I have a 1984 F150, 302, stock except for the new Edelbrock carb and intake I put on after the 2 barrel went caput. This engine was making a lot of HP at he low end before I made change, but ran good. Now in the upper rpm's it does not get sluggish but I am getting, well it sounds like back fire. So I figured now that I have opened up the air flow, I am making more HP in the upper rmp range and the timing was not advancing enough to keep up. When I advance the timing, it gets rid of the back fire, but I loose some low end HP and get pinging. Got a full rebuild in mind to make good use of the new 4 barrel, but until then any suggestions?

 

Do a "sixlitre tuneup".

http://fullsizebronco.com/forum/23-t...mp-no-56k.html

 

When I saw your post, I was thinking, what is that! Take the 302 out and put in a 400. But after that I looked at the link and I will give that a shot. More fire may be answer to my issue. Had not thought about that since I had not replaced cam or anything like that, but it makes sense now.

 

O and thanks for the info. You would not happen to know how new of a seat I could put in this 84 do you? I do not know what year they changed the floor pan or if they even have. Would like to upgrade seat from bench seat to one of the newer 60/40 splits without having to do too much work!

 

After you are done, if it pings, you have to either retard the timing or use higher octane gas.

Can't help you on the seats, sorry. A junkyard cross reference book may help.

 

I suggest you check the compression just to rule out a burned or leaky valve. Then, I'd consider replacing the timing chain. It may be very slack.