Bung Removal From The Zorst

[God666]

A topic that cropped up in jmi8's thread on "Territory Turbo Edit by Tunehouse" was the issue of the bung removal in the front of the centre muffler in the inboard pipe (see original thread Click here! I thought I would start a new topic as the original was getting a bit messy and hijacked.

See pics

A few guys have cut off the front pipes and had the bung punched out or ground out however, I was not keen to do this and questioned whether you could remove the bung by going in from the single pipe at the rear. Well, the answer is yes, all it takes is about 10 mins to remove the muffler and a further 45 mins, armed with a piece of 25mm rebar about a metre long and about a dozen round blocks of wood about 40mm dia and 50mm long and one 40mm dia piece about 200 mm long. Sound a bit bizarre but it works.

Once you have the muffler off, slide your piece of rebar in through the single 3in rear pipe and aim for one side of the bung. A few quick firm taps and the bung pivots and breaks the spot welds. Now the the bung is at 90 degrees to the way it normally sits, drop the blocks of wood, one at a time, down from the front of the pipe (the single 2.25inch blocked pipe). Once the tube if filled with the blocks of wood, just progressively hammer the blocks further in (adding more blocks as necessary) ensuring that the bung remains at 90 degrees to the pipe. As the muffler internal pipes are slightly larger than where the bung was fitted, it quite easily slides through and out the back hole. Then simply make sure you have removed all the block of wood and refit the muffler.

Is the car louder without the bung..... maybe ever so slightly louder but if you didn't tell anyone, they would be none the wiser. The TT zorst is quite loud anyway in stock form.

Is there more power..... um, not sure, it just seems to breathe and rev easier.

And why is the bung there? .... I suspect that the car was right on the limit for noise emissions so that was an easy fix. I cannot think of any other sane reason, it just seems to defy belief.

Oh... and the blocks of wood, they came from a small tree branch lying in the back yard. The reason they are cut into short pieces is that the front pipe has two curves in it and the short pieces slide around the corners and still work fine as a punch.

Oh, and I forgot to add, in the other topic, I questioned as to whether you could drop a long holesaw in from the rear. Answer is no as the rear 3 inch pipe is right in the middle of the two internal 2.25inch pipes.

Edited 23/06/07 08:01 AM by God666

[ZAP]

Well done, I still do not understand how you got the bung out, but you proved it could be done.

As for the theory about why, I am sure it is both power and noise.

It is noticable louder, but not over any limits. I would think it is no louder than my F6, but it does rev and pull much harder.

[Twinpiston]

Mine was really well welded in so don't think their was anyother way of getting the bung out with out buggering it, but well done and I guess if I had the time and a hoist I would have probably tried the same.

P.S Just came back from a weekend jaunt, fuel consumption for the trip went from about 11.7-.8 down to 11.1 so about .6 to .7 ltrs/100k's better off!!!!

[paulie0735]

Well done. Based on the difficulty we had getting mine to break off at the welds I doubt it would have worked on mine. Also had somebody tell me theirs was just pressed in, no welds at all.

[God666]

Yeah, it took a bit of a bash to get the bung to break out however, that piece of rebar weighs about 3.5kgs so you can get a good bit of kinetic energy with that sort of weight.

Besides, I love a good challenge, particularly when someone says it can't be done :spoton:

Edited 24/06/07 10:59 AM by God666

[TTonka]

:

Yeah, it took a bit of a bash to get the bung to break out however, that piece of rebar weighs about 3.5kgs so you can get a good bit of kinetic energy with that sort of weight.

Besides, I love a good challenge, particularly when someone says it can't be done

bowdown: Top work, Always been a big fan of the brute force and ignorance solution. Seriously though, Good practical common sense technique.

I got mine taken out last week or would've tried the same. Economy seems better around town, noise Ok especially under a bridge or tunnel, shifts freer.

Only concern is that it seems to be harder to hold at 60km/h

[God666]

I have to correct my earlier observation about the noise level with the bung removed. I did note that it was "ever so slightly louder" however, now having driven it around for a week, it is definitely louder but not harsh at all and definitely not in the range to get you in trouble with the Plod. Starting the thing in the garage now makes the house rumble, never did that before. And yes, it now has a spirited sound to it. Way louder than my XR6T ever was (it had a standard zorst).

The most important thing from my perspective is that at highway speed, it is still nice and quiet as I spend a lot of the time on long distance trips.

[cobramad]

I have to correct my earlier observation about the noise level with the bung removed. I did note that it was "ever so slightly louder" however, now having driven it around for a week, it is definitely louder but not harsh at all and definitely not in the range to get you in trouble with the Plod. Starting the thing in the garage now makes the house rumble, never did that before. And yes, it now has a spirited sound to it. Way louder than my XR6T ever was (it had a standard zorst).

The most important thing from my perspective is that at highway speed, it is still nice and quiet as I spend a lot of the time on long distance trips.

Glad to see someone getting the damn thing out without cutting and shutting!! We managed to remove a customers by cutting the pipe right next to the weld at the muffler, on the pipe side and lo and behold the core plug just twisted and was coaxed thru the main muffler. Simple matter to then reweld the pipe without having to realign the flange and muffler. Food for thought.... and it made the TT sound better but not too much louder.

Mal.

[Red Territory]

Hi guys

I'm about 3 weeks away (so the dealer tells me) from picking up my New Seduce Turbo Ghia. I have been reading about these bungs.....reckon mine will have to go very quickly.

My question is....has anyone measured the power gains, if any, of the bung removal.

thanks in advance

[ZAP]

My Bum-o-Meter says it is noticable and worthwhile, even if it is just for the noise