2.3 SOHC swap for DOHC

[Maverick30 6]

i just recently needed a new moter for my 93 2.3 sohc i found a 92 dohc and put that in and it runs. the problem is that is running rich and when you accelerate it bogs down and stumbles all over itself but sometimes it takes off like a rocket it almost felt like the coils were bad but that wasnt it. i gave it the usual tune but its still give me trouble if anyone can help let me know thanks