another backfireing V8

[anaxemurderer]

Have some problems with my rrc, its got a 3.5 on twin su's and was rebuilt approximately 2500 miles ago.

Has been running well but is now suffering from loss of power. Backfires quite alot, on gear changes and at high revs. Has been developing for a little while, was always worse on the way home (i guess cause its thoroughly warm and no longer in low box).

We were pretty much thinking ignition timing? Which we will get checked out properly.

Noticed today that the earth strap to the coil was very loose. What could this have done to the coil (i've fixed it now).

Any advice welcome!

Nick

ps seasons greetings!

[ben_haynes]

It could be Ignition timing but could also be a bent or twisted Distributor, a friend had one that had similar Faults

[Range Rover Blues]

Worse when it's warm, hmmm.

Could be fuel mixture but I'd start with the plugs, get them out and look at them, they could be overheating (lean mix).

The earth lead to the coil, you don't mean the one that goes to the dizzy do you? coils are switched on the negative side, the positive is always connected when the ignition is on.  If you mean that wire then there you go, the ignition is being distrupted and the engine moving around as you come off the gas could be enough.

If you mean earth strap to the engine then it's still worth fixing, I have 3 on Blue  they are important.

[anaxemurderer]

Will take plugs out tomorrow, have a sneaky peak. Always seems to have been running a bit rich, its due some tlc so proper carb adjustment might be in order.

No i mean the earth strap to the engine (which goes through a little black box - ballast resistor?). I have fixed it anyhow. Don't understand what it does, its on the same terminal as power in from battery/alternator?

Nick

[Range Rover Blues]

Sounds like a supressor, does your radio whine more than it used to?

[anaxemurderer]

Mechanic guy i was talking to thought it could be the carbs freezing up. It doesn't have a pipe from exhaust manifold to help warm the intake air.