mh64

Alright so after reading through a few threads on here about what to do with the 5.4's exhaust (@Jbrew had a great write up about how to trade in your old cats and put in a new system so thank you for that). However, my truck has some rusty studs, like many others. My question is this: If you use Kroil or your trans fluid/solvent mix for a week or 2, spraying generously every few days, whats the likelihood they come out clean? I know you can drill them out but to be honest im not the greatest taper and driller lol. But I can take them out (I.E. double nut method or vise grips) then throw in the long tubes and new cats and call it a day. One more question I have is will I get a check engine light with just 1 cat for each side? And lastly, are there any exhaust studs you guys would recommend? Thanks

Anthony Kadzban

I ran my truck for three months without cats before I had to reset the computer and finally got the first CEL. I keep a cheap OBDII code reader/ eraser in the truck and have to clear once every other tank of gas. You're looking to clear p0420 and p0430. I'd look for a stainless steel stud and nut combo.

Take the inner liner out of the wheel well and you'dd be able to access the top four studs from the top and I found it easier to get the bottom studs from the underside of the truck with a ujoint and a few extensions.

When I pulled all 16 of my studs, I gave it a pb blaster bath every night for a week and didn't snap any off in the head. Because the head is aluminum, I was able to weld a gob onto one of the broken studs to build metal up to where I could put a weld an old nut onto the stud and start to back that out with a socket - not needing to drill and tap a hole. remember that aluminum melts at a lower temperature than steel so be cautious when really going to town. If you do need to drill a hole, a helicoil thread system works nicely when installed correctly.

But the more I've read about this, it seems that the transmission mounts seem to wear out, pulling down on the back of the motor, putting the wrong type of forces on the manifold studs. Anyone else seem to confirm that?

If you go with long tubes, Summit Racing also sells a y pipe that bolts directly to the long tubes. I don't know if there are provisions for O2 sensors, but those bungs are easily welded to the pipe after drilling a hole. Then you have a single pipe under the passenger seat where you can start to add a muffler and tip.

white89gt

It's hard to say without knowing the condition of yours, and what a PO may have done (i.e. cross threaded the stud or nut). But based on personal experience, I've never broken a stud, bolt, or spark plug while using Kroil. Their slogan on the can says "the oil that creeps" and I would absolutely agree with that.

mh64

Thanks man, and yea problem with the code deleting is it still will come up on emissions testing. and I would still like cats. Do you know if 2 cats is enough? and yea the transmission mout is something i intend on replacing soon.

mh64

Yea I will definitely be ordering some of that when the time comes, I didnt know such a thing existed but after reading reviews online about it, it looks like its all business.

white89gt

Yes, two cats are enough if you buy new 3 ways. Someone correct me if I am wrong but I believe the front two are just preheaters on our trucks. A 3 way would have that process all in one cat.

mh64

Jbrew had a write up of what he did, I believe he used the factory tubing, pacesetter makes a y pipe to fit these, and I figured I would put cats into those. I know you have to extend the O2 censor length by like a foot but apparently the kit comes with everything you need. Only complaint I found about them was that you should strip the old paint off and use high heat paint. but I really want to do this because I know the factory set up is very restricting.

ScrewThat

Yeah it honestly just depends on how bad your specific studs are. Mine were somewhat rusted but not bad at all. I still gave mine the 50/50 acetone atf bath in the morning before getting ready for work. I'd let the acetone evaporate off then drive to work. I did that about every other day for a week or so before my long tube install. I didn't break any studs while removing, but I did have one that was already snapped so I had to reverse drill and use an extractor to get it out. Luckily for me it was one that was easy to access.

Whenever you replace the manifolds with the long tubes id recommend using stage 8 locking hardware. They're bolts instead of studs and have a tear drop shape clip that rest against the headers to keep them from spinning out. Hell id even use them if I were going back to stock manifolds.

Do not use the wire that the headers come with. Buy extenders or buy o2's with a longer harness. I'll post a link for some extenders that work well. I used them on my install. I had to file off the plastic legs on the outside for them to work with the truck sensors but I'm pretty sure you can buy mustang o2's and they should work. I have the truck o2 sensors in my mustang at the moment with no issues.

O2 sensor extenders

mh64

Awesome thanks and yea I was just looking at that hardware on amazon, its about 50$ but looks quality. I also saw one guy get the nuts off of them then heat them with a torch, and the heat expansion and contraction broke the rust free inside the head, dont know if this would work and I will try to go get a few pics of my manifolds.

mh64

The first 2 are a few of the tops on the passenger side, 3rd is the driver side. Passenger side doesn't look to good.