Surging problem Solution

[hitnrun]

Hey everyone thanks for all you replies and suggestions on how to fix the surging, jumpy motion of my car.

This was the problem

When accelerating in any gear, if my right foot is flat it surges/misses (whatever you want to call it) at 4500rpm and agin at around 5000rpm. I have an aftermarket Boost guage, at most rpm it reads ~7psi, when the surging happens (or just before) it reads ~9psi. I can't always get it to hit 9psi only under very heavy load. It then drops down to 0psi and back up again.

All I did was set the timing to 25BTDC. That's it, couldn't believe the power differnece and the smoothness all the way up to redline. It definitely wasn't a boost or fuel cut as I thought. (obviously if you run mad boost you will hit that as well though)

For others with similar problems here are also some very helpful suggestions I received.

Change/clean spark plugs - mine were rooted. Also gap them at 0.8

Take an accurate boost measurement

Airflow metres - sometimes they can stuff up and the cause some major problems.

Once again thanks to DAMQIK for solving the problem and for all the helpful ideas. Keep it up.

Cheers,

Tim