Flexible Exhaust Joints

[Guest Gargoil]

Has anyone had experience with the above?

Since the new silencer was fitted and a different mounting system used,

there isn't much movement of the exhaust in relationship with the bodywork.

In fact it all seems to be clamped down quite tightly.

So, looking at flexible couplings just to give that bit of movement between manifold and the rest of the system.

Looks like a job I can do myself too, which is a plus......

[GambolGold]

Yes! My exhaust manifold would self-distruct by cracking due to vibration, particularly at tick-over. I strengthened it, yet it broke again - it just took longer the second time. I added a ball and socket type of exhaust connector and this seems to be a permanent fix, dampening the vibration.

 

Edited November 3, 2014 by GambolGold

[fry61]

Got a basket-weave flexi-joint fitted after the s/steel tube fractured just in front of the silencer.

[Guest Gargoil]

Great, do they compress or should they be put under tension in any way?

The one I am thinking of fitting is only going to be a short one due to available space, so wondering about the best way of using it.

[fry61]

The joint fitted to Florin's s/steel pipe-work is approx. 4" long including the welded sleeves & was installed as is -- no stretch or compression.

[Guest Tim Norman]

They can be very restrictive though.

[Snapperpaul]

Your engine mounts must be weak

I've run a solid system on an S3 since it was built only fitted at the manifold and with 1 bobbin rear of the can

[speedtripledan]

The silencer mount to the body should have enough flex, as Paul said maybe your engine mounts are weak. Never had any issues of that kind on all my kits

Edited November 4, 2014 by DanE

[tractor]

as dan and paul my engine moves very little so rigid pipe with bobbin on silencer and no probs

[fry61]

They can be very restrictive though.

 

The flexi-joint fitted on Florin is same bore through-out, silencer is much bigger than "standard" to bring the db level down to low 90's.

 

So maybe weight of system was the cause of crack ? Box is now supported on bobbins front & back.

[Guest mower man]

I had manifold cracking issues on my s7 especialy when I fitted a big repackable silencer , this was cured by a flexi joint after the manifold /before the silencer and also a second mount at the front of the silencer the joint was the same internal dia as the front pipe /silencer no restiction and it completely cured the prob , stiff engine mounts in my op would cause the pipe to whip ven more on one bobbin ,the twin mounts I had also tried to place the bobbins in compression not shear or tension ,they still degrade with heat but last far longer mowerman

[Guest Gargoil]

Must admit I hadn't thought of checking the engine mounts. Had assumed that there would naturally be some movement from the engine, but perhaps there is more than desirable. Either way, I will look for any cracks or perishing to the rubber, thanks for the advice.

Still going to use a flexible joint though, as an aid to reducing any vibration from the engine and just in case.....manifolds don't grow on trees.