A standard 90 degree V-8 has a burble due to irregular firing intervals. But with a cylinder down, it sounds very different.
A well designed twin pipe system will have a balance pipe between them. To even out the extraction effect. But even without, all you've done is half the choices.
A decent rev counter will show which cylinder is poor by unplugging each plug in turn, and noting the engine speed. But you should be able to hear this anyway.
Yaris packs seem to be very popular for conversions. £100 for 8 (or thereabouts). Of course you?re gonna need other sensors and engine management systems as well.
Tim
Funny, those were my precise thoughts too. An eye on the rev counter should be sufficient to see the change.
I have known someone have a faulty ignition lead on his Rover V8 and not know about it for months. He was an artist whose job was to airbrush celebrity photos.
Those plug-top coils don't have a very long service life, though. They tend to fail far more frequently than the single, distantly-placed coils. The cost of that could really add up.
Or no gloves at all. Then if you cop a belt you'll know the insulation's duff on that lead/cap.
With older pushrod engines (like my Rover V8) you can't really use Coil on Plug because of the heat from the exhaust manifold. But there are individual smart coils where you use a short plug lead to them, so can be situated anywhere convenient.
But I'm using wasted spark. One coil per pair of cylinders, and only needs a crank trigger. Ford EDIS was an early type and still works well as it is virtually bomb proof. It is pretty well maintenance free. But does need an ECU to control the advance curve.
Yup. They don't tend to run rough like a four cylinder does when you lose a cylinder. Just down on power.
I'm wondering if the leads being in trunking makes them very difficult to do a visual check on. Making them all the more likely to be the source of the problem, if difficult to change. ;-)
Asking for trouble on multiple levels. A better idea if neatness was a consideration was to use those rubber spreaders, then it's simple to inspect the leads and remove them for easier testing if suspect.
I can remember cars of a certain age having carbon(??) core HT suppression leads and after a few years caused all sorts of starting problems in damp or cold weather. The starting problems were cured with a simple change to new copper core leads.
IIRC, carbon impregnated HT leads were introduced because they were better at suppressing radio interference than resistive plug connectors (or using individual series resistors).
Having a high-resistance (or even open-circuit) HT lead can have knock-on effects. I recall that in one of my cars the shortest lead went almost O/C, with the subsequent misfiring problems. As the coil could not deliver a spark across the plug gap, the spark chose instead to track between the coil HT terminal and the 'LT' spade terminal. This carbonised the insulating material, and I still had tracking problems after I had replaced the faulty lead. As a 'temporary' fix (until I got a new coil) I sawed a chunk out of the insulation, and filled it with. The fix became permanent, and I never used the new coil.
Replacing carbon string leads with copper is an absolute no-no. The ignition system is designed to work with a total resistance between coil and plug of about 30,000 ohms. And that's before you blot out surrounding TV etc reception with the interference it would generate. And on a modern car, that interference can also zap the engine management.
Suppressor leads using conductive plastic rather than carbon string have been around for many a year now, and have a very long life.
I am assuming that theres a capacitor inside the distributor, and that its been checked, although I can find no mention of it anywhere in this thread.
AT
I presume that no-one has fiddled with the ignition wiring recently? About 30 years I had a car which was factory fitted with a 9v coil, fed through a ballast resistor. When the starter motor was operated, the resistor was by-passed to give the ignition a bit more oomph.
I had some work done by a garage who reconnected the wires in such a way that the resistor was always out of circuit. With the full 12+ volts going to the coil all the time, the engine misfired profusely - and wrote off the coil *and* the points in short order.
That couldn't be the OP's problem could it?
In my youth you sometimes found 6 volt coils with a ballast. But there were (just about) 6 volt cars still around in those days, and I never owned a 12 volt motorcycle.
Fords used this technique. The spark was marginal when cold and a consequence was that the engine died as soon as you let go of the starter.
The OP seems to have abandoned this thread so we'll never know.
Think most recent ones are 9v. On the principle that if the battery volts dropped below 9, it is probably too clapped to turn the starter.
It's more that the internal resistance of the battery when the starter is pulling a few hundered amps from the coil to around 9V. V8 landrovers had such a dropper but I though 6V coils.
Bit wasteful having to drop the voltage more than needed using a power resistor?
It could be early cold start systems use a 6v coil because they were a standard item. But once common makes sense to use one designed for the job.
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