mrb5_supra_wrx

hey guys new to the older audi scene but been an audi fanatic for several years. Ive owned several b5 and b6 chassis audi's along with a few s4's and just wana give a hello to the crew first off. But i will be picking up an 89 200 10v quattro here shortly a guy has one local and im picking it up. Seeing ive always loved these cars but never been able to find one. Well only thing thats come to play as of yet that im having issues with is... finding adequate enough info on these engines. Of course i would love to find a 20v 3b, 7a, or aan engine car but where i live im lucky i even found this. So really trying to research this engines has kinda been a pain not seeing much about them. Theres more info on the 20v than anything so what i want to find or if some of you can help me with is. Im Looking to put some power to the engine but i want to do it safely and right. But i cant find any info about like what are the 10v capable of making with the stock internals? ive read about a chip, wastegate spring and a few other things but how much power can i safely make without blowing the engine? And not really seeing anything anymore about tuning these engine, or building blocks at places like 034 and a few others that apparently use to have this info or parts. I would like to build a decent 300-400 whp car if its capable without building the block. And of course after a good build shoot for more I know if it was a 20v wouldnt be an issue whatsoever but wanting to know my options with the 10v. Or hells would it just be worth it to find a 20v long block harness and ecu and swap it? what are my options guys?? And thanks in advance