Fast vs Dig 6 problems, please help.

[lilthumper]

Ok, After taking my whoopin at the OKC GN shootout, I have been going through the car with a fine comb. After checking or changing almost everything, I had a local buick guy say, " I heard of a compatability issue with the FAST and the Digital MSD's. I then got on the MSD board and the tech guy said, "your problem is in the trigger to the white wire in the MSD box. You need to change your coil charge time to 2.5 ms, this is why your spark is breaking up at 5200 rpm." Now FAST is saying that there engineers aren't buying it and said that they have had no problems with the Digital 6 boxes! I sure would like to keep this brand new DIG 6 instead of going back to the old MSD 6. Has anyone heard of such a problem? Is that FAST guy in here?

 

[Craig Smith]

On a V8, the interval between TDC events of any two adjacent cylinders in the firing order at 6000 RPM is 2.5 mS. This fact alone should shed some light on FAST's doubt about this claim. We have been working with MSD on some compatibility issues with the DIS-4 systems, and I can only guess that the tech you spoke to based his statement on some of the results of the conversations FAST and MSD have had. But the 2.5 mS value you were told about simply cannot be true. If the minimum dwell time really did have to be 2.5 mS, given that there also has to be time for the coil to fire, it wouldn't be possible for the Digital 6 to run a V8 over about 5000 RPM. This is obviously not the case.

I don't know what it is that is causing troubles with your car at the moment but I am sure that this isn't it.

 

[lilthumper]

Yep, he sent me another message saying he meant 680-880 Microseconds, either way, I put my old 6AL and blaster coil on to only have the same problem. Time to keep on looking.