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Exhaust bracket - best way to mount silencer?
Sloan85 - 9/8/13 at 08:54 PM

Not sure of the best way to mount the exhaust bracket for the silencer. I will be using a small rubber bobbin but the the three ways I can see are......



Straight through the GRP side panel - the back of the panel could be strengthened by sikaflexing a 100mm aluminium square to it and drilling through that.

Fabricate a bracket so the fixing goes through the side panel into one of the diagonal tubes for added strength (At present, the bracket on the silencer doesnt line up with the diagonal bracing)

Fabricate a bracket that fixes to the underneath of the car




Any suggestions? As usual, photos would be helpful and much appreciated.

Cheers




paulf - 9/8/13 at 08:59 PM

When I first built my car I used a bobbin through the side panel, however this means that the rubber part is in shear and it kept breaking.I then made a bracket mounting under the floor so as the weight of the exhaust sat onto the rubber mount and it has never been a problem since.
Paul

Sloan85 - 9/8/13 at 09:03 PM

Hadn't thought about the loadings on the bobbin. I guess the rubber is just stuck to the metal so sheer will pull it apart. Ill see what I can do to mount the bobbin horizontally.

Thanks

Daddylonglegs - 9/8/13 at 09:29 PM

I fitted my R1 can using a 2mm plate secured tot eh underside of the side rail using an M6 rivnut and bolt. The bobbin was then bolted throught the plate and through the exhaust clamp.

Because the bobbin sits vertical, the only load is sideways (same as Paul's), so much less chance of shearing issues. It's been fine so far.

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HTH

[Edited on 9/8/13 by Daddylonglegs]

sky12042 - 9/8/13 at 09:43 PM

Was thinking the same the other day and ordered this of the bay. Maybe of some use.

http://www.ebay.co.uk/itm/NISSAN-Terrano-II-Exhaust-Rubber-Mounting-/290580327978

Andy.

nick205 - 9/8/13 at 09:57 PM

Same as Paul and Daddylonglegs on my Indy.

Worth printing out though that the standard MK silencer mount has two shortcomings...

1. It's mounted off the end cap and not the silencer can itself which places stress on the rivets holding the end cap onto the can, these quickly wore loose and rattled on mine. I replaced them with bigger stainless rivets which held for longer, but still failed.

2. The standard MK support tab is also prone to cracking and failing. I braced mine either side to over come this.

Note: this was MK supplied parts in 2005, no idea if current parts are the same design.

Check my website www.winchester7.com for pictures of what I did.

Sloan85 - 9/8/13 at 11:03 PM

The end section is fixed to the main section by 4no. m6 stainless bolts so should be nice and secure.

Some good ideas there. Hopefully I'll be able to sort something coming from the bottom of the side chassis rail.

Cheers

whitestu - 10/8/13 at 07:21 AM

After messing about with alloy and steel brackets mounted to the bottom rail I ended up bolting a thickish (5mm) piece of steel to the floor and sitting the silencer bobbin on this.

Dick Axtell - 10/8/13 at 08:34 AM

quote:
Originally posted by paulf
When I first built my car I used a bobbin through the side panel, however this means that the rubber part is in shear and it kept breaking.I then made a bracket mounting under the floor so as the weight of the exhaust sat onto the rubber mount and it has never been a problem since.

Excellent point here, gentlemen! And thanks for the illustrations. This looks like a very useful mod, as my exhaust can is also mounted with the bobbin in shear, (axis horizontal). Compression should help it to last longer.

Nick205 - Noted your comments. Will definitely check that out. Probably have to add another support nearer front of can.

nick205 - 15/8/13 at 09:22 PM

Thought these pics might be useful...

1. Modified MK silencer with additional bracing on the support tab.


2. Chassis mounted vertical support bobbin (a right angle bracket was fabricated to attach the silencer to the top of the bobbin).