Spresso: you need to relo the DS O2 cabling! Do this BEFORE you install the header and you'll be much happier!
Group Buy - 100 Series Headers
- Thread starter uzj100
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would somebody post some pics of these installed already!?!?!?!?!?!?
Thanks! I'm right behind you...spent the last 1/2 hour trying to get that forward lower nut/stud out. Naturally it was the one that was REALLY torqued on from the factory
...just as I expected...all the others seemed like they weren't tight enough! I was able to get the heat shield out before removing the exhaust manifold as it really allowed better access to the manifold nuts/studs.
Taking a break before going back out to install the header. Thanks too for the heads-up on the engine mount!
Where did you relocate your cabling to?
Thanks! I'm right behind you...spent the last 1/2 hour trying to get that forward lower nut/stud out. Naturally it was the one that was REALLY torqued on from the factory
I was able to get the heat shield out before removing the exhaust manifold as it really allowed better access to the manifold nuts/studs.
Taking a break before going back out to install the header. Thanks too for the heads-up on the engine mount!
Thanks for the updates Spress, sounds like it's going relatively easy. I can only hope the same goes for when I get mine done/started this week hopefully.
I was anxious about this job due to the fact my rig came from a rust belt state and if I snapped/sheared/rounded off any of the nuts or studs the likelihood of having to pull the engine, especially for the limited access nuts/studs, was a very real concern.
You will need PLENTY of tools for this job. And I wouldn't even think about this job as a DIY IIWY if you don't have at least a good 1/2" drive impact (I also used my 3/8" drive impact for a few of the limited space/access nuts/studs).
Have 16-replacedment OEM studs on hand along with, of course, new nuts (along with header gaskets...mine were not reusable...and CAT pipe gaskets) unless you have zero rust on your rig...and even then you can always return unused parts.
Ditto! I went over everything I needed with Onur and ordered the parts last week, including the 16 OEM studs in case it gets ugly.
Regardless of the amount of heart I have in wanting to do this install myself, my mechanic friend agreed to take on this task. He has the proper tools needed in case the worst happens.
Thanks! I'm right behind you...spent the last 1/2 hour trying to get that forward lower nut/stud out. Naturally it was the one that was REALLY torqued on from the factory
I was able to get the heat shield out before removing the exhaust manifold as it really allowed better access to the manifold nuts/studs.
Taking a break before going back out to install the header. Thanks too for the heads-up on the engine mount!
oh good! The No. 1 nut I was actually able to get OK with a pneumatic socket IIRC. The buggers are the lower nuts on No. 5 and especially No. 7 when installing DS DT's!
You must have jacked your engine up higher than mine, I was a little chicken that I might smash something so I only moved it up about an inch which wouldn't let the heat shield come out the back, but it would go forward and out of the way.
For PS, just undue the two forward clips and there's enough slack to pull the factory harness rear toward the relo'd O2 sensor. Then zip tie to hard tubing running along block.
For DS, it's a similar drill. There are two brackets bolted to the block which hold the DS O2 Harness. Undue those and on that side the harness comes from up by the starter, so just snake it back under the heat shield and you have plenty of room. Then zip tie it to another bundle. In hindsight, I would strongly recommend you do this BEFORE installing the DT headers (much more room!).
Yep those lower DS nuts on the DT's are a biotch to get tight. If they were as rusty as my OEM there really wound not be a way to get the DT headers off sans pulling the engine and cutting the DT pipes out of the way to get full access to the nuts/studs.
Both headers are on...just need to lower the engine, bolt the CAT up and connect the O2 sensors.
OregonLC: Thanks again for the PS and DS O2 sensor heads up...that saved me a bunch of time and cuss'n
.
Both headers are on...just need to lower the engine, bolt the CAT up and connect the O2 sensors.
OregonLC: Thanks again for the PS and DS O2 sensor heads up...that saved me a bunch of time and cuss'n
.
Yep those lower DS nuts on the DT's are a biotch to get tight. If they were as rusty as my OEM there really wound not be a way to get the DT headers off sans pulling the engine and cutting the DT pipes out of the way to get full access to the nuts/studs.
Both headers are on...just need to lower the engine, bolt the CAT up and connect the O2 sensors.
OregonLC: Thanks again for the PS and DS O2 sensor heads up...that saved me a bunch of time and cuss'n
Glad you got it on! I just need to tighten everything up from the cat back and I'm done too, but first I'm going to take advantage of a break in the rain and get some leaves in the can! Dang fall weather gettin' in the way of my wrenchin'!
I just hope I indexed the steering shaft correctly or I may need to mess around with this more tonight.Did you tie up the AC hose that runs about 1/2" away from the DS header?
Everything's done except getting the #2 steering shaft reinstalled. For whatever reason...probably corrosion...I can't get the sliding coupler to move down far enough onto the steering shaft. Would SAS solve this?! 
Everything's done except getting the #2 steering shaft reinstalled. For whatever reason...probably corrosion...I can't get the sliding coupler to move down far enough onto the steering shaft. Would SAS solve this?!
So here's what I found: where the shaft meets the coupling next to the firewall, it will only go into a single clock position. If you look on the coupling, there is a slot on the back side (opposite the split) and I think it may be keyed. So to index it, you leave the upper coupling bolt undone (which allows sliding) and you clock it at the rack. Whatever the reason, I had the same problem and this seemed to fix it. I did lube all three splines which helped the sliding action.
I'm back and running. Started with no codes on the first crank! Driving impression: I guess I don't have enough regular seat time in the LC to be a good judge, but it wasn't a huge difference to me with the seat-o-pants meter.
Good to hear you are complete. I'm not expecting much...its probably hard to tell 25hp by seat o'the pants. However I DO notice considerable HP improvement when I go down to sea level
I didn't remove the sliding collar apart of this job...just the 2nd steering shaft. I'm going to start fresh tomorrow morning and figure out why the steering shaft won't go home within the collar. "Close but no cigar"
Good to hear you are complete. I'm not expecting much...its probably hard to tell 25hp by seat o'the pants. However I DO notice considerable HP improvement when I go down to sea level
I didn't remove the sliding collar apart of this job...just the 2nd steering shaft. I'm going to start fresh tomorrow morning and figure out why the steering shaft won't go home within the collar. "Close but no cigar"
Ya, Big Brown is a heavy beast, 25hp is a relatively small amount!
You'll probably find a better way to index it than I did if you start fresh! I tried forever to get the shaft to go back into the coupling and it would only go in one spot. Good luck!
My 900 mile Florida to Tennessee drive report:
Max MPG with new headers (hand calculated): 18.5 @ 70 MPH average
Max MPG with old manifolds: 17.5 @ 65 MPH
City driving: maybe 0.5 MPG advantage with headers
Power: Not much more power using the Ass-O-meter but it is definitely smoother. I also noticed that the torque converter stays locked up on long grades so it is good for the tranny. With the old manifolds I noticed that the torque converter unlocked all the time on long grades.
Overall value for the money: Good if your manifold(s) are cracked and need to be replaced. Bad if you are just installing headers for more power.
Max MPG with new headers (hand calculated): 18.5 @ 70 MPH average
Max MPG with old manifolds: 17.5 @ 65 MPH
City driving: maybe 0.5 MPG advantage with headers
Power: Not much more power using the Ass-O-meter but it is definitely smoother. I also noticed that the torque converter stays locked up on long grades so it is good for the tranny. With the old manifolds I noticed that the torque converter unlocked all the time on long grades.
Overall value for the money: Good if your manifold(s) are cracked and need to be replaced. Bad if you are just installing headers for more power.
Yes. One end of the coupling slides, the other is fixed. It slides up toward the firewall. The shaft side is fixed. You do, of course, need to remove the bolts completely from the firewall side of the coupling and the rack end of the shaft as there is a notch the bolt slides through. To get a good slide, I also loosened the shaft-side bolt on the coupling.
To get it off the rack you do need to articulate the u-joint just a little.
I would recommend pulling it all back out. Clean all splines and lubing them with some medium weight grease. Install the coupling on the shaft while out of the vehicle. Put the bolt in but only finger tight. Install the shaft, slipping the coupling onto the firewall splines first, making sure there is smooth up-down travel (don't forget the thrust washer! This will prevent the shaft from coming into the cabin and saying 'hi' in an accident!). Don't put in the upper bolt yet. Crawl underneath, push the shaft from below as far toward the firewall as she will go while articulating the u-joint slightly above the rack splines and then guide them down on to the rack. Install the lower bolt and then the upper, tightening all three.
- Thread starter
- #619
Installed
These were installed this weekend by a good friend of mine.
These were installed this weekend by a good friend of mine.
- Thread starter
- #620
Drive home report at 615 pm est in 80 degree weather. 170k miles. 285 bfg's, Bump it sliders at 180 extra lbs being carried around. 1/4 tank of fuel.
The first thing I noticed was how quiet my LC was again. It was scary how quiet the truck is now.
I have a on ramp at work on to 540, this was much easier with the new headers, not as much strain just more flow. Once underway, the roll on was much smoother and quicker. This is in 65 to 85 range. The truck seems to accelerate harder. The mid range is much improved. I would guesstimate by the seat of pants dyno that we probably gained about 10 to 15 hp. Feels back to stock with even with 285s and sliders.
Recommended if you have load leaky exhaust manifolds. The power gain is slight but makes the truck even more fun to drive. The V8 seems even smoother but I believe that all has to do with sound of leaky headers.
I cannot wait to start the LC tomorrow morning and no longer have it sound like an old farm truck.
Now, how do we get more air into the engine? I am thinking a duct under the passenger light that flows to the deck plate mod so it can be back to stock with ease. Thoughts?
The first thing I noticed was how quiet my LC was again. It was scary how quiet the truck is now.
I have a on ramp at work on to 540, this was much easier with the new headers, not as much strain just more flow. Once underway, the roll on was much smoother and quicker. This is in 65 to 85 range. The truck seems to accelerate harder. The mid range is much improved. I would guesstimate by the seat of pants dyno that we probably gained about 10 to 15 hp. Feels back to stock with even with 285s and sliders.
Recommended if you have load leaky exhaust manifolds. The power gain is slight but makes the truck even more fun to drive. The V8 seems even smoother but I believe that all has to do with sound of leaky headers.
I cannot wait to start the LC tomorrow morning and no longer have it sound like an old farm truck.
Now, how do we get more air into the engine? I am thinking a duct under the passenger light that flows to the deck plate mod so it can be back to stock with ease. Thoughts?
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