help!!!!please!! weird noise

[crismonaco]

hey people new to this site hoping someone can help me im 23 and have a 1972 charger never been in snow or rain and has been stored in a garage since 72 comes out a few times every summer only has 50,000 miles on it ive been putting in alot of money and now i have a new problem im here in canada speed limits 100km/h on the highway i was doing about 120/130 a couple days ago no problems but i noticed everytime the car hits 80 right on i hear like a popping noise only slowing down never acceling to 80 or more and always at 80 never any other time if anybody has an idea please email just mark subject of email as charger help cris_monaco@hotmail.com thanks!

[TylerCharger69]

Well....decent punctuation would help us understand exactly what your symptoms are.

[c00nhunterjoe]

sounds liek you are describing it detonating on decel, a simple carb/timing tune will fix the problem if it is what i am thinking you are describing 

[b5blue]

Need more detail like from front or back, thud or ping ect.