Cat to Downpipe Bolt size

[AJC]

Anyone know the size of the bolts that attaches the downpipe to the primary cat, and what sort of rough cost would it be to have the broken/fuzed bolts drilled out and re tapped/helicoiled?

 

[Belly93]

Is that the ones with the springs on?

 

[AJC]

It is indeed

 

[Belly93]

Is it snapped flush with were it bolts to or does it still have part of the bolt sticking out

 

[frank]

sometimes 14mm, and sometimes 17mm iirc, and on the ones that i,ve snapped i welded a nut onto the stump, and then the stump screwed out with ease.
they would be a mission to drill out !

 

[Belly93]

When I snapped mine I wheny to mates garage and he heated it up with an oxy acetalene torch and it wound straight out

 

[AJC]

Oh these are far far beyond having a nut welded on, these have completely fuzed to the cat flange and one of them is a very distorted stump, so i guess if i have them drilled to a 14mm bolt that should suffice. I wont be doing the drilling, i work next door to an engineering firm that make armor for military applications amongst other things and are used to working with tough materials

 

[Belly93]

If there's still a stump of the bolt if you can get it hot enough it should just wind out

 

[frank]

If there's still a stump of the bolt if you can get it hot enough it should just wind out

+1, most the ones that i,ve done have been a concretion that barely resembled a bolt

 

[AJC]

even like these?

 

[frank]

the one on the left no probs, but the other side and the lower sealing ring are beyond repair ! best find a better one in the scrappies imo

 

[Belly93]

One was like that :/ so I've ended up with a preface cat as I couldn't afford and it was free

 

[AJC]

well it only cost me a tenner plus delivery, and the mani it is attached to is in pretty good nick, so i could sell that to cover the cost of CG cat i guess, anyone got one cheap?

 

[SuluR]

Glad to see you recieved the cat, not glad that it's causing you trouble!

 

[AJC]

No worries mate, was hoping to be able to save it, but looks like its done for, one of those things. I still got the mani that can be sold, that will cover what i paid ya for it tho, so not all bad, just hoping my cat bolts are in better nick and i dont snap them when i put on my peter lloyd system tomoz