Got a 85 4x4 stanard 4 speed pickup with the 4bt. The motor starts the first roll over and does good. The motor in the pickup was the 6.2 (that made it to 250K) so the change over wasnt all that bad. You will have all kinds of room to work with. The motor has maybe more power slow than the 6.2, just wont rive up very fast(top speed is 68mph with the 373). The motor I have is total stock, with power to do what I do. The fuel milage is always over 20 mpg so I am not going to change anything. I am not telling you what to do, just telling you how it is working for me. Good luck.