I am wondering if anyone has had issues with knock with their 2.4 the the s/c. I am only running the 2.7" at this time and I have meth and I was seeing 4-6 degrees of knock from 3000-3300rpm (didn't take it any higher due to that). I have a 2.6" to go on but not sure what other people have seen with their setup. I don't know much about tuning or knock so I was hoping to find a few answers before I head back to the dyno to try and finish getting my car tuned. Any help would be appreciated.
Have you desensitized your knock sensor at all in HPTuners? You may want to try lowering the decay rate a bit as the LD9 is pretty notorious for phantom knock. Also you may want to try using some histograms to monitor the actuall knock counts in specific cells which should tell you if it's real or phantom.
President/Founder - 607 Motorsports
jimmyc99z24 wrote:Have you desensitized your knock sensor at all in HPTuners? You may want to try lowering the decay rate a bit as the LD9 is pretty notorious for phantom knock. Also you may want to try using some histograms to monitor the actuall knock counts in specific cells which should tell you if it's real or phantom.
I did not think we could do that. More info.
FU Tuning
Which part? lowereing the decay rate or the histograms? I can't access hptuners here at work so i'm not 100% sure where it's located but you can scale the aggressiveness of the knock sensor down... you can even turn it off entirely if you're confident about your tune.
President/Founder - 607 Motorsports
jimmyc99z24 wrote:Which part? lowereing the decay rate or the histograms? I can't access hptuners here at work so i'm not 100% sure where it's located but you can scale the aggressiveness of the knock sensor down... you can even turn it off entirely if you're confident about your tune.
I was more about desensitized the knock sensor. I knew you could lower the amount of timing it took when it saw knock.
FU Tuning
I'll find the exact location when i'm home and post it up for ya man... like I said if you wanted you could technically turn it completely off. We've turned off sensors on some cars when at the track just so nothing phantom would affect the runs and we were confident with the tunes afr and timing.
President/Founder - 607 Motorsports
My AFR during my 4th gear pull from 3000-3300rpm was between 10.5 and 11.1 if I remember correctly. I am pig rich at this point but have only street tuned it a little bit. Raven was happy with the fuel at this point but wasn't sure why I was have so much knock. So I figured I'd ask around to see if I could find something out that would help him.
I have seen N/A 2.4's with that much knock. What nozzle you running on the meth? What are your IAT's?
FU Tuning
running the 175ml nozzle. IAT between 25 and 30 degrees. I think I am gonna order some one step colder NGK Iridium spark plugs, not sure what the stock number is but I'll have to look around.
25-30 degrees? Is that Celsius? Your IAT's should be at least ambient in low rpms. A mid 11 afr is a good target AFR to shoot for with the GMSC but you definately need to get some full logs from about 3000-redline.
BTW the knock rate is located in the Spark Control ---> Spark Retard ---> Knock Retard Attack ---> Baro Gain and Base Retard
President/Founder - 607 Motorsports
So I ordered some new spark plugs. Not sure if they will help any with the knock but thought it may be worth a try. I went with the NGK TR65IX, they are the iridium ones. I have only done a little research about spark plug gap and am wondering if I lower the gap if it may help with my knock issue? I'm not familiar with timing/spark/tuning so any help would be appreciated.
Get NGK TR6 plugs, not the iridiums...
P&P Tuning
420.5whp / 359.8wtq
Why not the iridiums? Will it be bad that they are iridium. I have already ordered them but if they are going to be not good then I won't get them.
You can get the TR6's at the local parts store ofr about $1.89 a plug.
FU Tuning
Matthew Jollymore wrote:Why not the iridiums? Will it be bad that they are iridium. I have already ordered them but if they are going to be not good then I won't get them.
Heat range..... The TR6's have a lower heat range... Iridiums have a higher heat range...
P&P Tuning
420.5whp / 359.8wtq
I got a one step colder than stock which is what came with the mp45 kit if I am correct. Not sure what is included with the s/c kit but I'm sure the iridium ones are better than the kit spark plugs.
matthew, where did you get ur plugs at and whats the stock number on them? ive been looking for them but nobody can get them around me...
01' Z24 5 speed
422whp/400wtq
T4 Turbocharged
Built LD9
HP Tuners
I just got mine from a small car shop...the stock number is 3692. They were about $16 canadian. I called NGK and got the number and then called around with the stock number and the spark plug number to see where I could get the best deal. Napa has them, car quest did too...canadian tire didn't seem to be able to get them though. Hope that helps.
Iridium's are safe for boost, there not hotter as long as the "6" is in the plug number, but keep in mind, a NGK 6 heat range plug is HALF A NUMBER colder, stock heat range is "55".
With a OD crank pulley AND a 2.6 charger pulley with water injection (better heat killing coefficient) i was running any wear between 26-29* of timing, with 0-2* KR......
I also did the old school SBC trick to the sensor.... Teflon tape.
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
Taetsch Z-24 wrote:Iridium's are safe for boost, there not hotter as long as the "6" is in the plug number, but keep in mind, a NGK 6 heat range plug is HALF A NUMBER colder, stock heat range is "55".
With a OD crank pulley AND a 2.6 charger pulley with water injection (better heat killing coefficient) i was running any wear between 26-29* of timing, with 0-2* KR......
I also did the old school SBC trick to the sensor.... Teflon tape.
Chris
How much boost were u running with that setup?
8-12
Chris
'02 Z-24 Supercharged
13.7 @102.45 MPH Third Place, 2007 GMSC Bash SOLD AS OF 01MAR08
meth inj and coil conversion solved the majority of the knock issues for me
14.82 @ 97 mph
