I have an old gas oven at home which is generally pretty rubbish at most things.  The temperature in the oven is wildly off compared to what the dial says it should be; there are hot/cold spots throughout; the top temperature is adequate for most of my needs, but on occasion I've wanted a really hot oven and it's never been able to get there.  Is there anything I can do to make my oven better? How can I hack it?   I've just bought a probe to use with my digital thermometer and the oven, but I was wondering if anyone could recommend anything else?  I've considered the following options, but unsure if they are good ideas or not:   Putting a fan in the over to help circulate the air around. Getting a pizza stone to put in the bottom of the over to keep heat when opening the door   ** edit **  I would replace the thing but my kitchen is really small so I'm stuck with having to buy a very narrow oven which severely reduces the selection I can choose from. 
I think you may reach the point of diminishing returns if you try and fix your oven because there's lots that could be going wrong. It could be that your oven design is just bad, in which case you can't fix it anyway. It could be a faulty temperature sensor, or a bad gas valve, or a faulty burner. Your gas supply pressure could be inconsistent. By the time you replace all these you'll have spent more than a new oven would cost.   I'd first clean it really well. Get all the dust and gunk out and see if that helps. Then you should see if you can find a pro who can have a look at it, test the gas supply, see if there's any quick wins.   One suggestion I'd make would be to post this on the diy stack exchange forum, the home improvement site. As this is more a question about mechanics and repair you're likely to get a better answer there.  