Idle Speeds/Fuel Economy

[demos]

My current project (i know, i need to post some pictures already...i'll get to that soon) involved me incoroporating a 350W Power inverter into my 94 S-10 ext cab.
I did install a circuit that will break the inverter off if the battery gets too low.



now, here's the problem. i will be using this for long consecutive periods of time, while parked. Its part of a camping/tailgating package i'm working on. In order to keep it running, i have to keep the truck idling a lot (about 30min of every hour).
So, is there an easy modification that i can do to drop the idle speed down some/save some gas while i'm idling for this purpose.

sorry i can't make it very clear what i'm trying to do...just trying to do something to save some money on gas

[rockman20]

I think I would of bought a small generator. I'm sure that it is easier on gas, you can use more objects on it, it's portable and could be used for other things then just camping/tailgaiting, and it is a lot easier on your truck. Engines build up carbon when they just idle all the time. Excess carbon build up = poor engine performance. Poor performance = more gas.

I would of stuck with a generator. Fits in the bed, can be moved out of site if too loud and run extension cords to it. A little spendy, but price will be offset with the cost of maintenace on your rig, the amount of gas used to run it, the price of the inverter, the price of the low voltage circuit, etc.

You could try to idle it down some........but I doubt that it will run right then. And you may idle too low where your alternator isn't able to put out enough to keep up.

[piecesparts]

The issue with idling a motor is just that you idle the motor and build carbon on your valves and pistons. This will leave you with places for "HOT SPOTS" at a later date. The Power plant that I work at has two 14 cylinder diesel generators for "Emergency Power". If at any time they idle or run a low speeds for 30 minutes, the recommendation from the manufacturerer is to run them fully loaded for an hour to clean them out. (Same Principal)

Idling the motor down to a slower RPM is a bad idea for the alternator, also. The design of most alternator/regulators is that they carry around 35 amps at idle/low RPMs. When the alternator is reved over 1000 to 1500 RPM, then the voltage regulator picks up the diodes and carries more amperage. There are alternaotrs that will carry 85 amps at idle, but they are somewhat pricey. If you idle the motor down more, then you are not even carrying the 35 amps and the R-squared losses (heat buildup) in the alternator will slowly deteriorate it. Most organizations, like the railroads, and field construction crews, go through alternators quite often in their equipment.