Man sorry to hear that. Here is the crazy part. I do not have any internal engine mods done. just bolt-ons. no headers either, just a hooker cat-back exhaust. so engine knock is prolly out the question huh????

I currently have 128k miles on the Z and have never changed the spark plugs, spark plug wires, ignition, or shocks. so maybe in my case it could be anything. I just know that it is frustrating when I am racing someone who has a slower car then me but I still lose because my engine misses at 4,500rpm and up.

This has got to be the biggest problem with z28's besides the window motors.

 

I actually put my lt1 knock module back in to see if it would get rid of the stumble and it didn't help a bit, put the Lt4 module back in and still had the miss. I did the hot cam kit install all at the same time, rockers, cam and springs. I didn't notice the stumble until i had ed wright do the computer tune, i thought he had set the limiter and shift points at the same place so i sent it back and he dropped the shift point 150 rpm but it still did the same thing when i got it back. I have the wiring module already installed with the msd 6al also. I haven't taken it to the track yet but before i was having to let off the gas, let it shift and then nail it again and still ran some high 7's, can't wait to get back to the track to see how much difference it makes in my times. I hope i can run consistent 7.9's and break into the 7.8's with some help from a little cooler air since winter is here!!

 

If you've never changed the plugs, it is time. A few years back, I ran 13.00@106.5. A few months later, I go to the track and run a 13.5 at 103 about 5 times. I can't figure it out. I go to my shop the next day and pulled some plugs. It turned out that the #8 plug was wasted. This plug always seems to go first in these cars. I changed all of the wires and plugs since I had the car on the lift. I went back to the track and was back to 13@106. Start simple, then move on.

With no headers or rockers, I can't see why you'd have any false knock.

 

thats a good run. I have never taken my car to the track but want to as soon as the miss is fixed. What kind of plugs and wires does everyone get? I have heard alot of bad stuff about many of the wire brands.