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exhaust - do I need the flexi?
craigdiver - 7/8/18 at 03:30 PM

As per the title, do I need the flexi or are the exhaust mounting rubbers sufficient?

nick205 - 7/8/18 at 03:37 PM

No flexi on my MK Indy, just a rubber mount at the rear of the silencer. Never had any issues with it.

craigdiver - 7/8/18 at 03:42 PM

quote:
Originally posted by nick205
No flexi on my MK Indy, just a rubber mount at the rear of the silencer. Never had any issues with it.


Thanks Nick, was going to support near the cat then at the rear of the silencer but you have got me thinking now if two mounts
are needed, hmmmm

rusty nuts - 7/8/18 at 03:52 PM

Mine has just a single mount at the rear , have had no problems in at least 12 years . Make sure the engine mounts don't have too much flex , fit an engine steady if needed.

myke pocock - 7/8/18 at 03:59 PM

Well that IS a surprise. I would have thought flexi all day but just goes to show what I know!!! (or dont)

nick205 - 7/8/18 at 04:09 PM

quote:
Originally posted by craigdiver
quote:
Originally posted by nick205
No flexi on my MK Indy, just a rubber mount at the rear of the silencer. Never had any issues with it.


Thanks Nick, was going to support near the cat then at the rear of the silencer but you have got me thinking now if two mounts
are needed, hmmmm



I must admit that my exhaust didn't have (or need) a cat in it.

snapper - 7/8/18 at 05:57 PM

It’s all about engine movement so you need firm engine mounts as stated and possibly an engine steady but I’ve not needed one.
Counter intuitively a single slightly flexible exhaust mount near the back of the silencer is better than 2 mounts as the forward mount becomes the point at which the manifold and down-pipe will pivot, then you would need a flexi

Nickp - 8/8/18 at 05:37 AM

No flexi on mine either, just a single rubber mount under the silencer. I have Land Rover engine mounts and a steady.
My silencer looks a fair bit bigger than yours (27" IIRC) and was still just under the noise limit at IVA.
Also, what's your plans for that CAT? As there's a lot of sharp edges on it.

[Edited on 8/8/18 by Nickp]

craigdiver - 8/8/18 at 11:43 AM

quote:
Originally posted by Nickp
No flexi on mine either, just a single rubber mount under the silencer. I have Land Rover engine mounts and a steady.
My silencer looks a fair bit bigger than yours (27" IIRC) and was still just under the noise limit at IVA.
Also, what's your plans for that CAT? As there's a lot of sharp edges on it.

[Edited on 8/8/18 by Nickp]


Silencer was cheap, was hoping I would have room for a second that could be put in line to reduce db if needed. The cat will be wrapped in exhaust wrap to keep it nice and hot (and cover the sharp edges). (going to round off some of the sharp edges too)

[Edited on 8/8/18 by craigdiver]

loggyboy - 8/8/18 at 01:08 PM

Depend son how firm the engine is and if the exhaust isnt solidly mounted to the chassis.

If you have a very firm engine it shouldnt be needed, if there is engine movement you want to match that with exhaust, either with the flexi or have a reasonable movement in which ever rubbers you mount the exhaust it on.