To add to my earlier advice, which Ricmondo's just reiterated, I did the sorts of things you are looking to do now to my first car i.e. make it perfect and beautiful. In my case I started with a basket case of a car (an old BMW 2002 tii which had been badly patched up for sale but I hadn't realised it) when I bought it - much as you didn't realise the car wasn't what you were expecting in terms of power. Being young and pig-headed I spent over £3000 on a car I brought for £700 and ended up scrapping it.Ricmondo wrote:That makes a lot of sense, it's good to stand out in a crowd and it makes it easier for the bloke you accidentally cut up yesterday to recognize your car in order to key it, the police will love you too as they will be able to pick you out easily and reward you with a nice ticket.
You can squeeze a fair bit of extra power out of a naturally aspirated engine with a proper remap. It will be expensive and there will be compromises typically engine life, economy, drivability, hot starting, altitude or temperature sensitivity etc, your insurance company will probably screw you too unless you have many many years ncb or are about to draw your pension.
The advice you have been given about trading up is sound.
It was a great lesson to learn as no-one died, and I've since realised that the car companies have spent loads of money refining and making my car work well - so it's unlikely that I'll find that extra bit they didn't realise was there, unless it is about modding it to increase power at the expense of probably safety and reliability. This is even more true of older cars - they tend not to be up to factory spec in many areas that are quite important - like brakes. So, for older cars, the best VfM is always to buy the car you want in the first place, look after it and make some cosmetic mods if you want to make it look unique, but don't waste your money on trying to make it quicker unless you are seriously into the car modification scene and know a really good mechanic who'll help you out at non-garage prices...