what type of engine upgrades are available for 1995 Thunderbird
That all depends on what is in it now, V6 or a V8. Check out Crate engines, you can buy a variety of mods already done, but be careful about getting too wild as the stock computer system can't handle anything wild.
That T-Bird came with either a 3.8 V6 or a 4.6 SOHC V8. Both are common and easy to find. Mods that drastically increase power would be some sort of forced induction i.e., super charger and / or turbo charger. Both these options are very expensive. Other mods such as headers, cold air intake and exhaust yield small gains. If you are into modding perhaps consider a different car.
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