full runs and it droped about two inches in the neck of the tank, Don't know why I am working so hard on this Cotton put a a brand new B.B. 66 turbo put on my 87 Grand National and I haven't even run it yet
Double-L said:
No prob.. if you get knock after you lift, its false knock. false knock is like a bad transmission or motor mount allowing the engine to "bang" against something.. the banging is picked up by the knock sensor and displayed as knock.
Real knock escalates in intensity/severity. In other words once it starts keeps getting worse, and this is what your trying to avoid.
Nothing wrong with beating on the truck.. your enjoying your money
Now getting a wide band will allow you to read air fuel and see where your tuneup is.. and make adjustments. Dont get caught up in the Lambda BS.. when you tune your looking to see what makes more power.. so all you need is a reliable reference. The stock O2 is not very reliable at WOT.Gotta start somewhere and move from there :wink:
Razor said:No prob.. if you get knock after you lift, its false knock. false knock is like a bad transmission or motor mount allowing the engine to "bang" against something.. the banging is picked up by the knock sensor and displayed as knock.
Real knock escalates in intensity/severity. In other words once it starts keeps getting worse, and this is what your trying to avoid.
Nothing wrong with beating on the truck.. your enjoying your money
Gotta start somewhere and move from there :wink:
Well a couple things, I am going to try something on
my next run I keep the truck in 3rd., Next run I am going to kick it in over drive also on the alky we have it tuned running just .18 slower and 1 mph on alky with 21* timming at about 85-90 degrees and no knock, Still tunning but running safe
