[baktasht]

Originally Posted by Ebag333

It is the upper rear control arm (where it bolts onto the axle). You can see the arm in the pic I took, it's the one with the wiring harness zip tied to it.

The OEM exhaust swings much more toward the center to avoid that. Even just moving it inboard 3-4 inches should clear it.

Also, if you've extended your bump stops then you'd be less likely to hit it, I would think. I have not extended mine as I want to keep as much up travel as I can.

Thanks for the input there, let me know if you have time to look at it further and what you find.

Originally Posted by smokethedog

any plans for a 3"?

Not at this time. For the naturally aspirated guys, the mandrel bent 2.5" system we've got setup is more than enough. For the supercharged and turbo charged guys the 2.5" mandrel bent setup we have is also a great match for anyone making up to around 350whp which is quite a bit. Unless you plan on getting larger injectors and an aftermarket ECU, and get it all tuned for your setup, you will probably not get power greater than that. Also keep in mind that a typical crush bent 3" exhaust probably flows near what our mandrel bent 2.5" exhaust does.

[CycloSteve]

Hi All, mine will be going in sometime next week hopefully, and will see what the clearance looks like.

I was already considering having a local shop re-work the last section of pipe for my rig, as I think it will hang lower than I like with the 4x4 Labs bumper anyways. A few cuts, rotation, and perhaps a bend or two of mandrel-bent pipe should do the trick, and will feed the info back to Baktash for future production models.

Perhaps there will be a "stock" rear section and one for those of us with aftermarket bumpers, etc.

[baktasht]

Originally Posted by CycloSteve

Hi All, mine will be going in sometime next week hopefully, and will see what the clearance looks like.

I was already considering having a local shop re-work the last section of pipe for my rig, as I think it will hang lower than I like with the 4x4 Labs bumper anyways. A few cuts, rotation, and perhaps a bend or two of mandrel-bent pipe should do the trick, and will feed the info back to Baktash for future production models.

Perhaps there will be a "stock" rear section and one for those of us with aftermarket bumpers, etc.

Yup, future versions will more than likely have a couple of different tailpipe sections available

[Christopholi]

Any test fit on a 94 yet? How does it deal with the two pre-cat 02 sensors on that model? from the pictures, it looks like there is only one post-cat sensor.

[baktasht]

Originally Posted by Christopholi

Any test fit on a 94 yet? How does it deal with the two pre-cat 02 sensors on that model? from the pictures, it looks like there is only one post-cat sensor.

Nobody has test fitted with a 93/94 yet. We'd just put additional O2 bungs on there for the additional sensors. If you're up to do a test fit drop me a message.

[CycloSteve]

OK, pipes are back in my hands now...trying to source and install EGT and Widband bungs before the install...one step closer, and keeping my patience hat on.

Any thoughts on bung placement, other than pre-cat? Figure will put them inboard after the Y and out of the way from harm as best as possible.

[baktasht]

Originally Posted by CycloSteve

OK, pipes are back in my hands now...trying to source and install EGT and Widband bungs before the install...one step closer, and keeping my patience hat on.

Any thoughts on bung placement, other than pre-cat? Figure will put them inboard after the Y and out of the way from harm as best as possible.

For EGT you want to put it as close to the head as possible. In the exhaust manifold itself is usually preferable.

For wideband, put it right after the y-pipe joins into one pipe.

[CycloSteve]

Hmm, with the two cast iron mani's buried deep below the SC, I think I will have the EGT bung placed just after the Y. Losts of debate out there about placement (the hotttest exhaust runner vs. collector), but in my case I think that practicality of the pipe being out of the truck is the deciding factor...plus down there is likely accurate enough for the changes I am interested in being able to follow.

[baktasht]

So..... Anyone with a diesel 80 series around that can send me some detailed pictures of their exhaust setup? Particularly right around where the muffler, the cat, and he piping that connects to the at are?

[Ebag333]

Originally Posted by baktasht

So..... Anyone with a diesel 80 series around that can send me some detailed pictures of their exhaust setup? Particularly right around where the muffler, the cat, and he piping that connects to the at are?

http://forum.ih8mud.com/80-series-te...portunity.html

[gabe74gt]

I have the same magnaflow too and love it, you can usually get a used one on ebay or cragislist. I wanted a valid warranty so I got it here. Magnaflow 23969. Also some of the forum sponsors usually have a sale going on. Either way its a great exhaust system, sounds great, and very easy to install.

[CycloSteve]

Mid-install at present...everything came out OK with a liberal spray of PB and four-hours of soaking time. Nothing broken along the way other than a little skin Just a lot of parts and tools on the garage floor, as sourcing a few final bits and pieces. Will post more later in the week when finished...then off to 034 for the Dyno test next Monday.

[CycloSteve]

OK, the system is in, and have about 150 miles on the truck so far.

Here are the details regarding the DIY install, and how things went in general

• Didn't even have to bother with jack-stands or putting the truck on a lift, as she is high-enough to reach all of the system from the garage floor/creeper.
  
• Removal of OEM system took about 1.5 hours, being carful not to break anything along the way. Sprayed with PB Blaster about 4 hours in advance, and a quick shot just before removal.
  
• The only special tools that I bought was a 20" 1/2 inch extension and 1/2" deep sockets (needed them anyway), which made reaching the nuts at the top of the Y-Pipe easy. Otherwise only used standard set of metric sockets (shallow and deep) and wrenches. Also had a good 1/2" torque wrench to be sure that all was torqued to spec.
  
• For those with sliders, you WILL need to remove the PS...tried to get the over-frame pipe in with the slider installed, but no go.
  
• You will need to remove the OEM rear tailpipe mount (not used any more), the factory Y-Pipe bracket, plus the rubber mounts from all of the other mounts (post muffler, and post-cat.
  
• Installation-wise, I chose to install the muffler-section first, then the over-frame. Then the Y-Pipe, and finally the tailpipe.
  
• One change from the system on Ebag333's rig is a set of pivoting flanges on the Y-Pipe and over-frame connections. These will allow you to orient the system to your needs.
  
• With the tailpipe, that came last as I had 3.5 inches removed to bring it up, forward, and inwards! All which help it to work much better with the 4x4Labs rear bumper; likely this mod will also work for those with Kaymars, and Slee's. Yes, it is still a pinch-point, but only in extreme wheeling, where I would take that section out in anycase.
  
• Note on gaskets; used 2.5" header collector gaskets between the muffler and over-frame, and the Tailpipe and muffler section. No gasket needed with the re-engineered. Y-Pipe to over-frame; just twist the fitting to the way you want it to be, and tighten up evenly. Gas-tight seal. Used OEM donut style gaskets from the Y-Pipe to Manifold, though may change to a larger one.
  
• Hardware-wise, reused the OEM nuts for the Y-Pipe to Manifold, and also with the O2 sensors. New metric hardware for all other parts of the system.
  
• As with Ebag333's rig, the system is hard-mounted. The over-frame bolts to the inner hole from the OEM mount, and the muffler mounts to the outer hole of the OEM mount. The rear actually mounts to one of the OEM nutserts which also serves duty to mount my 4x4labs bumper.
  
• Other than the change above to the tailpipe section, I also had bungs welded into the system for EGT and Wideband sensors.
  
• Needed to make several changes to the O2 wiring loom. Removed from the frame, and moved the front sensor plug about six inches forward in the loom, and then re-taped the plastic frame clips in the right place, and zip-tied the rear sensor wire well out of the way. Also decided to move the "guard" to the front sensor so that any rocks or other things flying off of the wheel would hit that first. Will get another one from CDan for the rear.
  
• The whole "install" process was perhaps 3 hours, since I was taking my time and checking everything three times for clearance, torque, issues, etc.

Post-Install Startup and Impressions

• Definitely much more sound than from the factory. Will post a sound-bite on the Dyno thread tomorrow.
  
• The hoover sound is gone. Sounds more like a truck.
  
• Mystery rattles in the old system gone!
  
• Fitment is great. The only area where it is close is at the transmission dampener, where there is only 3/8 to the rear-nut. Trust me, it is OK, and don't take out your dampener as I did, you will only put it back in.
  
• Clerance above the pipes is at least 1.5 inches, often much more, yet the system is tucked a good two to three inches higher than factory due to the over-frame design. IMO there will likely be less passenger side floor heat, as there is more space for air to circulate.
  
• I don't think that the over-axle section will hit the upper links with mine, as it appears to be a few inches inboard from Ebag333's...and did a quick articulaton-test, and no dent so far. Nothing extreme, but no dings with the PS rear on the bumpstop.
  
• The only "new" sound is a very pronounced whistle. Working with Baktash and a local fabricator to resolve; it is likely a simple change at the top of the Y-Pipe needed to match OEM (1cm tube extension into the manifold). Will also make the installation of the gasket more simple and accurate (no guesswork on centering them). All part of the "D" part of R&D and Beta-Testing.
  
• Slightly more vibrations coming through the floorboards from the exhaust due to the hard-mounts; nothing bad, just a bit more "feel."
  
• Butt Dyno says more power...will see what the real Dyno says Monday at 5pm!

Suggested changes for the production units

• Move O2 sensors upwards for ground clearance, as there is room up there.
  
• Several tailpipe versions (discussed above, and exact details going to Baktash)
  
• Rework Y-Pipe as noted above to curtail whistle and expedite gasket install
  
• Add WB O2 and EGT bungs to the system (with plugs)

For those wondering about the cost, you will spend less that what I have on the unit iself, time, shipping, and a few custom modifcations at the local fab/speed-shop. Again part of the R&D effort.

The install falls into a category/ IMO if you can use a wrench you can do this one yourself. Easy to do by yourself, as not really any need for a second set of hands. Can be done on a Saturday morning, and be back on the road after lunch.

So here are a few parting shots, with the whole album which can be found here:

http://forum.ih8mud.com/members/cycl...d-exhaust.html

More video and sound bites tomorrow with the post-installation Dyno test...

Rear View



Side View



Underview from Rear



Completely out of the way!

[Ebag333]

Check your Y-pipe studs/nuts after your next wheeling trip. Mine came loose, but that may be due in part to someone else wrenching on my junk....

I still have some reservations about the hard mounted system, but after I fix all the joints and mounts I will revisit it.


Excellent write up by the way, you've put me to shame.


As a follow up I'm still loving the sound of it, and have gotten plenty of compliments on it.

[CycloSteve]

OK, results are in...and posted in the Dyno thread...well pleased to have some confirmed extra HP under the bonnet!

IH8MUD.com - View Single Post - Dyno Results