Too much backfire

I was playing with a custom tuned D series (not my mod) and I feel like there's too many backfires going on. I don't think a 5.5L V8 engine from the 80's can backfire that much same goes to all other vehicles. I don't think that a truck/car can backfire that much IRL

 

Year of engine matters not. But technically a newer engine will actually manage less than the oldies.
You'd be surprised by reality. I don't know of any car capable of a 100% complete burn of fuel combined with an exhaust that does not get hot.
It really depends on the exhaust and tuning of the engine how much it may be audible and visual.
Custom tuned D-Series = Supercharger = More heat, more fuel, more timing = Afterfire

 

You can change the backfire pretty easily in a file

 

Change these two variables in the muffler/exhaust jbeam to be what you want