Hello all,

Just installed some used Hooker comp headers on my truck (69 F100 w/360) then drove the truck to the muffler shop. Since I've got a camper special I had to route the mufflers outside the frame rails. On the way home the truck ran like crap. It was backfiring and popping all the way home. Just wondering if I need to adjust my carb since I installed headers. Any other help would be greatly appreciated.

Thanks for your time.

 

the only thing I can think of is that maybe the headers are leaking which I heard can cause a backfire. Or maybe you got some of the plug wires mixed up (always a simple problem) Good luck bud

 

Hmm that sounds like your running an older MSD A6 ign box. These were known for getting cook if power hot wire was not removed from battery while doing any welding on the vehicle.. Other then that your engine could be running now on the lean side. But should not pop & backfire. More like no power. orich

 

Sounds like your timing is off. I would recheck the timing, check plug wires, make sure plug wires are routed correctly. Check for exhaust leaks. One thing with headers, when tightening them, torque run engine at normal operating range let cool, torque again. Do this at least three times after the third time of torqing you should be sealed.
Check everything related to timing.

 

Thanks for the tips. I'm going to give it another look today.

 

So you only installed headers and did not change nothing else on the engine? How far did you drive the truck with just headers on? How does it run at idle? smooth or sound like its missing?

I KNOW its an "old wives" tale, but be careful when driving a car with open headers. Running open headers can burn your exhaust valves, but I dont think thats the case here.......hopefully!

 

If I remember right it was unless then 18" was the shortest. Odd running until welding pipes on.No computer to damage. But truck may had ran bad to the shop and didn't notice, due to the great sounds of the drag race trucks. I'd think the spark plugs wires may had got damaged some way while installing the headers, As it's not an ez job unless your putting on shorty headers that go on with no jacking up the motor or anything like the longer tubes.Shorty's Just put place with RTV and bolt them up. EZ..
orich

 

Hey all,
Thanks for the help. After a day off from looking at everything but the plug wires I decided to start from the simplest problem and work my way out. I'll bet it helps to have the plug wires on the right spark plugs. I was in such a hurry to get everything back together I accidentally swapped two plug wires. Please be merciful with your responses.

Make that a lesson to take your time when putting your motor back together.

 

Yea like no else on here has done some thing like that. Been there done that, glad to hear an easy fix!

 

At least its fixed!

 

I know this might sound silly, but could you upload a picture of your spark plugs wires order and your distributor position?
See, the thing is that I have the same problem as you did. I have a 69 F-250 camper special and I have already changed the spark plugs but misplaced the spark plugs wires and now the truck doesn´t stop backfiring and popping tru the carb.
I have use this photo to have an idea where to put the wires but this haven´t resolve the problem yet. (can´t post attachments yet)

Need your expertise on this.
Thank You!

 

You just need to learn to do a search on the net. [URL=http://good-times.webshots.com/photo/2067127430097462467cuRIPd

 

You just need to learn to do a search on the net. click on the link below
http://inlinethumb04.webshots.com/42...500x500Q85.jpg

 

Orich thank you. I know how to search on the net. Believe me. I also have this photo and tried to post it as attachment but unsuccesfully. Maybe because i´m new to the forum.

The sparks plugs were replace for new Autolite 45´s and correctly gapped. The wires were attached as in the picture, but the truck keeps backfiring even at low RPMs.
Could it be a bad fuel pump? Do i need to replace all sp wires?
Thanks in advance for your comments.

 

I bought my '67 F100/352 with a bad miss/pop situation. I finally pinpointed it being two plug wires swapped on the cap. Wow...sure did run ALOT smoother after that. Doh!

Backfiring could also be a valve issue. Depending on where it's backfiring(carb or exhaust) is if it's intake or exhaust valve hanging up.

How good are plug wires? If they are marginal, dry/hard replace them.