How do you check if your COPs are going bad??

[VanWilder]

Well after doing my datalog from 2000-6500 in 4th gear at WOT we noticed at the spot in my dyno that the dip occured not only is my clutch slipping but I'm pulling about 3 degrees of timing. We are completely baffled as to why...Chris sent me a new tune to try tonight that may or may not fix it...we shall see but he said I could be having spark plug blowout which could be caused by my coils starting to go out so I wanted to know how to check each one to either rule it out or find a problem...also it could be pulling timing because the clutch is slipping and causing the load to change thus making the engine pull timing...he tweaked the tune so that if this is the case it wont happen again...hopefully it fixes it but I wanna get a jump start on if it doesnt
Thanks,
-Lance

 

[KenB]

When you say it's pulling 3 degrees of timing...

Do you mean you are seeing 3 degrees of knock retard or do you mean the timing is 3 degrees less than what you are expecting?


Either way spark blowout or a coil going out shouldn't really effect that. I doubt a coil is going, that's not very common.

 

[VanWilder]

When you say it's pulling 3 degrees of timing...

Do you mean you are seeing 3 degrees of knock retard or do you mean the timing is 3 degrees less than what you are expecting?


Either way spark blowout or a coil going out shouldn't really effect that. I doubt a coil is going, that's not very common.

its not pulling timing due to knock sensors at all...during the pull it was right at 30 degrees where it is set to stay at WOT and at the time of the dip in my dyno graph (3800rpm to 5200rpm or so) it drops to 27-28 for whatever reason...we dont exactly know just yet...hopefully Chris from Tillman will step in and clarify anything as to what its exactly doing

 

[KenB]

its not pulling timing due to knock sensors at all...during the pull it was right at 30 degrees where it is set to stay at WOT and at the time of the dip in my dyno graph (3800rpm to 5200rpm or so) it drops to 27-28 for whatever reason...we dont exactly know just yet...hopefully Chris from Tillman will step in and clarify anything as to what its exactly doing

Well that would be in the tune. There are very easy ways to troubleshoot this. I'm sure Chris will handle it.

 

[VanWilder]

Well that would be in the tune. There are very easy ways to troubleshoot this. I'm sure Chris will handle it.

yeah I'm sure he will as well...hopefully the tune I will put on it tonight will clear it up...BTW he is the best tuner I have worked with so far...very easy to get ahold of and he will definately work for you to make things right if something is wrong...definately an A+ in my book...highly recommend him to anyone needing a tune

 

[MikeVistaBlue06]

its not pulling timing due to knock sensors at all...during the pull it was right at 30 degrees where it is set to stay at WOT and at the time of the dip in my dyno graph (3800rpm to 5200rpm or so) it drops to 27-28 for whatever reason...we dont exactly know just yet...hopefully Chris from Tillman will step in and clarify anything as to what its exactly doing

Do you have your knock sensors turned off, if so, just ingore this.

If they are on, then at those rpms you may have something resonating that is faking the knock sensors.

I think mine is doing that when I first tip in the throttle; the sensors are "hearing" something in the Saleen SC that it thinks is knock, and yanks the timing.

HTH

Mike

 

[VanWilder]

Do you have your knock sensors turned off, if so, just ingore this.

If they are on, then at those rpms you may have something resonating that is faking the knock sensors.

I think mine is doing that when I first tip in the throttle; the sensors are "hearing" something in the Saleen SC that it thinks is knock, and yanks the timing.

HTH

Mike

No they arent turned off...here is the email that Chris sent me explaining what it was doing:

"Lance,

I made a few changes to the tune file so now spark is solely dependant upon one table. Just in case something funky was going on. Right where the problem happens, a bunch of timing is yanked out. However, it's not being pulled by the knock sensors, as the spark source never changes and like I told you I limited how much the knock sensors could do anyway. Regardless, the knock sensors are quiet and all of the sudden you're missing a bunch of timing. So with the changes I've made to the tune file, if it still does it you have a mechanical problem. It could be load dropping due to clutch slip, and timing is somehow mechanically affected, but I'm thinking we have some sort of a coil/spark blowout/plug issue. Maybe try throwing the regular plugs back in? Did you use dyelectric grease inside the spark plug boots? Maybe this is a bad coil or boot? I'm not sure. Check and make sure all harnesses are plugged in properly. Something is going on with your timing. Anyway, take another datalog of these exact parameters with the latest tune revision I've sent over to you. If this doesn't fix it, then we need to start looking into a mechanical problem.

Chris Rose
Tillman Speed Inc."