Went to Anglesey today looking forward to great day with lots of cool cars and top weather. However on the sighting laps the car jumped out of 3rd twice, both times when under full throttle.

After 8 or 10 "proper" laps we got black flagged due to a loud transmission noise which can only be described as like some dragging their finger nails down a blackboard.

This noise only happens when your off the clutch in 1st, 2nd, 4th, 5th and 6th - not in 3rd ?

Its goes into all gears fine no clunks or crunching.

Anyone got any ideas what this might be, the car recently had a new engine fitted and has a short shifter.
thanks

Yep it drives in all gears

Is that a fairly easy fix or major surgery, i.e. box rebuild ?

Nice one cheers fella

If I was to get another box would anyone have any advice on weather to replace it with a standard 6 box or perhaps go with something else such as a VTS or a 205 bearing in mind it's a track car and acceleration in 2nd, 3rd and 4th is more important that outright top end - I don't recall ever using 6th