4" Exhaust
Thread Starter
|
Freshman User
Joined: Feb 2004
Posts: 40
Likes: 0
From: Romeo
4" Exhaust
I have a 99 PS (2/99) with 125K on it. I'm running a 60HP chip and original airbox. I want to go with the 4" exhaust but have some questions. Does anyone have comments on how difficult it will be to remove to stock downpipe? Does anyone know if it is a 3.5"?
Postmaster
Joined: Feb 2002
Posts: 2,773
Likes: 0
From: Bonney Lake, WA
On your truck, I'm not sure if your stock downpipe is a 3.5" or only a 3". On my older style truck, it was a flattened 3", but didn't flow like one. Removing the old downpipe is the hardest part of the job. It took some 6" blades on the Sawzall, and since the downpipe is stainless, it'll probably take more than one.
Thread Starter
|
Freshman User
Joined: Feb 2004
Posts: 40
Likes: 0
From: Romeo
I was worried about rusted bolts. Is that what the sawzall is for or do I need to cut the pipe off? I've read here that I may be able to connect the 4" exhaust to a 3.5" downpipe. That sounds like a better option.
Postmaster
Joined: Feb 2002
Posts: 2,773
Likes: 0
From: Bonney Lake, WA
I haven't spent nearly as much time under the hood of a SuperDuty as I have an older truck like mine. My original downpipe was smashed flat by Ford, trying to get it to clear the firewall. If yours is also flat, replacing it with either a 3.5" or 4" would do you a lot of good. If yours is actually round, it's likely 3", and you'd need the Sawzall to cut through the old one, to get it off.
You disconnect the downpipe from the turbo by loosening the Marmon clamp that connects the two. A 7/16" deep socket will do the trick. I assume you're going to be replacing the entire exhaust system while you're at it, so just cut it up in manageable sized chunks.
I hope this helps.
You disconnect the downpipe from the turbo by loosening the Marmon clamp that connects the two. A 7/16" deep socket will do the trick. I assume you're going to be replacing the entire exhaust system while you're at it, so just cut it up in manageable sized chunks.
I hope this helps.
FTE Leadership Emeritus
Joined: May 2001
Posts: 13,653
Likes: 6
From: Cabot, Arkansas
micguyver
Your stock downpipe is a 3" round (non flattened) pipe. The rest of the stock exhaust is 3.5", all stainless.
You could get away with just upgrading the downpipe to a 3.5" piece if you were so inclined, and if you do upgrade the entire system I would recommend sticking with a 3.5" downpipe as you will keep a little better throttle response with a 60 horse tune.
Only two cuts are neccessary to remove the stock exhaust. The first is on the downpipe just in front of the tranny crossmember. The second is behind the muffler far enough back to get the tailpipe out over the axle.
I used a 4" angle grinder with a 1/8" cutting disk. Took about 10 minutes total to get the old exhaust out.
Your stock downpipe is a 3" round (non flattened) pipe. The rest of the stock exhaust is 3.5", all stainless.
You could get away with just upgrading the downpipe to a 3.5" piece if you were so inclined, and if you do upgrade the entire system I would recommend sticking with a 3.5" downpipe as you will keep a little better throttle response with a 60 horse tune.
Only two cuts are neccessary to remove the stock exhaust. The first is on the downpipe just in front of the tranny crossmember. The second is behind the muffler far enough back to get the tailpipe out over the axle.
I used a 4" angle grinder with a 1/8" cutting disk. Took about 10 minutes total to get the old exhaust out.
Posting Guru
Joined: Oct 2003
Posts: 1,332
Likes: 4
From: Baltimore
Is it necessary to cut the original downpipe or can it be removed in one piece? I have a Banks downpipe coming and prefer not to damage the original pipe if I don't have to.
Trending Topics
Thread Starter
|
Freshman User
Joined: Feb 2004
Posts: 40
Likes: 0
From: Romeo
Cookie88, thanks for the advice. This is the first truck I've owned that I have no intentions of getting rid of. I have decided to replace the entire exhaust with the 4" stainless and stick with a 3.5" DP. I have no problem spending the money for something that will last. I am still struggling with the intake though. I live in dusty conditions and have a hard time changing to the "open" type of filter system such as the Tymar. Probably will go with the AIS, assuming that the replacement filter cost will drop over time.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Posting Guru
Joined: Feb 2004
Posts: 1,873
Likes: 1
From: Phx, AZ
air cleaner
Micguyver
Hey good call replacing the entire exhaust. Your kit will come with a 3.5 in dp and a 4 in mandrel bent piping along with a straight pipe muffler. This will make a huge difference in letting your psd breathe. For you air cleaner look to the air raid intake and a K&N filter and do not over look the pre cleaner. It is an extra sleeve that goes over the K&N filter that makes cleaning so easy and keeps the bugs off the filter too. I live in phx Az and believe me you would be hard pressed to find many places dustier then here ( well other then San Angelo Tx). Good Luck!
Fire Rooster
Hey good call replacing the entire exhaust. Your kit will come with a 3.5 in dp and a 4 in mandrel bent piping along with a straight pipe muffler. This will make a huge difference in letting your psd breathe. For you air cleaner look to the air raid intake and a K&N filter and do not over look the pre cleaner. It is an extra sleeve that goes over the K&N filter that makes cleaning so easy and keeps the bugs off the filter too. I live in phx Az and believe me you would be hard pressed to find many places dustier then here ( well other then San Angelo Tx). Good Luck!
Fire Rooster
Senior User
Joined: Feb 2004
Posts: 227
Likes: 0
I went with AIS due in some consideration of warranty issues. As far as K&N, most people on here curse them, according to everyone they don't seal well. Filter cost may go down on AIS but I doubt it, at least if you get the Donaldson, and not a knock off, filter made for it.
FTE Leadership Emeritus
Joined: May 2001
Posts: 13,653
Likes: 6
From: Cabot, Arkansas
slc10844
You don't have to cut the stock downpipe, but in order to remove it from the truck un-cut you will have to get out the floor jack and remove the transmission crossmember.
micguyver
Being a performance oriented type of guy I'm not a huge fan of the AIS. It is probably the best filtering intake on the market, but the maximum flow rates suffer as a result. Replacement filters are also around $70 a pop. Whereas the Tymar type setups will support any current of future mods, and only lose a couple of thenths of a point in the filtering ability. Replacement filters run $19-$30 each depending on where you get them.
The only real downside of the Tymar is the warranty issue. As soon as a Ford tech pops the hood the jig is up.
You don't have to cut the stock downpipe, but in order to remove it from the truck un-cut you will have to get out the floor jack and remove the transmission crossmember.
micguyver
Being a performance oriented type of guy I'm not a huge fan of the AIS. It is probably the best filtering intake on the market, but the maximum flow rates suffer as a result. Replacement filters are also around $70 a pop. Whereas the Tymar type setups will support any current of future mods, and only lose a couple of thenths of a point in the filtering ability. Replacement filters run $19-$30 each depending on where you get them.
The only real downside of the Tymar is the warranty issue. As soon as a Ford tech pops the hood the jig is up.
Last edited by cookie88; Mar 18, 2004 at 09:17 PM.
FTE Leadership Emeritus
Joined: May 2001
Posts: 13,653
Likes: 6
From: Cabot, Arkansas
Not really. The Tymar filter is an 8"x10" round filter, that is an enormous amount of surface area. The AIS filter has a similar (or slightly higher, can't remember now) surface area, but it is stacked.
What I mean is with the big Baldwin filter that comes with the Tymar the entire surface area of the filter is open for the engine to draw through. With the AIS the air must be pulled through layer after layer of material in order to utilize the entire surface area.
Both filters hold a similar volume, but the Tymar breathes easier doing it. Both of the filters are supposedly able to hold enough dirt that they only require annual changes.
What I mean is with the big Baldwin filter that comes with the Tymar the entire surface area of the filter is open for the engine to draw through. With the AIS the air must be pulled through layer after layer of material in order to utilize the entire surface area.
Both filters hold a similar volume, but the Tymar breathes easier doing it. Both of the filters are supposedly able to hold enough dirt that they only require annual changes.