LC100 headers install and tcase regear

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I didn't read through the whole thread but is there a reason you didn't just go with new OEM manifolds? Seems they would bolt right up, mine have over 240K miles on them
 
I didn't read through the whole thread but is there a reason you didn't just go with new OEM manifolds? Seems they would bolt right up, mine have over 240K miles on them

Well sourcing a RHD version was kind of annoying but I did also want a little more sound (not a significant amount). I have a catback with wider tubes and was looking to match the tube size. The headers were a bit more money than oem but I have read that OEM replacements are hit or miss on longevity. but you're right, oem would have been significantly easier to deal with. That would have probably been a 2-3 hour job max.


right now im stuck at two places so will work on a few other things in the meantime. I have to wait for heater tees and for the new tcase seal. Im pretty much done with the headers but this is what I need to do to be complete with this job (more of a checklist for me):

Transfer Case​

☐ Install new input seal
☐ Repair speedo
☐ Finish assembly
☐ Verify shift motor gear orientation
☐ Clean shift motor mating surface
☐ Reseal shift motor
☐ Reattach the linkage/bar that I messed up earlier in the project

Cooling System​

✓ Dump coolant
☐ Replace broken heater tee with brass tees
✓ Inspect nearby heater hoses and hope everything else is good
☐ Refill/top off coolant

Driveline​

✓ Dump trans fluid
✓ Prep driveshafts, they need to be cleaned badly
✓ Grease U-joints/slip yokes
☐ Figure out how to orientate them correctly without match marks

Install Case​

☐ Install transfer case
☐ Reconnect linkage
☐ Reconnect speedometer sensor wiring
☐ Reconnect shift motor
☐ Install front+rear driveshaft

Exhaust​

✓ Install second o2 sensor extension
☐ Install new cats
✓ Double check o2 wiring clearance from headers
☐ Install midpipe
☐ Tighten all exhaust connections

Final checkover​

✓ Reinstall air intake
☐ Reconnect battery
☐ Verify transfer case in correct position
☐ Coolant level check
☐ Fill tcase
☐ Refill transmission fluid

Looks like a big list but it shouldnt be that bad. I think I'll dump coolant and get the driveshafts ready today
 
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The heater tee that busted was in bad shape. It crumbled just squeezing it a little bit, I needed to replace that anyways. The other is fine. The new brass ones come in tomorrow, fairly painless install thankfully

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The fluid was nasty so I decided to go ahead and dump my coolant. I dumped the rest of my trans fluid too as I didn't know what type was in there and didn't wanna mix them
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This is how I chose to route the O2 extensions, driver's side:
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Passenger side
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I'm unsure about the second picture on the driver's side, I doubt that's gonna stay there. I don't know if it's ok to drill into that metal though. I'll think on it some and figure out a solution
 
I tried sanding the rust off my drive shaft but instead the paint came off..so I just sanded the entire things
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Painted and then greased (no, no paint in the grease fittings):
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Really questioning if greasing them prior to install was the right choice, they're incredibly difficult to compress. I might remove the grease and regrease once they're installed

Tomorrow my replacement seal comes on for the tcase. I work all day the next five days so probably won't be done by the weekend but I'll make a bit of progress each night.
 
This thread has taught me that if I'm going to rear gear my t case have valley hybrids do it.
I might have done that if I weren't on the opposite side of the country. I am an inexperianced home mechanic though, and this was tackling two big jobs at once. I work 7:30-7 five days a week, so I can only put a few hours in most days.

While the thread has been drug out over two weeks I think most guys here would have knocked the tcase out alone in a day or less, I just don't have the experience and I'm a little meticulous in cleaning and making sure things are done to the best of my ability

also the headers were a lot worse than the tcase imo :shifty:
 
Been a few days but I'm making progress. I got the transfer case seal in and replaced it.

Put as much coolant in as my car would allow without cutting it on and poured 4 qts of ATF in the trans.

Got my heater tees installed
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Got most of the case together after work today
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Have to wait for the FIPG to cure before I can do the servo. Can do that tomorrow after work and hopefully wrap up this project to have a car to drive by Monday

At this point I just need to:
-install servo motor
-install tcase
-install driveshafts
-install cats and midpipe
-run to warm for coolant and transmission fluid & top off as necessary
 
Write up on the headers.

Tools/Parts needed:
-Left hand drive headers and cats ($1020 usd) or Right hand drive headers and cats ($980 usd)
Shipping to the east coast was about $300. I also had to pay fedex $240 for import fees/ dutys
-Oxygen sensor extensions. The description says that you don't need them, you do
-E10 female torx socket, must have (here's the set that I used)
-Medium height 14mm socket
-Deep socket 14mm socket
-14mm stubby wrench, you will not get the job done without one. I got this set
-An extension set for 3/8th drive. I used a 2 foot extension and combinations of these
-Swivel joints, included in the set linked above
-You may need extractors if you are in the rust belt. I bought this kit, but didn't end up needing them
-Impact driver
-2 foot breaker bar and 3 foot breaker bar
-90126-10015 stud x16
-90179-10070 nut x16
-17mm wrench and a socket


Process:
Keep in mind during this that I have a RHD UZJ. Mine does not have EGR.

First things first, jack up the car and remove both wheels as well as splash gaurds. The job is impossible without this.

You will need to then remove the midpipe bolts and the cats. I opted to use an impact to break them off and it was fairly quick. It took longer to disconnect the o2 sensors than to remove the bolts. The Rhino kit comes with new bolts and gaskets.

Next, get rid of the heat shields. There is four 12mm bolts on each one, they aren't too bad to get to from the wheel well. Getting the heat shields out is a lot worse, though. I found it easiest to wedge them up to the front of the vehicle, and push them down. You will have to sort of wedge them between the fan blades and be careful of the radiator

Drivers side:
The drivers side was easy, except I made some mistakes. Remove all 8 nuts from the OEM headers, they aren't too horrible to get to. The top ones you will use a 14mm deep socket and a breaker bar dropped down from the top of the motor. The bottom ones you have to get a bit creative. You for the rear two I used a swivel joint and the impact gun from the wheel well. The front two were a bit different, you have to use long extensions from the bottom of the car with a swivel joint

If you don't live in the rust belt, you aren't going to have issues getting the nuts off. If you do, use your extractors. On both sides the OEM headers will slide right out from the rear where the cats were with no issues.

For installing the rhino headers, you will need a bit of prep. Go ahead and drill/file the outer most holes on the outer most sides of both headers. This will save you a significant amount of time
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-Use your reverse torx bit to go ahead and remove all the studs
-Clean the mating surface of the motor with brake clean and 000 steel wool
-Install all studs except the rear most top two studs
-Mount your headers on the studs, you should have plenty of clearance
-Install your rear most top two studs with the header on the motor
-START all 8 nuts, then hand tighten the bottom nut second from the front first. If you dont do this, you will find yourself in the situation I did below where a wrench will not clear it
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-From here you are going to use a normal wrench and extension from the wheel well on the top 3 rear most nuts, a stubby wrench on the front most top nut
The bottom nuts will almost entirely be stubby wrenches except one, you have to access it from a gap below your cv axle with a long extension and a swivel:

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Passenger side:
Removal of the OEM one is basically the same as the driver side and took me about 15 minutes.

Go ahead and save your self alot of effort and trial and error. Remove all studs, clean the surface, then just go straight to removing the 3 nuts on the motor mount. Lift the motor from the bell housing between the motor and the trans about 3 inches, until your fan blade is about to touch the shroud. Be aware of your heater tees, mine broke during this.
sa
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This will give you the clearance to get your headers in. Just like the drivers side, put all studs in except the two top rear most studs. Mount your headers and use your female torx bit to mount the two remaining studs.

Mount your headers and go ahead and start all the nuts, this part is a lot worse than the other side. You will have to use a stubby wrench for just about every nut (except the top two rear most- those are from the wheel well. Most of the bottom ones will be accessed by laying on your back and blindly starting them by hand.

This side the headers are shaped different, and the first nut you will actually tighten halfway, that's the frontmost bottom two nuts. I did each a little bit at a time until I couldnt tighten them by hand.

From there I went ahead and tightened the remaining by hand until I couldn't any more.

After that you will basically use the stubby wrench for every single bolt. The bottom nuts that are second and third from the front you'll have to use the open end of the wrench. You can't see while you're doing this and if it's anything like my experience you'll spend 30+ minutes on each nut. The top rear two nuts, and the second rearmost nut on the bottom are easily accessed from the wheel well and you'll have no issues with them.

Once you've successfully tightened each nut as much as you can with little to no leverage, you're going to have the pleasure of getting your motor mount back on. Get the three nuts started so that everything is lined up, you'll have to lower your motor a small amount first.

From there lower your motor a small amount, hand tighten them, and repeat that a few times until the motor is off of the jack. You have to pry a wrench between the headers and the mount and tighten it with the open end a very small amount at a time, it's a frustrating process and takes a while because you'll likely be laying under the car doing it blindly

From here it's easy. Just install your sensors and route them away from heat to the best of your ability. Install your cats with the nut side facing the motor.

This job doesn't require any technical skill but it does require some specific tools and a lot of patience. I wish I could have taken more pictures but the space that you're working with is super tight
 
Feedback on headers and tcase regear


Probably my last post on this thread unless people have questions:

The regear- I can't experience low range yet because I misaligned the teeth for my actuator and CDL won't engage. The high gear isn't quite what I was expecting, but it's been nice. It's a little bit more 'power' up front when taking off and driving around town. I'm on 33's and the RPM at highway cruising speed is like 2400. There is a whining noise, that is constant. If your windows are up you wont hear it at low speeds but while they are down you certainly do, the faster you go the louder it gets and it is somewhat intrusive

The rhino headers:
I probably would have just gone OEM if i realized how much of a headache they would be lol. The ticking noise is gone though, thats pretty nice. The sound is different. It's really not much louder than OEM headers but it is a deeper rumble kind of noise- my finance has no idea what i've been doing with my car and she didnt even notice the difference in volumn. I do have an aftermarket catback with THREE mufflers (one of them is massive) so ultimately it's still very quiet, but it does have a very nice sound to it. I'm considering deleting the large muffler or installing a smaller high flow muffler for a bit more noise.
 
Should be able to go in Low range no matter if CDL is locked/unlocked, no?
I honestly haven't tried, I was under the impression that the 100 series automatically engages CDL when you put it in low and I didn't want to potentially cause any unnecessary issues until I fix the actuator
 
Ah... the US market 98-02 100 will indeed automatically try to lock the CDL when in LOW range. I don't know how it is for JDM. However, many, including myself have done the "Pin-7" mod which stems from the 80 series days. It allows the HI/LO transfer case selection and CDL to be independent. So you can have LOW range and not locked but better maneuvering. Be advised, I have engaged low range and forgotten to lock CDL on some occasions which can result in one wheel spinning in the air until you realize what is wrong.

If you want to play with Low range, just unplug the CDL actuator for now. Pin-7 mod is almost as easy.
 
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