headers on '95 351
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headers on '95 351
This is kinda long, so I apologize, but i got some real questions for an area I'm not too familiar with. I got a '95 F-150 w/ 351W vortech supercharger, E4OD. I bought the truck with all the performance upgrades. Part of what he did to the engine was put on short tube headers. I believe short tube headers are exhaust manifolds that bolt right into the existing exhaust system at the y-attachment before the cat converter. If I am mistaken, please correct me.
About two months ago, while i was towing about 4000 lbs into the high and hot places in Arizona on the way to lake mead, i developed an exhaust leak so bad that it was causing a misfire on the #3 and #4 cylinders on the passenger side of the truck. You could hear the leak clearly at idle, and it would not go away hot or cold, meaning to me the gasket was totally blown out in at least one cylinder. I made the decision not to press on with the trip, and had to figure something out in Kingman, AZ. My buddies family helped me out by loaning us a Suburban to finish the trip (I know, i was so embarassed). While I was at the lake, I had a repair shop get to work on the truck.
they called in a day or so and said the header was warped to about .03". thye recommended having it machined down to flush again, and also cutting the flange between the pipes for each cylider - meaning they made three cuts in the flange between the bolt holes and pipes for the exhaust ports. They said it should stop the leak and get me back to Tucson. The truck was not misfiring anymore either. Well, it worked great and i actually haven't touched it since that trip.
I ended up moving to Florida, driving like i was on nails fearful of the truck exhaust coming apart on me again, and breaking down in the middle of texas somewhere. And now, I am planning to tow around 4000 lbs again, this time when i move to corpus christi.
So this is where I'm going with this:
-i was under the impression that headers are like a temporary thing. they dont last as long as stock exhaust manifolds, and need to be retightened at regular intervals. true? My dad told me this, so maybe that was case in the 60s or 70s when he was really into perfermace mods on his cars.
-In anyones opinion out there, do i have another critical exhaust leak waiting to happen with my machined and cut flange header?
-What kind of options do i have for aftermarket exhaust manifolds that are RELIABLE, and dont have to be tightened periodically? If I do this, I'm looking for a little peace of mind, and a fire and forget kind of mentality - after I put them on, I dont want to have to deal with them again. options?
sorry for the long story and post, but any help is appreciated.
About two months ago, while i was towing about 4000 lbs into the high and hot places in Arizona on the way to lake mead, i developed an exhaust leak so bad that it was causing a misfire on the #3 and #4 cylinders on the passenger side of the truck. You could hear the leak clearly at idle, and it would not go away hot or cold, meaning to me the gasket was totally blown out in at least one cylinder. I made the decision not to press on with the trip, and had to figure something out in Kingman, AZ. My buddies family helped me out by loaning us a Suburban to finish the trip (I know, i was so embarassed). While I was at the lake, I had a repair shop get to work on the truck.
they called in a day or so and said the header was warped to about .03". thye recommended having it machined down to flush again, and also cutting the flange between the pipes for each cylider - meaning they made three cuts in the flange between the bolt holes and pipes for the exhaust ports. They said it should stop the leak and get me back to Tucson. The truck was not misfiring anymore either. Well, it worked great and i actually haven't touched it since that trip.
I ended up moving to Florida, driving like i was on nails fearful of the truck exhaust coming apart on me again, and breaking down in the middle of texas somewhere. And now, I am planning to tow around 4000 lbs again, this time when i move to corpus christi.
So this is where I'm going with this:
-i was under the impression that headers are like a temporary thing. they dont last as long as stock exhaust manifolds, and need to be retightened at regular intervals. true? My dad told me this, so maybe that was case in the 60s or 70s when he was really into perfermace mods on his cars.
-In anyones opinion out there, do i have another critical exhaust leak waiting to happen with my machined and cut flange header?
-What kind of options do i have for aftermarket exhaust manifolds that are RELIABLE, and dont have to be tightened periodically? If I do this, I'm looking for a little peace of mind, and a fire and forget kind of mentality - after I put them on, I dont want to have to deal with them again. options?
sorry for the long story and post, but any help is appreciated.
Elder User
Joined: Feb 2007
Posts: 829
Likes: 1
From: Goose Creek SC
You are going to hear all sorts of opinions about this. Mine is....yes.....headers do need to be re-tightened periodically. Every set I have ever had loosened and blew the gaskets IF I didn't put a wrench on them once in a while.
There are new gaskets out now and different types of header bolts/studs with locks on them that are sposed to fix that. I think I would throw a wrench on them during oil changes anyway. Doesn't cost anything or take all that long and you get a lot of peace of mind.
By the way.......Most here say the short tubes are worthless on our trucks........that the long tube is the only real way to upgrade for us. Many posts here about headers .....try a search and read opinions.
I'm your dad's age and he's definitely right about older headers. Newer are not so bad....better manufacturing and heavier flanges have helped a lot. But like I said......wrench them......you won't worry about it then.
Good Luck
Bob
Here's a nice thread about the longtubes...
https://www.ford-trucks.com/forums/6...e-goin-on.html
There are new gaskets out now and different types of header bolts/studs with locks on them that are sposed to fix that. I think I would throw a wrench on them during oil changes anyway. Doesn't cost anything or take all that long and you get a lot of peace of mind.
By the way.......Most here say the short tubes are worthless on our trucks........that the long tube is the only real way to upgrade for us. Many posts here about headers .....try a search and read opinions.
I'm your dad's age and he's definitely right about older headers. Newer are not so bad....better manufacturing and heavier flanges have helped a lot. But like I said......wrench them......you won't worry about it then.
Good Luck
Bob
Here's a nice thread about the longtubes...
https://www.ford-trucks.com/forums/6...e-goin-on.html
Last edited by 92F150Flare; Aug 17, 2007 at 11:30 AM.
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okay, with that in mind, is there a way to get factory exhuast manifolds? I'm not too worried about the performance right now, with as much as i work, and as much moving around as I will be doing, I would rather have reliabilitly over performance.
I dont want to go to a junkyard and get something from an old truck, but I was thinking like pure replacement or factory equivalent exhaust manifolds. Does anyone make them, or am I dreaming?
-did factory exhaust manifolds need to be tightened? Why not?
thanks for the help
I dont want to go to a junkyard and get something from an old truck, but I was thinking like pure replacement or factory equivalent exhaust manifolds. Does anyone make them, or am I dreaming?
-did factory exhaust manifolds need to be tightened? Why not?
thanks for the help
Elder User
Joined: Feb 2007
Posts: 829
Likes: 1
From: Goose Creek SC
LMC Truck has them
http://www.lmctruck.com/features/fd/FD.htm
You can buy replacements at Advance and other parts stores too. I'm not too sure about the quality.......probly ok from NAPA or CarQuest....and they usually have different mfgrs at different prices. If it were me I'd use LMC simply because they have them more on the OEM line.
Headers are made of steel and the the flange on them.....the part that bolts up to the block..... is very thin. The constant heating and cooling causes them to expand and contract and loosens the fasteners. It also warps as in your case. Stock manifolds are made of cast iron and dissipate the heat without the contraction and expansion......and the flanges are a lot thicker. Newer headers are made with a thicker flange just for that reason now.
Good Luck
Bob
http://www.lmctruck.com/features/fd/FD.htm
You can buy replacements at Advance and other parts stores too. I'm not too sure about the quality.......probly ok from NAPA or CarQuest....and they usually have different mfgrs at different prices. If it were me I'd use LMC simply because they have them more on the OEM line.
Headers are made of steel and the the flange on them.....the part that bolts up to the block..... is very thin. The constant heating and cooling causes them to expand and contract and loosens the fasteners. It also warps as in your case. Stock manifolds are made of cast iron and dissipate the heat without the contraction and expansion......and the flanges are a lot thicker. Newer headers are made with a thicker flange just for that reason now.
Good Luck
Bob
