Quote:
Originally Posted by Rosieuk
But I've a question. As I understand it, from whats been said on here - the closer you are in total engine power to the speed window that you use (in my case 0-75mph, 30-60mph predominantly) the more efficient.
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Not exactly. But the closer you are to producing your peak torque at some road speed, the better. For example, if you have a top gear that can barely accelerate while doing your chosen speed, it's going to be about as efficient as it gets. That's why my 4.0L 1500kg sedan can get 6.5 l/100km, it does about 1800rpm in top gear at 100km/h.
Quote:
Originally Posted by Rosieuk
My car, flat out will do 108mph on 86hp in top apparently (you'd have to be Stirling Moss, or tired of life), and 70mph is 3150rpm. It's a 12v and therefore feak and weeble until it comes on torque, which starts to happen just above 2200.
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Quote:
Originally Posted by Rosieuk
If I disable a cylinder that gives me a 64.5hp triple and 70mph is almost 4000rpm, outside of the max torque window - but would it be overall more or less efficient, all other things being equal?
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Not how it works. If you disable a cylinder it's still there being a drag, costing energy and providing nothing, and the gearing doesn't change because of it. Less efficient overall. UNLESS you physically stop the valves from opening (still friction, but much less pumping losses). Then it's almost worth it, but only at low loads, and your engine runs rough. Still no gearing change, but the remainder of the engine runs at a higher load and produces better BSFC (fuel consumption per horsepower generated)
Quote:
Originally Posted by Rosieuk
Also how would I go about it, this is a hydraulic lifter engine - I can pull the injector cable and remove the spark plug but won't that barf oil everywhere unless there's some sort of 2 way valve plug replacement? I seem to remember it'll send the oxygen sensors up the pictures as well..
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If you really want to try it, remove the lifters and/or rockers for the desired cylinder if it has one, and disconnect the injector (replacing it electrically with a resistor). Check the cam doesn't hit anything once moving parts are removed, and monitor your oil pressure. It *might* work. On some engine designs the cam lobe could hit the top of the valve though, and then you're up for most of a new engine.
Quote:
Originally Posted by Rosieuk
would I be better off finding out whether the 0.719 top gear from the i10 would fit to replace the 0.825 I've got now? that's a 12.5% ratio change. But expensive if possible.
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Do this first. In fact there are multiple other things to do first, but this is the only feasible thing you have mentioned that may help