Microlighters

Hi everyone
Sorry for this stupid question.
What does a Rotax 582 engine with blue / green / gold or what colour top mean?
Is this the replacement of the cylinder head with a reworked top to get more power or what?
I would like to get more horsepower from my standard 582 as it is a no nonsense engine that use more fuel,
but how much fuel do i need to put in extra to make up the R 100 000-00 plus everyone ask for a second hand 912 engine.
My engine has less than 100 hours and i need some advice to upgrade the horsepower.
Perhaps a coloured top and reworked exhaust system as long as i dont have to spend the kind of money for a new engine.
Any suggestions , adresses , telephone numbers and e mail adresses will be appreciated
Anyone visiting Swakopmund in Namibia please contact me if i can help with any info , accommodatiion etc
regards
Johan de Wet
00264 81 124 8283
jdewet@mweb.com.na

Johan......there are only two types 582's. A silvertop (mod 90) and a bluetop (mod 99). They are essentially the same except that the blue top has some additional plumbing that recirculates the water around the cylinder head to maintain heat in the cylinders and the conrods in the crankshaft are 1mm wider and the conrod big ends are 2mm bigger. The power output is exactly the same.
It is futile to try and beef up a 582 for more horsepower. The exhaust system is already optimised for maximum performance. If you try and put a tuned pipe on it you're only looking for trouble and you'll soon be spending the kind of money that you're trying not to spend. I'm not even going to try and explain that as this topic has been covered before at length (do a search for it).
The best you can do is try and find an older, used Rotax 618 (75 Hp I think) but they are scarce and Rotax does not support them any more. There's no such thing as a reworked head on the 2 strokes as they are exactly that, 2 strokes. Nothing in the head can be reworked like a 4 stroke.
Sorry to be the bearer of bad news...............

Thanks Duck
So this is actualy small changes in the cylinder head plumbing and bit stronger / better bearings.
This is no bad news and it looks to me that an advert of a blue top does not differ much
from the stock standard 582.
Power wise where i fly 99% of the time at sea level is ample and i will keep it simple as is.
Appreciate your answer
Johan