lag at 3000 RPM

[c20v6turbo3rdgen]

I am having a lag at 2700 and 2900 and then when I get to 3000 the power is alot better. When I am going up hill or if the car is trying ithe whole car jerks hard. I have had that happen in 4th and 5th. I have a LX-i 5 speed if that helps. I don't know what to do. I have put Bosch Plat. 2 plugs and Bosch wires in it. I had someone tell me that the timing was off. He took a timing light on it and then after that he put a bar on the dist. and hit it with a hammer. It worked for a long time and then it started to happen again. I asked him about it and he told me to put some premium in it. I am stumped.

[1988starter]

Check your timing again and make sure it is set right also try premium it helps resist detonation.

[c20v6turbo3rdgen]

what do you mean detonation?

[1988starter]

When gasoline ignites due to compresstion not spark that is why high comp vehicals need high octane or something