110 V8 not running right

[JumboBeef]

My 110 V8 is not used much, and can often go a week or more without been used.  However, it always starts first turn of the key.

Took it out for a run a few days ago, and everything was fine with starting, tick over and power to pull away.  The problem was when cruising at about 50-60mph in either 4th or 5th gear.  If you tried to accelerate, it *felt* like it was not running on all 8 cylinders: it was very lumpy.  If you eased off the power and just cruised, or stopped and let it tick over, all was fine.  I put it down to damp and thought it would clear.

I took it out yesterday, and got the same problem even though it had a really good drive and was at temperature long enough for any damp to dry out (I assume).

The only thing I have done to it before this problem started was to put my winter radiator muff on (as I do every year).  Surely this would help keep things dry?

Any ideas/suggestions please!

[Landy Andy]

Could it be starvation, enough fuel at low speed but not enough at higher speed?

Andy

[JumboBeef]

Thanks, but I don't think that is it.

It runs fine at any speed/revs, and also under hard acceleration in the lower gears.  The problem only seems to happen at cruising speed when you try to accelerate (slightly) in a high (4th or 5th) gear.

[Range Rover Blues]

I have the same.  Does it purr beautifully or does the exhaust note "chug " just a little at idle?  if the later do a comp test, you might have burned a valve.

[JumboBeef]

Thanks for the replies: I'm now convinced it is not the engine causing the problem.  I'm off to start a new thread about it.