djmanu

iTrader: (2)

I am in process of putting my OEM Jpipe and 3rd cat back on. I want to put some stainless steel bolts on it this time because i want to prevent them from rusting on. I am not too sure what type and size bolts I need. Any info would be greatly appreciated!

94eg!

The 3rd cat has studs pressed into the flanges. That means there are only nuts that you can repalce w/ stainless. There are no threaded holes for "bolts".




The front & rear cat use threaded studs that screw into the flanges. The studs are 10x24mm, but I'm not sure of the thread pitch (maybe 1.25mm). You will need to subtract the bolt head length from the 24mm if you plan on making the switch. Typically these studs are very difficult to remove, which is why OEM doesn't use bolts. The nuts are much more likely to come off over the years vs a bolt due to the extreme heat cycling in this area. Who knows....it may just work. But you won't know till you try and remove them years later.

KN_TL

iTrader: (3)

I tried stainless on a custom setup. 2 out of the 6 galled on me and I ended up cutting them off. I am switching to grade 8.

djmanu

iTrader: (2)

I got the bolts removed though from a shop that just hammered them out. the OEM ones are expensive and arent stainless. I saw somewhere that people changed them to stainless but not sure what kind i need. the shop told me to get grade 10

gwiffer

iTrader: (7)

I'm going to do the same thing.

I was just going to go to the hardware store and use 10mm SS bolts/nuts and a liberal amount of copper anti-seize.

I guess KN is saying that the lower grade bolts will gall because of the heat cycling that occurs in the exhaust. I'll probably use the higher grade 8.8, 9.8, or 10.9 bolts. I'll have to find out what my local store sells.

Richie v6

We used to include stainless hardware with our products. They would seize and strip easily. The worst part was that if you didn't seize them on they would start to self loosen from all the heating and cooling cycles.

94eg!

When it comes to metric hardware, the scale is different. Grade 10.9 is the minimum for auto use. Grade 8 metric (really grade 8.8) hardware is sub-par like SAE grade 5.

KN_TL

iTrader: (3)

Metric nuts and bolts are too hard to find up here so I am using standard grade 8. Should be plenty strong enough to keep the exhaust together.......

powerflow

At my work we use a lot of fasteners for pressure products. ASTM/SAE type. Mostly A-194 B7 which is an alloy steel with high tensile strength, but will surface corrode. For 316 SST, there is multiple class. Class II B8M 316 SST has a higher tensile strength than class I B8M 316 SST. Fastenal is good source for specific fasteners.