Recommend me a muffler.

[Dougal]

At some stage in the foreseeable future, I'll be putting a new muffler on the rangie.

Currently it's a 2 1/4" system with a large oval chambered muffler, in and out and offset to different sides.
There's a flange upstream of the muffer, I'll get everything from this point back replaced with 2.5". I need to keep a 2 1/4" downpipe for now, that may change if I find a way to make a 2.5" fit and not touch anything.

So what's a good muffler that won't have noise patrol after me but will still flow better than what I've got.
I have plans for more boost, hence the upgrade.

[rovercare]

Why keep such little pipe?

3" Mandrel all the way:D

[1103.9TDI]

rovercare Why keep such little pipe?

3" Mandrel all the way

....What he said......and leave out the muffler, mine's straight through, haven't had a problem with noise, in fact I haven't had any problems overall:).

[Dougal]

3" would create extra clearance problems, no muffler isn't road-legal.

[rovercare]

3" would create extra clearance problems, no muffler isn't road-legal.

Mine's 3":p

[Dougal]

Mine's 3":p

I have a completely different engine mount and space between that and the AC compressor isn't as big as I'd like it to be.
No I'm not jealous.;) Muffler choice has a far bigger impact on backpressure than going from 2.5-3" pipe.

[rovercare]

I have a completely different engine mount and space between that and the AC compressor isn't as big as I'd like it to be.
No I'm not jealous.;) Muffler choice has a far bigger impact on backpressure than going from 2.5-3" pipe.

But with the right muffler AND 3" pipe, it would be better, yea?:D

[Dougal]

But with the right muffler AND 3" pipe, it would be better, yea?:D

No, just noisier.:D

[Dougal]

Some rough calcs put the difference in pumping power between 2.5 and 3" at about 3kw.

That's 30psi boost, 3000rpm with EGT's of 750 deg C preturbo and 620 deg C post-turbo.
Also done at 100% VE, probably only really 70% at that rpm.

Theoretical engine power in those conditions (BSFC of 250g/kwh and AFR of 22:1) is 235kw.
I'm only aiming for 2/3 of that so I think I'll be fine with a 2.5. The only current issue is finding a suitable muffler.

[isuzurover]

IMHO - one of those glass-fibre-filled almost straight through mufflers would be a good option. Hope that makes sense??? They have a perforated pipe which does a slight S as it passes through a glass-fibre packed muffler.

Not sure what I will fit when I get a new muffler soon, but going 3" if it can possibly squeeze in.

[rick130]

These mufflers https://www.aulro.com/afvb/ are popular in roundy roundy race circles in the US, (the bloke that designed them supplies the majority of Nascar teams with exhaust systems) and they are relatively cheap, (not including freight) and a massive array of configurations in, out, offsets and sizes, as well as very compact in size and as there is no absorbent packing, cant 'wear' out.

From here Spin Tech Mufflers (http://www.spintechmufflers.com/spintech/spintechindex.asp)

Otherwise, just a good old fashioned glasspack straight through muffler with a resonator near the end of the tailpipe.

[1103.9TDI]

rovercare Quote:



Mine's 3"



Mines a lot more than 3 inches!:p:D, but my exhaust is a 3 inch, straight through, mandrel bent system, that runs along the left side and exits the rear. It is clean and efficient, ie: nothing to snag on and nothing like letting an Isuzu turbo engine breeeeth. Noise!.....who cares, it's behind me....Legallities!, it's less extreme than a souped up ricey, or a throaty V8, so they really have no reason to pester me.......

[Dougal]

These mufflers http://www.spintechmufflers.com/spintech/productimages/2.jpg are popular in roundy roundy race circles in the US, (the bloke that designed them supplies the majority of Nascar teams with exhaust systems) and they are relatively cheap, (not including freight) and a massive array of configurations in, out, offsets and sizes, as well as very compact in size and as there is no absorbent packing, cant 'wear' out.

From here Spin Tech Mufflers (http://www.spintechmufflers.com/spintech/spintechindex.asp)

Otherwise, just a good old fashioned glasspack straight through muffler with a resonator near the end of the tailpipe.

Interesting those ones, but freight would kill the attraction pretty quickly. What does the resonator acheive and what's the effect of not having one (it currently has just the one).

As for legalities, we have 6 monthly vehicle inspections.

[rick130]

freight from the US mightn't be so bad, particularly as some of those SpinTech mufflers are pretty compact.

Generally a 'resonator' is used in the tail end of the system to restrict
the harmonics or resonances that often occur with a lot of engines and exhaust at critical periods, usually around the 2000RPM mark in my experience. When this happens your cabin becomes the new, secondary muffler and it isn't pleasant at all.

When I built the 3" system for the Tdi, apart from it being objectionably loud, right at 100km/h the whole cabin 'boomed' and really hurt the ears. I jammed a short resonator in the tail pipe and it's mostly tamed the booming, at least 95% of it any way. Interestingly it had hardly any perforations in it, and they were tiny, but geez it worked well.
When I eventually install a main muffler, it'll hopefully be nice on a trip again.
Anyone that says a four cylinder turbo diesel system doesn't need a muffler is either deaf or seventeen years old. :rolleyes:
It's a crap sound anyway. :D

[Bush65]

I have 3" mandrel bends etc. ready to make the exhaust for my rangie. The 3" muffler pictured was locally made copy of a well renowned USA muffler- the guy makes them for race cars.

Should have little resistance IMHO.

[rick130]

I have 3" mandrel bends etc. ready to make the exhaust for my rangie. The 3" muffler pictured was locally made copy of a well renowned USA muffler- the guy makes them for race cars.

Should have little resistance IMHO.

Would that be like one of these John ? https://www.aulro.com/afvb/images/imported/2008/06/202.jpg It's a Cherry Bomb Vortex.

[Bush65]

Would that be like one of these John ? It's a Cherry Bomb Vortex.
No. If you look at the 1st pic you can make out where the baffles are welded inside.

[Dauntless]

Have you decided on a muffler yet? I'd go with a simple but effective hotdog type muffler if I were you. Definitely get something straight through with a perforated core. I use 2.5" straight through Berklee BS0806 and BS0428 on my Volvo, and I love them.

[justinc]

I have a 2.5" system, from turbo outlet to tailpipe. It has a centre muffler, which is relatively high flow, and no resonator. Shortly i'll be removing the centre muffler and fitting a straight through glass packed resonator at the rear to speed up exhaust gasses while eliminating the booming at certain revs.

We don't have vehicle inspections here Dougal, must be a pain over there!:mad:

JC

[Dauntless]

We have yearly inspections here in NSW.

A resonator will cut down on booming and raspyness, but they usually aren't necessary on turbo engines, especially relatively low revving ones.

I'd use something like these below:

http://www.bestmufflers.com/bshop/index.php?cPath=343_344&osCsid=7b1e3ab858cfad52594ed8d52068f9ca

https://www.aulro.com/afvb/images/imported/2008/07/197.jpg
https://www.aulro.com/afvb/images/imported/2008/07/198.jpg
https://www.aulro.com/afvb/images/imported/2008/07/199.jpg
https://www.aulro.com/afvb/images/imported/2008/07/200.jpg

[Dougal]

Still have done nothing about it, it's been an excellent snow year so far and skiing is cutting into my spare time.:)
Recovering from skiing means I don't get much done in the rest of my spare time.:D

That last muffler picture is the same package as my current one. I really should go visit the local muffler shop and see what they can get.:angel:

[Dauntless]

No worries. Would you mind posting a video of the exhaust with good quality sound on Youtube, both before and after? :)

[Dougal]

I finally paid a visit to the local muffler shop today.
A 2.5" straight through muffler is pretty cheap ($150), cheap enough to try it and see how it goes.

Don't hold your breath, I've got plenty of other things on "the list" before this crops up.