Hi im at a loss have misfire full throttle in 4 gear aprox 6.5k.
Changed coil leads plugs, fuel pump checked tank breather, thought was fuel but now maybe electrics.
DO edis units play up? Crank sensor? Lost now! Help!

Fuel flow?
Does your fuel pump have enough flow rate to supply fuel at those revs and load?

I had the same problem on mine a couple of years ago. Same set up, zetec on zx6r carbs. It wasn`t getting enough fuel at high revs causing it to stutter badly. I was running a bike fuel pump and also a malpassi fuel regulator. I removed the fuel regulator which cured it.

Got good fuel flow 1300ml per minute,Car used to rev to 7200 no problem

Whats your AFR at WOT

Does it revs up to 7200??
Or gets to 6.5K only?

I can´t make what you have changed, Coil, leads and plugs?

Does it feels like a rev limiter?

Coil starting to fail may give that failure mode as well as valve float due to weakened spring?
HTH

I’ve changed all electrics 😳
Revs out in lower gears no problem,feels like limiter

I had the same set up and , as mentioned, it was fuel trouble.

I changed all the things you changed chasing it.

Mine was down to crap in the carbs (blocked jet). Quick strip down and plenty of carb cleaner and it was right as rain.

Seems to be fuel trouble one way or another.

Good luck with the fix

Thanks
Dan

Did you use shielded cable for the crank sensor and have earthed it. I had a similar problem but at lower revs with the engine stuttering but this was on injection, it was interference with the crank sensor cable.

Only thing I’ve found is a bit of debris in one of the pilot jets, gonna check the needle valve seat filters to see if blocked up at all. Happy days!

What ECU are you using for ignition?

Megajolt but same problem running just on edis

Are you sure it is not a soft cut out in the megajolt

Yep set at 7500 rpm revs out in lower gears