backfiring

[HoodStrype]

I think we need more info...

1) Have you done any mods recently
2) Have you messed with the vacuum lines
3) When was your last tune up

If you don't have a timing light, or the means to rent/borrow/buy one, I'd suggest taking that car to a shop. Vacuum issues, fuel issues, distributor issues, timing issues? I'm recanting what I said cause I think it could be a number of things.

You need a Haynes or a Chilton's Manual for that car. It has a trouble shooting section. I'd start with a tune up and timing check personally just so I could eliminate simple things.