Hi guys, I have a 1985 Corvette with a Miniram, 58mm throttle body, AFR 195 heads, flat tappet zz409 camshaft, 1 5/8" hedman longtube headers, Dynomax true dual exhaust, D.U.I. distributor, MSD 6AL2 ignition box.

What's happening is when I was practicing my launches with the 2 step, I heard the exhaust tone change when I launched.

I took it out yesterday to practice this, I launched the first time. Forgot to turn off the 2 step. So I did it again. This time when I launched, the exhaust tone changed and the car felt like it didn't have as much power. The exhaust got deeper and didn't sound as smooth. The engine didn't rev as smooth either.

I took it out today after I warmed it up. I got gas, took it over to a remote road and tried practicing again. I launched at 2500 RPMs about 2 times with no problem except for tire spin with the 2 step. I then decided I was going to try launching without the 2 step. I launched at 2k RPMs, I bogged down. I launched at 2500 RPMs, I bogged down. I flicked on the 2 step to try again with it set at 2500 RPMs. Launched, spun the tires and then the exhaust changed tone again. After that it didn't rev as smoothly, didn't sound as smooth, and lost a little power.

I pulled it into the garage and was looking around to see if I could see any arcing. I didn't find anything. But I did notice that every half a second the is a jerk on the whole car. It's a small jerk, but I felt it when I had my knee up against the tire.

My injectors are 24 lb injectors from FIC that I got about 8 months ago, I have MSD 8.5mm low resistance ignition wires I put on a month or two ago. D.U.I. distributor and coil and everything I put on a month ago. MSD ignition box was also installed about a month ago.

I'm running NGK BKR6E spark plugs, those were installed about a month ago, they have maybe 100 miles on them. They are gapped at 0.055" as recommended by Davis Unified Ignition.

Has anyone experienced any problems like this before?

Thanks!