my exhaust manifold mk5 2.0GLS

[C0RKTINA 104]

I have had trouble keeping the exhaust clamped on tight and when i went to tighten it today the downpipe slipped striaght through the clamp. Motomobil give the internal diamet of the clamp as 47 mm whereas mine is 50mm or so, presumably it's the wrong clamp. the manifold is shaped to take the tulip endof the downpipe, should there be a sealing ring in there? possibly not with the shaped manifold?  

the two studs on the manifold are different to each other, does that matter? 

[sheffieldcortinacentre 726]

Theres two types, originally cortinas had a separate ring & both the manifold & pipe were recessed, later versions had the ring cast into the manifold so only the pipe was bell shaped, the studs are the same with 17mm nuts & lock washers.

Sometimes it can help to tweak the downpipe flange to be more belled out as they're not as well made.

[C0RKTINA 104]

thanks Craig....the bell end will slip stright through the clamp so I think it needs more than tweaking.

 

 I have an old ring , maybe if i put the pipe in the vice upright and beat down on the ring it would open a bit.

I'm amazed it stayed on at all... must have been nipped up behind the clamp.

 

i shall have to either get a new down pipe or a new clamp. decisions decsions. i suppose the clamp is cheaper by far so I should go that way forst I guess.

 

I did notice the other day that the mk4 1.6 and mk5 2.0 are radically different from each other in the route they take , maybe that has a bearing...

Edited November 3, 2025 by norton

[sheffieldcortinacentre 726]

Never took much notice thought they were same ,I thought ohv were slightly smaller ( I know the fwd ones are a different size.

[C0RKTINA 104]

im going to buy both new and be done with it. may be able to use the replaced bits elsewhere one day 

[C0RKTINA 104]

postscript .  the flange Motomobil sell is too small for the 2 litre downpipe. ( 47mm vs 50mm....my flange is 50mm ) im assuming then that my pipe is incorrect, possbly a 1.6 unit. my exisiting flange should fit it i hope.   (potentially i might have to buy the middle and back sections too....)  

[C0RKTINA 104]

just to round it off...the new pipe from Motomobil fitted striaght on and is a much better job than the one that was on it, presumably a 1.6 pipe.... heavier gauge metal too.