I have a 99 F150 4x4 w/ the 5.4L V8. I have been looking to upgrade my stock y pipe to an aftermarket design and change the piping from the y back to the muffler to 3 inch. What size inlet on the y pipe do I need to order. I have heard that these trucks have 2 1/4" pipes, but don't know for sure. Let me know what you think?

 

Hi rabbit03

The exhaust pipes on our trucks is 2.5, you can get a Y pipe from jeg`s it`s called a Y collector part#389-Y250300A it cost 37.99.
The inlet has two 2.5 inch inlets and a single 3 inch outlet. I had 3 inch pipe added from the Y back to my 40 series flow master. I gained a noticable amount of power and gas mileage. I get 18-20 mpg now.
Hope this helps you out.

Larry

 

Hi rabbit03 and speeder,
I would recommend replacing the Y-pipe. I just had true duals installed and I looked at the stock Y-pipe after it was cut out ... a POS. Should be called the "Y-restrictor" instead!! LOL! Seriously, the stock Y-pipe is junk. If you are planning exhaust mods, definitely plan on replacing the Y-pipe. Also, Summit sells aftermarket Y-pipes too:
2.25" pri w/3" collector, p/n FLO-Y214300A
2.50" pri w/3" collector, p/n FLO-Y250300A.
The stock pipe size before the muffler is 2.50"
GDG

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Stock Package: 2001 SuperCrew XLT, Silver, 5.4L, 4x4, 3.55 LS, Tow Package, 265x70x17, Sliding Rear Window,
Modifications: Tuff Spray-on Liner, JBA Headers Jet Black Coated, True Duals with Magnaflow X-pipe 2xRavin Z55's 18"x3" Stainless Tips exiting before the rear wheel, K&N FIPK with fabricated cold-air box and ram-air, SuperChip, ASP Pullies, 1" Thick Sheepskin seat covers (nice "seat-of-the-pants" feel!), Nerf Bars, PIAA Superwhites, 65W (9006) Fog Lights, Dual 14" Perma-Cool Fans w/ stock shroud, Baumann Shift Kit on Stage 4 with Sonnex Bypass Clutch control Valve, B&M Deep Trans Pan, Pillar mounted Autometer Ultra-Lite Water and Tranny Temperature Gages, Amsoil front to back, TPS Mod to 0.999, Custom ported TB.
Future mods - Roots Supercharger, modified sterio system

 

Hi GoDogGo

Changing the factory Y was one of the best mods i have done to my truck. When the guy at the muffler shop cut it off the truck i could`nt believe what a piece of crap it was, well worth the money to have it changed. When i left the muffler shop i thought something was wrong with my truck but what i was actualy feeling was the power i had gained from the new Y pipe. By the way,
did your gas mileage go up?. Mine sure did, im getting 18-20 mpg.

Have a good day.

Larry.

 

Hi speeder,
I have not had enough miles put on yet to see if the MPG increased from the exhaust mod. I'm hoping I see a big improvement like you did. Wow, 18-20 MPG is exceptional. Fortunately, I have seen about a 2 MPG increase above stock with the mods I have to date (currently getting 17-18 MPG on highway). I would say that the pullies and electric fans had the biggest effect, but believe it or not, I think the Asoil helped a little too (Amsoil bumper to bumper). Hopefully this exhaust mod will get me in the same MPG range that you are, LOL!!!
GDG

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Stock Package: 2001 SuperCrew XLT, Silver, 5.4L, 4x4, 3.55 LS, Tow Package, 265x70x17, Sliding Rear Window,
Modifications: Tuff Spray-on Liner, JBA Headers Jet Black Coated, True Duals with Magnaflow X-pipe 2xRavin Z55's 18"x3" Stainless Tips exiting before the rear wheel, K&N FIPK with fabricated cold-air box and ram-air, SuperChip, ASP Pullies, 1" Thick Sheepskin seat covers (nice "seat-of-the-pants" feel!), Nerf Bars, PIAA Superwhites, 65W (9006) Fog Lights, Dual 14" Perma-Cool Fans w/ stock shroud, Baumann Shift Kit on Stage 4 with Sonnex Bypass Clutch control Valve, B&M Deep Trans Pan, Pillar mounted Autometer Ultra-Lite Water and Tranny Temperature Gages, Amsoil front to back, TPS Mod to 0.999, Custom ported TB.
Future mods - Roots Supercharger, modified sterio system

 

Hi GoDogGo

I guess i just got lucky with my mileage.
I went on a 235 mile trip and averaging 70 mph i got 18 mpg and i was drivin it like i stole it. so i know if i drove closer to the speed limit i could get 20 mpg. ( if im lucky ).

Larry.

 

HEY GUYS...WAS JUST WONDERING WHERE I COULD ORDERA Y PIPE AND FROM HOW MUCH.JEGS?COULD YOU GIVE ME A PHONE # OR WEBSITE.IS THE Y PIPE YOU GET FROM SUMMIT AND FROM JEGS THE SAME THING.OR WOULD ONE BE BETTER THAN THE OTHER.THANKS FOR THE INFO.OH YEAH ONE MORE THING.COULD I INSTALL IT MYSELF AND HOW HARD WOULD IT BE.OR WOULD I JUST BE BETTER OFF TAKING IT TO A MUFFLER SHOP?THANKS FOR THE INFO.

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2000 F-150 4x4 XLT
Current Mods:
Ford Window Deflectors
Ford Bug Deflectors
Continental Accesories Tool Box
Drop-in BedLiner

 

Hey Steel Breez,
Not 100% sure, but I believe most of the aftermarket Y-pipes are about all the same. Summit=1-800-230-3030, don't know the number to jeg's. Unless you have the equipment and know how to MIG weld, I would take it to an exhaust shop. Personally, I would not even think about clamping those connections.
GDG


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Stock Package: 2001 SuperCrew XLT, Silver, 5.4L, 4x4, 3.55 LS, Tow Package, 265x70x17, Sliding Rear Window,
Modifications: Tuff Spray-on Liner, JBA Headers Jet Black Coated, True Duals with Magnaflow X-pipe 2xRavin Z55's 18"x3" Stainless Tips exiting before the rear wheel, K&N FIPK with fabricated cold-air box and ram-air, SuperChip, ASP Pullies, 1" Thick Sheepskin seat covers (nice "seat-of-the-pants" feel!), Nerf Bars, PIAA Superwhites, 65W (9006) Fog Lights, Dual 14" Perma-Cool Fans w/ stock shroud, Baumann Shift Kit on Stage 4 with Sonnex Bypass Clutch control Valve, B&M Deep Trans Pan, Pillar mounted Autometer Ultra-Lite Water and Tranny Temperature Gages, Amsoil front to back, TPS Mod to 0.999, Custom ported TB.
Future mods - Roots Supercharger, modified sterio system

 

Steel Breez- It needs custom fabrication at all 3 openings; it doesn't bolt on. A superior job would require using a mandrel bent 90 degree segment added to the driver's side pipe. I took my shop one because many shops don't have mandrel presses or stock the 90 degree elbow.

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2000 F-150 XL, RC, LB, 5.4L, 4R70W, 4.10LS,
Class III tow, Payload #3, & Convenience pkgs.,
4-wheel disc/ABS, Chestnut/Parchment 40/60,
Ford bedliner w/Paintsaver & gas/wheel/spare locks,
K&N F.I.P.K. w/Outwears pre-filter, Superchip,
Dynomax ultra-flow welded 3" cat-back w/ 3" Y-pipe,
Hellwig front & rear anti-sway bars, Rancho RS 9000s,
Pirelli Scorpion Zero 275/60/16s, Mobil 1, K&N oil filter.

 

If I install the FM "Y", running 3" pipe afterward with no muffler, is this a true 3" system? At that point, the biggest "restriction" would be the CATS, manifold, and 2 1/2" pipe on each side? Would this open the system up too much?

-AR

 

Hi Jackal

All i can say is try it, if it does open the exhaust up to much you can always add a flowmaster or other muffler later

Larry.

 

The Jegs and Summit y-pipes are both the same Flowmaster units. Mine goes in this week!

 

jefferdy1

"exhaust testing every 2 years"? Are you sure that's not just a Harris County thing and pretty new? That's the first I ever heard of that.

One thing to keep in mind too, these Expy's are LEV so unless you remove the cats, you're probaby not going to have any problem.

Also, the y pipe is after the cats. Unless they've drasticly changed the 2001 and gone back to the old days. Look at your's. You see the small cats, one on each side coming off of the exhaust manifolds.



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2000 EDDIE BAUER EXPEDITION 4x2

• Estate Green
• 5.4 ltr
• 3:55 LS rear
• Superchip!
• Airaid FIPK
• Gibson S/S Swept Side Cat Back Exhaust
• Hellwig Rear Anti-Sway Bar
• Energy Suspension Polyurethane Front Anti-Sway Bar Bushings
• Edelbrock Performer IAS Shocks
• Mobil 1
• Xenon Super White Head and Driving Lights
• Tow Package
• Rear Load Leveling
• Moonroof
• Century Child Seat!

-->Follow Me...<--

 

FamilyRide,

It is a Harris County thing with the exhaust testing every 2 years. I kinda thought the guy didn't know what he was talking about since I asked him if it had dual cats. If the Y-pipe was in front of the CATS then wouldn't it only have one CAT? Just wanted to see who other people in Houston/Katy were using for exhaust upgrades.

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jefferdy1

 

Hey GoDogGo where in Houston did you go for your Y-pipe install. I went to a Mike's muffler out in Katy and they said they can't change anything before the CATS. I have 2001 Expy and I want to do the Y-Pipe and muffler swap out (probably go with a Dynomax). The only way they could do any thing before the CATs was to go with a true Dual. If anyone knows otherwise let me know. Keep in mind I live in Texas and we do have exhaust testing every 2 years.

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jefferdy1