Backfire Shifting into 5th..thoughts???
 

Recently, during some high speed blasts on the freeway, I noticed that when shifting into 5th after topping out in 4th, i can hear a small backfire once i get engaged in 5th (not powershifted).

Does the computer retard timing at the 4-5 shift?? I thought the 94-95's did, but mine is a 93 LX.

Is this normal??? It happens everytime I shift into 5th at 5500 rpm.

Car runs fine, little smoke under hard acceleration, but idles perfectly and runs great. 88,000 original miles. 5spd, ram air, pulleys, 373s, offroad exhaust----basically stock.

My guess is the car is running lean. 5th gear is the hardest on the engine, under a load and running lean would make the car pop.