TheSamba.com :: View topic - Thunderbird exhaust quality vs. current EMPI, etc...

Sat Jul 17, 2010 5:03 pm

WOW...it has been a long time since I've posted in the Samba...mainly, because I forgot my login but all the sudden here tonight I've remembered everything it seems!

Doing some "overhaul" items on the bus and really want to finally dig in deep and get a new exhaust. Motor in question is a 2.0 Typ IV in my 72 Westy w/ dual 36mm DRLA's...

Currently, have kind of a custom setup using an old empi header and a flowmaster muffler...while the purr on accel is cool...it has grown to be too loud for me and has always caused a backfire (mis matched flanges /pipe diameters I think to blame...) and I'd really just like to get something new...but something good.

My past experience with a single EMPI (chinese i believe) single quiet back with the header was that it was a piece of junk that rotted out in a matter of 6 months! Sad.

I was looking at the Type IV Store and have kept my eye on the Thunderbird system for some time. It looks the same as the empi system. I'm hoping someone can tell me that there is definetely a difference in quality.

Anyone? Otherwise...a suggestion for a good exhaust for on the bus? I have the trapazoid flanges...so I can easily run the Thunderbird...but hate to spend the 200.00 if its the same quality as the EMPI unit for about 100.00 less!

Joe

Sat Jul 17, 2010 5:07 pm

Never use EMPI and Quality in the same topic.

Sat Jul 17, 2010 5:16 pm

lol...this I have learned/know. Just want a good quality system for the TYPIV motor...

So many options for the standard upright 1600cc based units...not much for the TYPIV...hoping someone has experience with the Thunderbird unit.

Sat Jul 17, 2010 5:16 pm

Glenn wrote: Never use EMPI and Quality in the same topic.

not even when the word "awful" is used too?

Sat Jul 17, 2010 6:00 pm

I have the Thunderbird in the NLA '75-'78 style. The quality is disappointing although it does the job. It's thin, light, and rusting fast. It should be a crime to sell exhaust systems made out of plain thin mild steel w/no plating or anything. Even the paint they use is just for the shelf, it peels right off the first time you run it.

Sat Jul 17, 2010 6:07 pm

WhirledTraveller wrote: I have the Thunderbird in the NLA '75-'78 style. The quality is disappointing although it does the job. It's thin, light, and rusting fast. It should be a crime to sell exhaust systems made out of plain thin mild steel w/no plating or anything. Even the paint they use is just for the shelf, it peels right off the first time you run it.

so true. the T'birds on my beetle fell apart shortly after I bought it. My replacement set looked awful after a few months. Such soft, thin steel.
I still had the old tailpipe lying around. Just for fun recently I tried using my MIG on it. even at the lowest setting all I could do was blow more holes in it.
It's not one of those crap eBay MIGs either. It's a good commercial one which I bought specifically for how low it can go.

The exhaust situation for type4 motors is pretty sorry at the moment too.
I'm just going to lop off the exhaust past the collector and make a muffler / tailpipe out of bits of the exhaust from our dead ex DD.

Sat Jul 17, 2010 7:21 pm

man...that really stinks. I was hoping that it was of better quality, etc. Maybe I'll just get the other than and pay alot less and worry about it again in 1 year! Oye.

Sat Jul 17, 2010 11:48 pm

This? At least for the muffler?

http://iconicautomotive.com/VintageSpeedGermanLook...ngine.aspx

Sun Jul 18, 2010 4:56 am

The single quiet mufflers that the Type 4 Store sells are not Empi, they are Bugpak. I have had one on my '72 Westy for about 4 years and it has just started showing signs of needing replacement. My bus is driven daily and is not garaged. I have had a Cherry Bomb muffler on my other '72 for about 3 years and it is in worse shape then the Bugpak.

Sun Jul 18, 2010 6:09 am

BUGSTUFF wrote: This? At least for the muffler?

http://iconicautomotive.com/VintageSpeedGermanLook...ngine.aspx

now that is sweet...and eleminates the header/extractor style setup as well. Looks more "OEM". Anyone ever run one?

Sun Jul 18, 2010 7:55 am

It is beautiful....but unless its less restrictive than stock....its an expensive liability. I would love to know what the flow path is.

The stock muffler actually does decent for such a compact unit....but it is very circuitous and radiates an ass-load of heat. Its is actually a resonator with at least two direction changes inside.
The stock muffler is not a bad design...just generally poor execution as a trade-off for quietness.
A good for instance is that the Ernst version of the 411/412/1.7/1.8 muffler has a bout 15 % larger internal volumes and 25% larger perforations in the center tube. It runs worlds away better and cooler than an OEM, Wagner...or those prroly welded Dansk units.

Just guessing.....but it looks like the iconic unit simply has a twin center tube. If the inlets simply dump into the main body to feed the center two outlet pipes (which are generally perforated)....it should do much better than stock...because thats a single direction change.
the stock units have 1 and 2 going all the way to the left end and dumping and 3 and 4 going all the way to the right and dumping....and then having to find their way to the center tube and change directions again.
Ray

Sun Jul 18, 2010 2:18 pm

There is the Tangerine Racing one but I have heard not experienced that they are expensive and possibly a long wait to get one. Also heard that Jake may be working on a system himself but nothing on the market yet.

I will be doing the 72-74 heater box conversion eventually and I hope before I have to do it when my current set up wears out that there will be more choices by then.

Sun Jul 18, 2010 2:50 pm

We have been running the thunderbird for 4 years now, I got it with the ceramic coating, which held up for about 4 weeks. Now it looks like a total rust bucket exhaust with the silincer already welded up twice. The header is quite ok though, although the coating was crap. Maybe you could get the Thunderbird header and get some other muffler on there. Make sure to get a decent ceramic coating on the whole system too if you want it to have any chance to last.

Sun Jul 18, 2010 4:12 pm

raygreenwood wrote: It is beautiful....but unless its less restrictive than stock....its an expensive liability. I would love to know what the flow path is.

The stock muffler actually does decent for such a compact unit....but it is very circuitous and radiates an ass-load of heat. Its is actually a resonator with at least two direction changes inside.
The stock muffler is not a bad design...just generally poor execution as a trade-off for quietness.
A good for instance is that the Ernst version of the 411/412/1.7/1.8 muffler has a bout 15 % larger internal volumes and 25% larger perforations in the center tube. It runs worlds away better and cooler than an OEM, Wagner...or those prroly welded Dansk units.

Just guessing.....but it looks like the iconic unit simply has a twin center tube. If the inlets simply dump into the main body to feed the center two outlet pipes (which are generally perforated)....it should do much better than stock...because thats a single direction change.
the stock units have 1 and 2 going all the way to the left end and dumping and 3 and 4 going all the way to the right and dumping....and then having to find their way to the center tube and change directions again.
Ray

Ray the iconic unit is from "Vintage Speed Shop" in Taiwan and I'm also curious about the internal construction. However they seem to know what they are doing, they have dyno numbers posted and youtube videos up with the sound etc. I'm really liking the looks and may buy one. I seem to remember seeing some sort of internal diagram somewhere but now I can't find it. There is this from their website, a different exhaust but seems similar construction:

http://store.vintagespeed.com.tw/images/stories/pdf/P01.pdf

Somebody posted a good video of the exhaust running on VintageSpeed's feedback thread, page 2. Seems a little loud but throaty in a good way, unlike my Thunderbird which sounds a little like a honda civic with a hole in the muffler.

http://www.thesamba.com/vw/forum/viewtopic.php?t=347416

Sun Jul 18, 2010 4:41 pm

If you look at their type 1 exhaust pictures....they have ghost cutaways on them. If the type 2/4 exhaust is anything like those....they do know what they are doing. I;m thinking along the same lines. That may be just the ticket for my 412. Ray

Sun Jul 18, 2010 4:48 pm

I was thinking the same thing after looking through that information, etc. Though, something that I think is a bit ridiculous is the shipping price. CA to NY they quote $95 to ship...thats their "international flat shipping rate". Thats through the Iconic site...

almost went for this... but 95.00 shipping within the USA? Eh... must be pulling it from Taiwan!

Joe

Sun Jul 18, 2010 5:06 pm

Ray, I found the diagram I was looking for on this thread here:

http://www.thesamba.com/vw/forum/viewtopic.php?t=397928

In it "VWTaiwan" says that the bay window muffler is similar to this muffler:

The location of the outlets on the bottom right of the bay window muffler implies that they connect through the passenger side internal baffle into the center chamber, the basic configuration is the same as shown except the location of the outlets.

Sun Jul 18, 2010 5:40 pm

Keep a sharp eye on the collector on the Thunderbirds. this was one of the main failure points on both sets I had. Probably from the leverage of the vibrating load of the muffler. i don't know. I just know the first one broke and fell off and the second one was perforated.

Wed Jul 21, 2010 7:27 am

well...was going to get a dual muffler empi unit from Larrys Off Road...ordered Sunday...but finally got a call yesterday and they are sayings its "out of stock" and probably will be two weeks before it'd be in. Thinking alternatives now.

Talked to the local VW guru the other day...he thinks he may have a few good bus mufflers (OEM) at home...one which I could get.

My question...would the OE exhaust be too restrictive on a 2.0 GE code TYPIV w/ Dual 36mm Dells....or the best bet for now?

Joe

Wed Jul 21, 2010 11:35 am

checked back with the guru today...

He has NEW Lestristz mufflers...a few of them. Problem is, they are for the 411 from what he is saying.

Does anyone know if the muffler would work on the bus? I know the tailipipe direction would be off...but that could be fixed. OEM/German , NEW for $100.00 is what he said I could have one for...not a bad deal...if it'll work.

Anyone with info out there?

Joe