i was wondering what to do or where to go to get a 3 in pipe out of the manifold.... im looking for a 3 in from manifold to stack i can build it from where the y pipe comes together from the manifold but was wondering how all that goes together up there and if there was a way to get that 3 in from the manifold all the way back

 

Check my reply in the other thread on custom 3.5 exhaust. Essentially you can do whatever you want, just depends on what tools/material you have at hand. You can go to a JY for pipe or a auto parts store. Most of them will carry walker exhaust and believe me they make everything. I have most of the part numbers from what i used but describing how i did it is a pain. It was many hours of busted knuckles and frustration but when it comes together, it is like magic lol. Just check out my album of pics. I am loading more as we speak. You can check out my custom stack that my dad made for me too, friggin cant wait. It will be here this week!!!! Do you have a welder?

 

yea i have access to a stick and mig welder. does walker make a 3 inch out of the manifold that will bolt straight up?

 

The design of the clamps on the manifold will not let you start there with 3" pipe.

2.5" OD pipe is about as big as you can get in the clamps, and that may take a little work with a grinder to get it in there.

If you start with 2.5" pipe for each down tube.

If you look at the stock Y pipe it is really more like a T where the down pipes come together.
Not very good flow from the drivers side manifold on the stock pipe.
More angle to the rear helps the flow considerably.

And when both pipes come together, the pipe should be a 3" that they dump into, not the 2.25" ID pipe Ford used.

 

is it really going to make a difference for that section from the manifold back to the y or t if i change it all over to 3 or 3.5 or am i just wasting time and money?

 

In power and in mpg. It is truly a choked down version in its stock form. I am not sure why they did that to them....the idi n/a's and the early turbos.

On a side note, early stock idi turbos and strokes play catch up till about 45mph. So it definitely did something! hahaha

 

does anyone have stats on the bends coming out of the manifold down to the y or t like how long and what degree they are? im 70 miles from my truck during the week or i would go look myself

 

In short no. But i figured two more inches of 2.25 pipe wasnt going to make it any worse or better. So i fabbed a 2.5od to 3id expander right there where it meets the manifold. Worked great. It fits loosely over the 2.25 but with the welder and a mallet, anything will look great in the end.

So what i did was cut the flanged pipe off at about three inches in length. Put the sliding exhaust flange clamp thing(what is it called? lol) in place and put the expander over the short piece of pipe. Welded it in place. Ground it down to pretty much smooth and bolted it into place. Then i got the piece of fabricators pipe, the 3" by 8ft one with all the mandrel bends and estimated which piece would be the best down tube from the manifold. Where the old pipe ran was right under the bellhousing drip hole so i modified the angles and location to go more to the rear and not at a 90 to the passenger side. It is about a 45. When i got the angle right, i tack welded that piece in place after cutting the right length. Did the same for the other side but made sure the two would meet into the magnaflow y pipe. Once it was all in place i welded the pipe sections a bit further so they would hold shape. Dropped the whole setup and then welded, ground, cleaned and coated it. Now in my insanity or obsession, whichever term is fine with me, i have done this about 10 times so i am on version 10.0. The reason was for fine tuning the sizes, lengths, bends, and height adjustments. Each time it got easier and if anyone lived near me i could do it for you in an afternoon rather than the weeks i have been toying with it. Last thing is just the elbow to shoot the pipe up to the stack. Canada Customs is really pissing me off right now. Should have already been here.

 

what is a mandrel bend pipe and how do i get it... sorry not much experience with exhaust... at all

 

The tube is bent around a Mandrel, The mandrel allows the tubing to be bent into smooth curves without undesirable creasing, kinking, or collapsing.

Any good exhaust shop (can bend) or parts houses should carry mandrel bent tube sections.

-Enjoy
fh : )_~

 

Walker Exhaust 40573 - Pipe 1994 Ford F-250 | O'Reilly Auto Parts

based on this model that says it fits my (our) trucks other than the 2 obvious 90 degree bends what others would i need in terms of degrees and if possible length if im just going to buy the bent pieces and and weld it together on my own

 

they're showing you the good side.where the short pipe enters the long one,you can't see the steep turn it takes into it which causes back pressure.
in other words,might as well save your $,and don't do anything to the stock Y pipe,rather than go with that one.
its basically stock replacement,for those who don't mind factory,and need to replace a rusted out one.

even the high end kits,don't provide a good Y pipe that i know of.
you will need to make it yourself or have a shop fab it for you.

the reason why the Y pipes are simply a joining of the short side directly into the long side from the factory,is because its cheap to build.

i like the one this guy here took,where he placed the OEM and the custom side by side.it clearly shows the problem and the solution:

 

i know im wanting to make my own i just need demensions and angles i know you and wreckinball have pics and that helps but i need deminsions to really get going. im not going to slam the short into the long one like that im going to use an actual y pipe i just need to really know what degree those to other bends are the one close to the flange on the long one and the angle of bend on the short pipe

 

the guy who did mine said he couldn't make the pipe any larger up where they connected to the manifolds anyway,and asked me if it was ok if he just started with larger pipe welded onto them.i said yeah,cus because i wasn't concerned with the size here so much,cus its only half the engine per pipe.he did increase a bit,but simply went off those.
with the truck up,he cut off the pipes close to the manifolds,and took measurements as he went,back and forth from the bender.he adjusted and welded.then did the same for the other pipe.as they're different of course.
so id just kinda follow that method.
took him about 2 hrs start to finish.but he said he's done it a time or two before lol.
if your not going to make your bends but buy parts,id ask wreck for a complete pipe lists and part number, elbows 45/90,whatever,etc,etc lists or your likely going to be stranded with the truck for a bit chasing parts,and spending more $ in fuel than if you just had it built for you in the first place lol.

 

so id be ok leaving the 2.5 in pipe up there but change the T to a real Y and run the 3.5 from there back?