Custom exhaust - silencer placement?
Discussion
I'm currently building a 3.9 V8 Defender and I'm at the stage of needing to construct the exhaust. I can't drive it as-is and I haven't currently got anything I can trailer it with so I'm going to DIY using Jetex parts.
The headers run into the cats and then into a single pipe just behind the gearbox. I don't want to over-silence it (after all, what's a V8 for?
) so the plan is to use just one silencer. I believe I can position this either immediately after the header becomes a single outlet, or alternatively at the back of the car just before the end of the exhaust.
Question is, is there any benefit (or any type) in either option?
TIA.
The headers run into the cats and then into a single pipe just behind the gearbox. I don't want to over-silence it (after all, what's a V8 for?
) so the plan is to use just one silencer. I believe I can position this either immediately after the header becomes a single outlet, or alternatively at the back of the car just before the end of the exhaust.Question is, is there any benefit (or any type) in either option?
TIA.
Right at the back is always best!
(for various complex reasons)
In a defender there isn't a lot of room behind the rear axle for a decent sized back box, which is why the factory runs with a centre box as well to get overal noise levels down. As mentioned by others, i have no idea why you'd DIY this these days? Just buy one of the many, well, well, well proven aftermarket systems for V8 LRs and be done with it!
(for various complex reasons)
In a defender there isn't a lot of room behind the rear axle for a decent sized back box, which is why the factory runs with a centre box as well to get overal noise levels down. As mentioned by others, i have no idea why you'd DIY this these days? Just buy one of the many, well, well, well proven aftermarket systems for V8 LRs and be done with it!
As far as I know there isn’t an off the shelf option for a 3.9i Defender? 3.5 yes, that’s what it was running before, but that’s a much smaller diameter and a different fitting at the back of the headers. The (ex Discovery) headers are something like 2.75 inches; I’m not in front of it currently so can’t re-measure. I’ve got the old Discovery exhaust but it’s nowhere near a fit as it has another 10” length in it plus it exits at the rear not the side.
If someone can point me at the one I need I’m all ears!
If someone can point me at the one I need I’m all ears!
On my 100" Bowler I have a Jetex oval silencer just after the y piece and a circular one just before the outlet, pm me and I'll email you photos of the installation. Also guide dimensions between the components.
All 2.5"Jetex parts to the y piece.
Stainless after centre silencer to the outlet.
Subtle rumble until you get to 3000 rpm, easy to live with all day.
All 2.5"Jetex parts to the y piece.
Stainless after centre silencer to the outlet.
Subtle rumble until you get to 3000 rpm, easy to live with all day.
Edited by 100SRV on Sunday 15th September 12:42
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