Pertaining to the title. I'm installing a new Weapon-R Header with Cat+Cat-back. However, since I live in the DMV area, they spray chemicals and salt all winter and it rusts absolutely everything. So, I wanted to change out all the bolts along with it just so I don't put bad bolts back in and if I have to mess with it again in the future. Unfortunately, I can't find any definitive size of bolt or studs anywhere. The manual online says it has 3 bolts in the middle and two nuts on the ends; I'm supposing are connected to removable studs. I'd like to put in stainless steel nuts and bolts/studs so I don't have to worry about rust as much but I can't actually find the complete size. Any help would be appreciated.

 

Have you looked on any of the Scion parts sites for part numbers or measurements...if you find the part numbers you can likely find a picture of the package on Google Images and it might have the part number or you might be able to search the part number for a size. I don't think there's is any compelling reason that you need to keep the studs but I haven't looked to be sure.

If you're going to use stainless bolts/studs in an aluminum head I would sure to use lots of anti-seize also.

 

Yeah, Uncle taught me to use anti-seize everywhere I can when I worked with him. I somehow get it everywhere on me, but definitely worth it. You've never known pain until you spend 2 days sledgehammering a 100-pound nut off an arbor bearing because clients don't follow protocols when reinstalling parts... Nah, every diagram I can get a hold of just ends at a picture of the manifold and gasket and nothing else. I even called into my local Toyota dealership and asked about it and he has the bolts but they have no markers on them saying what size. I'm gonna pick one up tomorrow so I can find out the size and order them in SS. I'll set a reminder to ask what the part number he pulled up for them was though.

 

Ok, for anyone in the future that might need to find them.
90126-08037 Stud x 2 End two that go into engine block that get the two nuts
90179-08228 Nut x 2 End two that connect manifold to stud
91641-K0822 Bolt x 3 Middle three bolts directly into engine block to hold in manifold
91631-J0612 Bolts x 4 Manifold Heat Shield bolts
I'll try and find out sizes and post those up as well sometime in the next week. These are specific to 1NZ-FE engine. May work with others, don't know.

 

Here's a thread you may want to reference...looks like there is a new bolt that replaces the 90179-K0822 that has a tapered end and fewer threads.

DIY Header Install

I'm looking to see if I can find what the thread pitch is and I also saw these are used on other Toyota and Lexus models.

 

Alright here are the sizes of the OEM bolts/studs.
Manifold Studs: 38mm M8-1.25mm
Manifold Bolts: 21mm M8-1.25mm
Spring Bolt: 70mm M10-1.5mm
The nuts that were welded to my Weapon-R header were course threaded. Size of the stainless steel stud was a little different. Overall was the same but OEM had 10mm embed and 15mm sticking out. Stainless Steel had 12mm embed and 12 mm sticking out. I'm not going to link nuts, just because I ordered an assortment of them to see what I wanted. Look up 300 stainless steel nuts on Allenfasteners and you should be able to find what you want. The difference in the fine thread and course thread nut on the header confused me because I went through support where I ordered it and they explained Weapon-R stays true to OEM. However, I ordered two sets of bolts, one from Autozone in person and another online and both were fine threaded. Whatevs. I've not installed anything yet as I'm still waiting for the Spring Bolts. Maybe I'll take pictures once I'm done.

Links
Stainless Steel Studs: All Keywords: 300 stainless steel stud

Stainless Steel Bolts: All Keywords: stainless steel hex bolt

Spring Bolt: https://www.boltdepot.com/Hex_bolts_...steel_316.aspx

 

What is the spring bolt you are referring to...is that the bolt that holds the header and mid-pipe together? I find it odd that Toyota would use an SAE thread on that bolt, fine or coarse pitched, instead of a metric thread. Now Weapon-R using an SAE thread on that wouldn't surprise me too terribly much.

 

Yeah, the entire ordeal has me confused. I'm waiting for one last bolt and a correct donut gasket before I change everything out. So, I'll pull out the old Spring Bolt and measure it. The entire car is metric, but this one bolt is standard? Makes no sense. Also, yes, the spring bolt holds the cat to the header. Puts pressure on the donut gasket and allows for slight flex in the whole exhaust setup so it not too ridgid. Atleast, from my understanding.

 

That's the one I figured...I would almost guarantee the Toyota bolts for that are metric and Weapon-R might have used SAE nuts on the header itself.

Keep us posted.

 

Following.... What to see the final outcome

 

Alright. So, after talking and then thinking about it, I got metric bolts. Sure enough they fit perfectomundo. So, this weekend I'll put everything in, take some before and afters, and hopefully everything goes on without a hitch.

 

I know I said I'd get pics in last week, but I finished up Sunday and was in the mood to do nothing more than sit. So, I got everything in and even a CAI from Injen. Unfortunately, I broke a stud off in the engine block. Didn't want to do it the second time so I didn't pull the second one out. I got a screw extractor set but not sure if I even have the room the drill into the stud. the exhaust would rattle off the cross piece under the resonator. Took that off and now something else rattles in the back lol. Anyways, here are the pictures. Hopefully, they load.

 

Doing all that takes a lot of effort, well done.
I have heard (but never tried) that transmission fluid sometimes works as a penetrating oil to loosen up corroded bolts. Supposed to let it soak for 24 hours.
Sounds like there is not much room, but sometimes hitting the stud with a hammer can loosen up the corrosion. Just make sure you have 2 nuts jammed on the end and hit the nut not the stud thread

How do you like the Rhino ramps?
One of the other things I like to do is have a piece of old carpet down between the ramps - so much more comfortable
You can see it at the start of this video

 

Man honestly I ____ed up. I had a candle and torch and was just gonna let the heat soak the wax in. But the other 3 went so smooth I just went at it not even thinking. I've heard the transmission oil one. Usually I just spray pen oil on em and leave it overnight. I like the ramps but I wish they were a little taller. I can only back onto it because the front lip is too low.

 

Oh yea, it is backed on. Shows you how much attention I'm paying.
I know what you mean with the ramps. As an interim solution - to use my old steel ramps - I built some simple ramp cheaters.
Photobucket Link __________ Make sure your ad blocker is on and I hate they way they shuffle the picture order - gave up with them

In the end my son bought a Mazda CX5 and the tires were just too wide for the old steel ramps.
My son-in-law bought a Prius and that has a huge hinged plastic panel hiding the engine, which wouldn't open using regular ramps. Needed something taller.
I looked at the Rhino ramps and decided to build my own to meet the new width and height needs. Cost more, but works nicely
In fact there is too much room!! Had to build up a furniture dolly from Harbor F to put the oil drain pan on, otherwise the oil splashes too much when draining

No more Photobucket