Demon bolts

Red_Z

Just got my Z and has 100 miles on it. I know I will replace the cat with tp or hfc eventually. Do you think is a good idea to start removing the bolts and replace it with normal bolts while is still new?

Kevin@RAD

Chances are they're already stuck on. You'll have to break them regardless.

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370ZilverZ

I did mine at 250 miles with no issues at all. Invest in a set of Grip-tite sockets and a good sized breaker bar for leverage and spray the bolts good with WD-40 or PB Blaster.

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BMW Z4

370Z Purist

There are some damned good bolt breakers out there. I've seen decent results with PB Blaster and WD40. I say that because a friend of mine has this other can which made both the products look terrible.

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-Phil

"Since one of my brake light bulbs just went out, the forum told me that my piston rings are about to blow."

vividracing

Please find out the name of that product!

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370Z Purist

Did a little penetrating spray search on the internet, while practicing my Google-Fu.

Turns out it's Liquid Wrench. Seemed to work better than either PB Blaster or WD40 (which is terrible for breaking bolts in general, if you ask me). If you can find PB Blaster or Liquid Wrench or WD40, choose either of the two over WD40.

I also found a forum post that quoted a magazine, which showed an interesting result:

Best Penetrating Oil Test - Surprise Winner

For those of you who are TL;DR:

A 1:1 ratio mix of automatic tranny fluid and acetone was shown to make breaking the bolt much easier; only a tenth of the torque was needed to break the bolt.

Also if you're strapped for penetrating oil (say, if you're like my friend and I, and need more penetrating oil but it's 3 am and the local walmart/major-retail-chain-open-24-hrs is sold out for some odd reason), highly carbonated drinks also work. Not nearly as well as WD40, but much better than nothing else. Vinegar also works, although it's kind of a waste.

There's also that new fangled naturally based (soy) lubricants which are apparently just as effective/more effective while being environmentally friendly. The best part is that they don't smell like nerve gas.

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-Phil

"Since one of my brake light bulbs just went out, the forum told me that my piston rings are about to blow."

vjarnot

Judging by my advanced sense of smell with regard to hydrocarbons, Liquid Wrench is just Kroil repackaged... and Kroil penetrates better than Ron Jeremy ever did, so I'm not surprised it fared well.

Nice find on the ATF mix. Although I don't know why they chose acetone to thin it, that stuff evaporates too damn quick... mineral spirits (paint thinner) would've been a more practical choice IMHO.

370Z Purist

I'm sure you'd know just how well Ron Jeremy penetrates!

Well, the faster it evaporates, the faster you can start turning on the bolt. I guess you would have to be pretty generous and try to use a piston oiler or similar to try to get a direct stream onto the bolt. This is, of course, given you don't splash any on yourself. I once saw a demonstration of a styrofoam head being placed into acetone.

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-Phil

"Since one of my brake light bulbs just went out, the forum told me that my piston rings are about to blow."

vjarnot

Acetone is one of the safer industrial solvents, no issues with getting it on your skin. The other problem with acetone, though, is that it eats certain plastics...

gomer_110

This is not totally accurate. I work with the stuff for my job and i can tell you that excessive amounts of contact with the skin can make you sick. Small amounts aren't gonna hurt you but continue splashing it on yourself and you're gonna get sick.

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'17 Titan Bone Stock

370Z Purist

I'm not sure on what concentration of acetone was used for the penetrant mix. I'd imagine with a percentage high enough, you'd make it difficult to use unless you were in a very well ventilated area.

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-Phil

"Since one of my brake light bulbs just went out, the forum told me that my piston rings are about to blow."

TopElement

When the time comes to remove stock cats, just be prepared to snap off the demon bolts with a good 14mm bolt remover.
Work on those first, and the rest of the install is a walk in the park.

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Viera

Just out of curiosity.. does anyone know what the demon bolts are torqued at from the factory?

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harman.khinda

I'm installing test pipes they didn't come with any hardware. Anybody know what nuts belts and washes I need? Like what length, width and grade?

370Z Purist

Your test pipes will need the Y pipe gasket and the exhaust collector gasket, as well as nuts and bolts. What brand are your test pipes? I'm guessing you did a private buy because if you paid retail (i.e. bought new) for TPs without hardware, you were ripped off.

Stock cats are known to be insane to remove. If you have an open faced ratchet, you might find better results. I remember reading Bonnani's DIY and seeing him snake some ridiculous frankentool through the engine bay to break one of the bolts. They're probably torqued to a spec of "innumerable hellfires" pounds per foot. The fact that they're constantly heated and cooled, as well as exposed to dirt, water, moisture, salts, (road salts during the winter if you're unlucky), plus general wear and tear means they're probably in excess of 500 pounds per foot once they've completely rusted over to the point where the nut and bolt have become one with the cat and gasket. From the factory? It's probably a spec of maybe 30, although impact guns used with negligence means more like 60.

I'd probably just soak the bolts in a good amount of penetrant and let it sit for an hour or so. Just remember to let the car cool, and also to not start up the car afterwards.

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-Phil

"Since one of my brake light bulbs just went out, the forum told me that my piston rings are about to blow."