Redline Motorsports
March 22nd, 2006, 10:47 AM
Got a 00' C5 on the dyno for tuning that we just installed a mild head cam setup on. 222/226 on a 114 with ported heads, LT, 30 # injectors, blah, blah, blah...
The car is pulled 6.9 degrees on KR at 3800 rpms and its just killing the torque curve, as to be expected. The timing is very light as it starts out at 16 degrees at 2300 and is set to provide around 23 degrees at full advance. Just before the knock retard occurs, the timing is 18.5 degrees, hardly enough to cause detonation I feel. We (black02) thought it might have been burst knock in which we eliminated that as an issue.
I then made a pull with 15 degrees on timing across the board and no knock.....and no power!:bawl:
This concludes that it is most likely not a false knock situation. I called the customer to confirm the gas in the car. He claims it is 91+ but also indicated that before he put the car away that he put a fuel stabilizer in the tank. Does any have any thoughts on what the effect of stabilizer has on the octane rating of the fuel? I don't want to chase a ghost if a clean tank of gas solves the problem.
We also richened up the AFR to 12.5:1 to make sure it wasn't a WOT lean situation as well. I typically see these make best power at 13.0:1.
Howard
The car is pulled 6.9 degrees on KR at 3800 rpms and its just killing the torque curve, as to be expected. The timing is very light as it starts out at 16 degrees at 2300 and is set to provide around 23 degrees at full advance. Just before the knock retard occurs, the timing is 18.5 degrees, hardly enough to cause detonation I feel. We (black02) thought it might have been burst knock in which we eliminated that as an issue.
I then made a pull with 15 degrees on timing across the board and no knock.....and no power!:bawl:
This concludes that it is most likely not a false knock situation. I called the customer to confirm the gas in the car. He claims it is 91+ but also indicated that before he put the car away that he put a fuel stabilizer in the tank. Does any have any thoughts on what the effect of stabilizer has on the octane rating of the fuel? I don't want to chase a ghost if a clean tank of gas solves the problem.
We also richened up the AFR to 12.5:1 to make sure it wasn't a WOT lean situation as well. I typically see these make best power at 13.0:1.
Howard