[jim_5820]

I've been trying to get the 4" downpipe installed on my 2000 F250, 7.3, manual trans for days. The new porta power arrived today, and I neatly bent the flange back. I'm still not even close to fitting the 4" downpipe. The whole area of the firewall would need to be bent back by quite a bit.
My stock downpipe is 3" OD, and I'm strongly considering putting it back in. Then I'd build or buy a 3-4 inch adapter and finish it out with the 4" pipe and flow-thru muffler. I removed the IAH and wires and plugged the hole with a Cummins drain plug shaved off so it doesn't stick into the airflow.
I am doing a Hydra Chip (EGT sensor is in) and plan on running a 40 hp or maybe even the 60 HP tune. Everything else is stock.

Any thoughts on this plan?

 

[mcnance865]

I replied to your other post about the downpipe, must be an issue with spacing due to the ZF6 I am not familiar with. I did not have to modify anything to fit a 4" downpipe on my 2000.

As for the hydra, assuming you have an EGT gauge, I'd run it on the hottest tune. You get the best mileage there if not beating on it like a teenager. If towing, I'd back it down. I'd probably spring for an S&B air intake also to go along with your 4" exhaust. Either of these on their own make small differences, but the real difference is when they are combined IMO.

 

[jim_5820]

mc, thanks for the response. It may be a combination of things: Manual tranny, old, mashed cab mount rubbers, cab slid forward in the mounting slots, who knows. All I can say is I don't see how this 4" pipe is going to fit. I read one post where everyone said that removing the tranny cross member makes it easy. When I try to go up and in as if the member isn't there, it still hits stuff. Very frustrating.

 

[JGK]

When I had to redo my exhaust because a PO went to four-inch regular steel after the downpipe, and it rotted out, I wanted a 3 1/2 inch downpipe to 4 inch. Seems that not too long ago, 3 1/2 inch DPs were widely available.

And when I had to get a wrench up to loosen one of my bell housing bolts to work on the transmission dipstick tube, I was really cussing my 4 inch that I didn’t really want in the first place.

 

[Maryland dieselnick]

When you contemplate using a porta power.. It’s time to get out of the heat, crank the AC, drink some water and take a nap.
Block all wheels, suspend trans with TWO heavy duty ratchet straps. Remove the cross member. Cut the studs on the first horizontal joint. Remove passenger side wheel. Jack that side up high. Place a jack stand on that side of axle tube. Place jack stand under frame rail where passenger side door is up towards where meets the fender. Check the blocks in all three wheels. Remove clamp at turbo. It will drop out. Kiss your truck. Give it a gentle Pat and promise it that you will never go full on Viking on it ever again.

 

[jim_5820]

When you contemplate using a porta power.. It’s time to get out of the heat, crank the AC, drink some water and take a nap.
Block all wheels, suspend trans with TWO heavy duty ratchet straps. Remove the cross member. Cut the studs on the first horizontal joint. Remove passenger side wheel. Jack that side up high. Place a jack stand on that side of axle tube. Place jack stand under frame rail where passenger side door is up towards where meets the fender. Check the blocks in all three wheels. Remove clamp at turbo. It will drop out. Kiss your truck. Give it a gentle Pat and promise it that you will never go full on Viking on it ever again.

I'm not sure you understand the issue, but I appreciate your input - I'm trying to stuff a 4" downpipe up into a space originally designed for a 3" pipe. The stock pipe was out three days ago. The truck is a 4X4 and has leaf springs on the front and rear axles. I mention this because the rear shackle on the right front spring set is also in the way - depending on how I rotate the 4" DP as I try to find a way to get it up in place. The porta-power was used to get the firewall flange bent out of the way - which it did very well. It's still not enough, though. If the manufacturer had made a splice at the end of the lower bend instead of the long bit after the elbow, I think it would go - that's what I plan to fab up tomorrow - a splice with a sleeve welded at the DP end where I cut it and then I can clamp the short piece that goes over the cross member.

To be clear, It's not the cross member that is the issue - the long bit after the lower bend hits the truck's frame when I rotate the pipe to a position that clears everything up in the engine bay. Cutting this off should do it - then I'll install the rest and clamp it well - maybe a few tack welds to boot.
This stuff is tough to explain

 

[Maryland dieselnick]

I’ve done a bunch. Some with manual transmissions. I had one customer that had me redo and update everything before he went to Alaska was one that was a manual. It did a 4” on his. I think I even did a wrap job on it. I do them all the same except some don’t opt for the wrap job. Kevin the administrator saw it in Alaska.

 

[Maryland dieselnick]

It’s 10:30 here. I’m turning in. I’ll check on you tomorrow.

 

[jim_5820]

I'll be checking in.

 

[klhansen]

I replied to your other post about the downpipe, must be an issue with spacing due to the ZF6 I am not familiar with. I did not have to modify anything to fit a 4" downpipe on my 2000.

It doesn't have anything to do with the ZF6. I put a 4" downpipe in my truck and it's a 4x4 as well. I think there's actually more room around a ZF6 than an auto tranny.
I don't recall specifically looking at the exhaust on Nick's buddy's truck when he came by here, but overall it looked very nice.

Jim, you're either not holding your mouth right or there's something up with the exhaust kit you bought.

 

[Maryland dieselnick]

Don’t cut or beat on anything.
Im telling you if you follow my instructions exactly, you will do it without hacking things up and making a mess.
When the cross member is gone, the engine is not tilting back to the firewall as much. In fact your ratchet straps will move it forward.
When the right side of axle is jacked high, that shackle rotates down and forward. You also gain all sorts of ground clearance. I’ve done many 4”s.
Im a diesel and hydraulics mechanic. I’m not guessing.
Do not forget to set your parking brake, to block the 3 wheels, to recheck the blocking of the wheels and placing of the two jack stands.
I am not responsible for you or anyone getting injured. Don’t forget gloves and goggles.

 

[Maryland dieselnick]

I found a picture of the manual transmission truck that Kevin saw that I put a 4 inch on and I also did a triple heat wrap on it. If you look closely, you will see that it also has an aluminized heat wrap overlay over the triple wrap on the vertices section

 

[Maryland dieselnick]

Jenny McCarthy saw it as well.

 

[jim_5820]

You guys are great, and I appreciate you sticking with me through this. I'm not new to mechanical obstacles. I was a class A Millright for over 20 years and know how to shoehorn square pegs into round holes. I also think Diamond Eye provided the correct parts. That said, I think the truck may have been through a few rough patches in its previous life (I bought it used), and everything may not be in its "factory" position. Removing the cross member and lifting the transmission makes a lot of sense - the motor mounts are about 8 inches forward of the back end of the engine so jacking the tranny should move the engine away from the firewall a bit. The issue with the spring shackle is only when I rotate the pipe a specific way and I don't think that I will need that angle if you get my meaning.

I'm off to remove the cross member and will use a floor jack to lift the transmission, rotate the motor away from the firewall, and with any luck slip the pipe in. I'll use a small ratchet strap to hold the pipe up while I put the band clamp on as I'm working alone.

I will report back a bit later - I work slow.
Jim

 

[Maryland dieselnick]

I have seen a punch press that is the size and power that gives little boys nightmares, punch a one inch hole in a one inch thick plate like it was butter and it looked perfect. Now putting square things through round holes…. Albeit impressive, it’s not the best mentality to have during this task.
You need to be extremely careful jacking like that. It could cause damage. I wrote to use two large ratchet straps. I did write because I assumed that you would know to : Go up and over the frame rail and hook to the inside of the lower frame rail, to do the same in other side, while using two ratchet straps. ( clearly my mistake). That load should be spread out to prevent damage and for your safety.
I suggest following directions and not deviating from them. You have questions, stop. There are people here to help. Il check on you when I stop to sit.
Millwright that likes to go rogue. Millwright that tries to put square things through round holes. Definitely seeing an issue here. Do you still have all of your digits?

 

[jim_5820]

While I value your input, just because I'm not following every detail of your instructions doesn't mean I don't know what I'm doing or how to work safely. I have the cross member off, and the transmission is jacked up against the tunnel - it's not going up anymore without lifting the truck. The pipe still won't go. It is slightly better but not enough. My analogy of the square peg into a round hole refers to Ford's design for a 3" pipe and my desire to replace it with a 4.
It is clear from the myriad of posts I've read that in most cases, the pipe fits - many don't even need to remove the cross member. Why this truck has less space, I can only guess, but because it does, I will have to resort to non-traditional means if I want this 4" bolted to the turbo.
I am proceeding with my earlier plan of cutting the pipe and fabricating a splice. I may need to remove the pipe someday to change the clutch. The splice will make removing the pipe much easier.

 

[jim_5820]

I cut the 4" DP at the end of the lower bend radius - the DP slipped right in , and because the pipe was much lighter, I could hold it in place while I installed the band clamp at the turbo. I don't know if bending the firewall flange back helped, but it didn't hurt. I lowered the transmission back to where it was, and everything looks to clear well. I have ordered a stainless steel 4" band clamp kit with weld-on flanges - should arrive Sunday, and I should be able to wrap this up. This is the way it should be made from the start. As I mentioned, removing the transmission would be tough as the pipe limits access to all the bolts. With the v-band at the elbow, the pipe will be easy to remove. Also, the new splice will allow DP removal without taking out the cross member.
I will report back with pictures once it's all done.
Here is where I cut the 4" DP

Cheers

 

[Maryland dieselnick]

Once you have been here for awhile, you will realize that I feather in sarcastic humor.

 

[jim_5820]

No worries, I appreciate everyone's input. I just have an odd truck that required an odd solution. I am glad I stuck with it, though, rather than putting the stock DP back in. My goal is reasonable EGTs at 60+ MPH while towing 7K up long 6% grades. The Hydra chip will help but not if I have backpressure after the turbo. I may need to improve the intake filter - we'll see how it goes.

 

[mcnance865]

Looking at your pictures after you cut the down pipe I remembered that that is how mine came already (it was a Bullydog kit). The only thing I had to touch was removing the existing downpipe (and the rest of the exhaust obviously) to get the new downpipe in there from the bottom. Glad you got it figured out.