The Bolt size for the catalytic converter should be between m10 and m25x25. They should measure approximately 25mm in length. The bolt should have a thread pitch of 12-14mm X 1.5M (metric). The nut should be m10x1.25 and must be self-locking as an exhaust nut.
You can use standard-sized bolts, but you should try to get bolts of class 10.9 strength. And the length is approximately 1.25 inches. If you don’t have a flanged head, the bolts will need to be flanged. Otherwise, washers will be required, and a longer bolt may be necessary.
Avoid nyloc lock nuts. Split washers can be used to prevent the nuts from backing out. The bolts should be 14mm, but due to so much rust, they end up being 15.2845mm. They do need to be torched.

Typical Bolt Size for Connecting Mid-Pipe to the Catalytic Converter
The typical bolt size for connecting mid-pipe to catalytic converter is 10mmx1.25, judging from your 14mm head. These numbers are not guaranteed, but they’re a good starting point. The factory hardware measures 14mm head at each end, with either 17mm or14mm at the manifold.
There is a significant likelihood that the factory fasteners were changed if the exhaust had been removed. Any US source will usually be 14mm or 15, and the rear can be any size since it’s just a nut and bolt.
Read Also: How to Remove Catalytic Converter Bolts?
Bolt Size for 350z Catalytic Converter
Bolt size for 350z catalytic converter is 40-50mm length and 14mm heads; thread diameter 7. Metric M10 1.25mm thread pitch. The overall length of the Catalytic Converter: is 20″.
350z catalytic converter is the best choice if you are looking to replace your damaged or failed catalytic converter. This catalytic converter was made specifically for your vehicle and is an excellent alternative to dealers at a fair price. The 350z catalytic converter is made according to OEM specifications, so it’s easy to install.
Read Also: Do Headers Replace Catalytic Converter?
Bolt Size for 370z Catalytic Converter
The bolt size of the 370z catalytic converter is Length (mm). 8mm * 12mm ; Length (in). 3/4 Inch * 1 Inch; Thread Size. 1/2-13 Inches.
For durability and long-lasting life, the 370z catalytic converter is made from top-quality materials. This product is designed to be used in ball and socket joints.
The Y pipe then transitions to 3″ stainless steel piping from the velocity merge to the rear 3” exhaust flange. For increased strength and rigidity, the Y pipe has an integrated dimpled-gusset plate that ties together the individual runners.
Bolt Size for g37 Catalytic Converter
G37 2008 Catalytic Inlet Diameter 2.25″. M10x1.5 thread. Install a catalytic outlet diameter of 2.25 inches to get your car through the smog test. The factory device will be replaced by this converter, which is a component of the exhaust header assembly, with little to no fabrication.
To remove the air-pressure sensor socket, you’ll need either a 7/8″ or 22mm oxygen sensor socket. The oxygen sensors are expensive at $160.00 from an Infiniti dealer, so make sure you don’t damage them.
Bolt Size for g35 Catalytic Converter
Gaskets are included free of charge with every purchase. Infiniti G35 2008 Catalytic Outlet Diameter is 2.25″.
This item fits all G35 sedan models that have a 3.5L V6 engine. The unit is designed to be easily swapped with the OEM unit and ensures a perfect fit. Proper precious metal loading and OBDII-configured catalyst technology assure proper performance emissions without any early check engine lights.
Install a replacement converter if your car is in need of it. This converter, which is a component of the exhaust manifold assembly, may easily replace the original unit without any fabrication.
Miata Catalytic Converter Bolt Size
Miata catalytic converter bolt size; Length (mm). 8mm * 12mm ; Length (in). 3/4 Inch * 1 Inch; Thread Size. 1/2-13 Inches. You will need two m10 bolts & nuts.M10 bolts for an mx5 have a fine pitch (12.5) and a 14mm head.
Bolts from elsewhere will have a 17mm head on an M10 shank. If you need to replace a nut or bolt, any m10 bolts are sufficient. However, the studs for the cat are m10x1.25.
2002 Nissan Quest Catalytic Converter Bolt Size
The bolt size of the 2002 Nissan Quest catalytic converter is 14mm wrench, and the thread diameter is 10.
The 2002 Nissan Altima could be your best car. You might just have trouble keeping it highway-approved. Advance Auto Parts can provide the Catalytic Converter product that you need, no matter what your situation.
Honda Accord Catalytic Converter Bolt Size
Honda accord catalytic converter bolts are m10-1.25×25. The length of the bolts is m10-1.25×25.
For nuts and bolts, don’t shop at an auto parts store. Get stainless steel bolts in class 10.9 strength. If you purchase them in stainless steel, they will last a lot longer than the OEM bolts.
For 3 high-quality stainless steel bolts, you can expect to spend about $10 at a hardware shop. You must have self-locking nuts. You can also find the original Honda stuff here: bolt, nut.
FAQ
Can You Bolt on a Catalytic Converter?
Yes, you can bolt on a catalytic converter. It also depends on catalytic converter weight. The modern gasoline engine’s catalytic converter is one of the essential components for reducing emissions. It is a crucial component of the exhaust system and ensures that the vehicle’s hydrocarbon emissions are kept within reasonable bounds.
Here are a few steps to bolt on a catalytic converter:
- Step 1: Lift the car and place the jack stands under it.
- Step 2: Track down the catalytic converter.
- Step 3: Eliminate all oxygen sensors.
- Step 4: Use penetrating oil to spray.
- Step 5: Get your tools ready.
- Step 6: Catalytic converter replacement.
- Step 7: Put the catalytic converter in place.