If I want to create an exclusive bloodline for one type of track. For example a race horse that has the ideal abilities/preference for 5 furlong - Dirt. How can I continue on the bloodline once I’ve created the perfect race horse for that track if the best horse is my own and its parental heritage are of all the best horses for that track. I couldn’t possibly breed it to any of its relatives as that would be inbreeding. Any advice or opinions would be appreciated.Thanks 
I’ve been reading your questions with a certain amount of interest. Breeding here works like pretty much like real life. Inbreeding and Line breeding are really the same thing in genetics. It’s done all the time in real life you just monitor how closely related the horses are. As far as creating a bloodline that breeds true to a specific surface or distance. It doesn’t happen in real life. You can breed to major tendencies so you can say the foals from a certain pairing will likely be good classic dirt runners. So you go to the breeding pages and start tracking down what your looking for. Get the best mares you can afford racers are cheaper. Check their dams foals. What bloodlines their dams bred well with etc… There is no short cut although luck is always welcomed.
Keep in mind how long breeding in this game takes. It’ll be 30-40 years (real life) before you’re anywhere close to having to worry about having the “perfect” horse. And if you somehow manage to do it, you’d presumably just continue to improve it. So you’ve got a “perfect” 5f dirt horse… so you cross it to a really good 7f horse and try to get a foal that’s “perfect” at 5-7f. But don’t worry, you won’t really be able to do it 
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Also, keep in mind real life. There are very few “perfect” horses, and even they don’t throw “perfect” foals. FF is the same…every breeding does have a chance of throwing a “perfect” horse with superawesomeamazing stats, but that chance is <= 1%. So you might end up with a nice mare who throws nice babies, but it’s not like every baby of hers is automatically going to be a 5f dirt champion.
Also, as Andrea said, keep in mind the length of time this will take. One of my mares, Playing With Fire, is arguably a very nice mare (Gold ranked and a reine-de-course mare). However, in 12 foals (10 of racing age), she has 3 (aged 3+) who have never placed in a stakes race, and 2 who never won a stakes race. Every foal is by a very nice stallion, so one could argue that all of those foals should be multi-stakes winning millionaires. Thanks to breeding luck, they’re not, so don’t expect your “perfect” bloodline to be 100% champions.
Thank you so much everyone, all this advice and information is doing wonders to improving my theories. I will probably have many more questions so keep it coming. I don’t take offence easily so if you think my questions are silly tell me.