Rough running above 4,000 revs

[G5FTH]

Hi Everyone,
My engine is running fine at tick over and up to about 4,000 revs on acceleration. After that it all goes wrong.
It feels like it starts misfiring.

I have the Roverguage lead and no fault codes are showing.
Before the misfire (?) I have replaced plugs, leads, ignition module, cap/arm. These were replaced with new items from known TVR sites.
It has also had the vacuum advance replaced as the diaphragm was gone.

Any ideas would be appreciated.

All the best for the New Year!

[Colin RedGriff]

Did you have the problem before you swapped the components over?

If you didn't, I would put the originals back one by one to see if you can resolve it.

I suspect it is probably some sort of ignition problem as the ECU only manages fuel.

Might be something as simple as a connection that has got disturbed which is failing at the higher RPMs

[FlipFlopGriff]

Ignition amp would be my bet.
FFG

[ChimpOnGas]

If the situation only started after you replaced a bunch of ignition components, start putting your old parts back on the car one by one until the issue disappears.

I'd start with the rotor arm

[G5FTH]

Thanks all,
I kept all the parts I took off so I'll swap them back one by one.
Cheers

[mcosh]

Give all the ignition connections good squirt of electrical cleaner, especially around ignition amp.

[G5FTH]

Thanks for the replies.
I cleaned the connections to the ignition amp, still running like a bag of hammers.
I then put the original ignition amp back in and it's running perfect!
Took it out and it's absolutely spot on.
Cheers 😀