Static ignition timing retarding by its self

[JC evo1]

ok this is a strange one, had the car back on the dyno and all was going well it was making good hp until the tuner did another power run and as soon as it came onto boost it was obvious something major was going on as it lost 100whp at 5-5500rpm. Very strange as it was still making the same boost as previous runs, so after a bit if troubleshooting we checked the static ignition timing and it had retarded 12 degrees seemingly by its self. We think we've checked everything mechanical that could cause this, the cam gears havnt slipped, the cas is locked in the same position, remember the early evo motors cas run off the intake camshaft. Everything from the crankshaft to the cas looks fine, so it looks like its something electric causing it.

This isnt the first time it has moved on its own accord, after a previous tuning session i came back and the tuner rechecked the timing before we put it on the dyno and it had retarded 4 degrees, very odd so he reset it back to where it should be but now it has done it again as mentioned above. The car runs a MSD DIS 2, Haltech E6K, something must be going on with one of these but theres no real reason or way it can, got us scratching our heads. So what we've decided to do is im going to drive the car around easy (no boost) for the weekend and recheck the timing next week and see if it has changed again. Really need to find the cause of this before any tuning can be done, imagine if it advanced the timing 12 degrees in a power run, goodbye engine

 

[CLuTZ]

This might sound silly but have you tried another CAS?

 

[JC evo1]

This might sound silly but have you tried another CAS?

we tried a different cas when it was having the ignition cut problem last week, but we havent tried it again for this timing problem, apparently its unlikley that the cas is the prob but i can borrow it again and give it a try. To me it seems like it could be the cas but im no auto electrician or mechanic so my understanding of how it works is basic. Maybe it could be something going on with the msd playing up? We've checked it and all the switches are in the right spot though.

 

[cblancergsr]

did u reset static timing including bridging the wire on the firewall

 

[JC evo1]

did u reset static timing including bridging the wire on the firewall

not sure what you mean, can you explain further?

 

[CLuTZ]

he's talking about the base timing/ static timing settings:

[SIZE=-1] http://www.vfaq.com/mods/wayback/BradBauer/engine/timing.html

But surely you're running an aftermarket ECU though right- Have they set up the aftermarket ignition properly??
[/SIZE]

 

[mannynz]

knock knock

 

[JAP63]

Ensure the Loom and wires are all good. I had something similar years ago, the loom wires had burnt through.