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Truenotch

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I see a lot of L series with twin 2" and resonators going into a 2 in 2 out muffler.
Z headers will fit with a bit of modification to clear the steering centre link, sidedraughts add to the aural symphony
I was keen on a twin setup but couldn't be bothered and stuck with headers, a single 2" and a muffler on the end, sounds crappy at idle but I do enjoy the sound of it when the throttles slam shut then go wide open on a high rpm gearshift

 

 

Get some 3 inch in ya

 

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Get a set of headers and run two 2" pipes side by side with a resonator or small muffler on the centre of each pipe then have them share a twin in and out muffler at the rear with about 6" of straight after it.

Basically though, put anything on it and it will sound like a Z. Changing the intake to twin or triple carbs will give you better noises again. Even if you only increased the pipe size slightly and still ran stock exhaust manifold you'd get the sound you're after. Hell, even changing the mufflers would get the sound. It's the same motor after all.

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  • 10 months later...

WOF man said the old muffler wouldn't pass next time, so before next time with the help of a certain 2-post-lift-owning member's garage, I replaced approximately 1/3 of my Stagea exhaust with 3" straight through pipe/muffler. Gave it a start up, and a free rev to WOT a few times with just the new 3" straight through muffler, no pipe after, no main muffler and it didn't sound too loud even like that. With the rear muffler reinstalled it was back to near silent stock setup, but ready for two more exhaust upgrades and the new engine and manual trans setup. I wasted a few bucks on preformed cones to lead out of the stock post-cat pipe into the front kiwi made 3" vband flange, and the same at the back from the rear vband into the stock pipe pre rear muffler. Pics:

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What I definitely wasn't going to do was spend cash on replacing the muffler with one the same size, ie, no work torwards something that wasn't the end goal for the car (600hp @ crank), so the only logical thing to do was make the exhaust modular by vband flanges so I can do the rear half next (and keep the stocker for civilised usage if desired) and the front half when I drop the built engine in. Car definitely isn't OS so no body work shots, but the exhaust build for it was discussed on some prior pages, hence update. I'll probably put a coby or similar where the cat currently lives when I do the front half for maximum muffle and smoothness. Until next time, adios.

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Truth re warping! Definitely take special care to not do that. But even with these Chinesium clamps properly torqued there is no way in hell they are going to overcome friction and rotate even with the mufflers hanging from one side worst case, let alone with a properly supported/mounted exhaust. Drill and dowel if you really want precision alignment.

As for road rash, if you have 3cm of clearance, I guess so as you could use a 2 bolt an keep the bottom pretty close to straight pipe, but for anything more reasonable and nur-spec happy (low cars suck there, and any real road) there's ample room to keep them out of the way of harm. Meh. You could always put a ramp in front of them which you'd have to do with a normal flange anyway if you wanted it to survive being dragged over stuff.

How's the FE3? On hold for 2 odd years since someone posted 2 threads on drag day and I asked a stack of questions in the wrong one that were answered in the other one and everyone got their nipples in a twist. I prefer my nipples straight, erect, and female, so gave the entire shooting match a miss for quite some time. Was watching some vids of it the other night, though, and had a yearning to feel the thrust in the back again. Have to resurrect it at some point, it's too good not to - will be even better with latest code, too! :-)

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  • 1 month later...

Hey guys,

So the exhaust on my Diamante is absolutely had it (front down pipe is smashed, rear section is rusting away etc) so I need to replace the exhaust sooner than later. Given that I'm planning an engine swap, I want to make sure the exhaust would be suitable and ready. I'm thinking a mild steel 3" mandrel bent system with one or two hotdog resonators and a muffler that is reasonably quiet at the rear, but with a servo actuated bypass valve before the rear muffler - kind of similar to how the 'Active Exhaust' works on the GTO and some later Galants and Diamantes. The factory GTO appears to just have a cat converter up front, no mufflers in the middle and a restrictive muffler in the rear that then splits to each side, but there is a valve just in front of the rear muffler that basically allows the exhaust to just bypass the rear muffler and exit out of one of the exhaust pipes. I'm hoping to replicate this, but am wary of the system being too loud or raspy when in 'quiet' mode.

What would be the ideal length of resonators to use? Does anyone have recommendations of a good 3" rear muffler? Ideally an oval type with center in and offset out.

Below is a pic of the stock GTO exhaust systems - on the left is the N/A one which is similar to the Diamante system, while on the right is the TT version:

stealth-install-vr4-exhaust-04.jpg

 

Thanks!

 

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If it was mine I would go 2 1/2 inch mandrel Bent, single 18 inch reso, and something like a flowmaster fx. 3 inch on a non turbo 3 litre is probably just making life difficult for minimal gains. 

Years ago I replaced the rear muffler on my 30m Diamante and ditched the flapper bypass system, it made enough noise with the front section standard.

I actually purchased a somewhat expensive coby muffler from coby in hamilton recently for my honda, pretty happy with the build quality and sound. If you don’t mind paying a bit more to support a local company.

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Aah yes well anything that passes the tennis ball test will be fine for a turbo car. Do all you can do to keep dump pipe size as big as possible out of the turbo(s) to help with spool.

You won't need much to quieten it down, one thing that seems to reduce drone is a reasonable length of tip after the rear muffler  ( say 300mm will make a dramatic reduction  compared to 75mm of the same pipe diameter from what I have found). 

Also twin tips of maybe 2 1/4 reduces drone compared to single 3 inch tip.

 

 

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Quick question. I've changed my exhaust on my 1300 escort from standard manifold and one muffler, to 4--2-1 extractors and one slightly smaller muffler (original escort muffler). All the same length standard pipe  (1 3/4?) It now has an annoying droning sound, especially at low speed (Road noise probably drowns it out after 60km). Would something like a coby resonator after the axle fix this? I'm not after a performance system, just something a little more discreet. Cheers

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1 hour ago, bmxnz11 said:

Quick question. I've changed my exhaust on my 1300 escort from standard manifold and one muffler, to 4--2-1 extractors and one slightly smaller muffler (original escort muffler). All the same length standard pipe  (1 3/4?) It now has an annoying droning sound, especially at low speed (Road noise probably drowns it out after 60km). Would something like a coby resonator after the axle fix this? I'm not after a performance system, just something a little more discreet. Cheers

Yes

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When building an exhaust, how much clearance would be suitable from a floor pan? Most of floor has fabric sound deadening on top side. Want to tuck it up as high as I can without needing heat shielding. Is 20mm fine? If shielding is a good idea, what do people use? How much movement would one expect from a FR chassis exhaust? All of the questions. Stock 1500cc engine with 38mm tube.

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If it's turbo that might be a bit close for comfort

For shielding you can just do a piece of panel steel folded up to provide an air gap. Insulate where it mounts with some rubber or cork gasket and you are laughing.

 

Morris minors have a folded up box packed with asbestos 

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Nah not turbo, just a typical 80's econobox engine. Folding up steel could work, just a bit of work due to space / angles, so wondering what the norm is. There were a few bits on the factory exhaust, but i've cut the cat out and replaced it with a longer section of pipe as there was a gap from cat to engine pipe to start with. So putting on a longer bit of pipe and removing cat seemed like a good plan.

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