Thread: Fitting the thru pipe to replace the muffler, worth doing?

Cherry bomb, hot dog, it's essentially a high flow muffler. If you go to an exhaust shop and show them what you have, and say you want something with more flow and minimal noise increase I'm sure they'd be able to sort you out fairly cheaply

Originally Posted by vnx205

I am prepared to believe that a straight through pipe might make the turbo behave differently, however, I would be very suspicious of anecdotal claims about how much better the vehicle performs.

I am convinced that it is natural for people to believe that if they are making more noise, they must be going faster or accelerating harder.

I have seen this phenomenon with motorcycles and with kayaks. Back in the 70's I was assured by a Honda SL125 rider that his bike went a lot better since he fitted his (louder) Pascoe aftermarket exhaust to his otherwise standard bike.. He was the same weight as me, so I line up my completely standard SL 125 beside him and we did several drag races.

There was absolutely no difference between the bikes on any of the runs. All he could say after that was, "Well it sounds better than it used to."

I have heard claims from a number of people about how fast those Hobie kayaks are with the Mirage pedal drive. None of them have been able to even get close to keeping up with me in my sea kayak. Even a couple in a double using both the pedals and their paddles couldn't keep up.

Their hull shape is so inefficient that as soon as you try to go fast they create a lot of gurgling noise and the loudness of that noise fools people into thinking they are going fast. They aren't. They are just stirring up the water a lot and making a lot of noise.

I'm sure the same effect can be seen with vehicles. The one making more noise just naturally seems faster.

That doesn't mean that there can't be an improvement with a louder exhaust, but it does mean that it is possible to be absolutely convinced of an improvement when there isn't one or to be fooled about just how great the improvement is.

(Maybe that explains the popularity of Harley Davidsons.)

Yep.

Does anyone have a pic of the guts of the stock D2 muffler ? (the inlet/outlet are offset)

The 300Tdi Defender main muffler was a straight through 2.5" bore with a perforated tube. (the stock system was 2, 3/8"/60mm)

It really was a placebo effect if you cut it out and claimed it went better/spooled faster sans muffler.

I actually have a brand new offset Hooker Aerochamber muffler (3" in/out) in storage here.
Hmmm.

Originally Posted by vnx205

I am prepared to believe that a straight through pipe might make the turbo behave differently, however, I would be very suspicious of anecdotal claims about how much better the vehicle performs.

I am convinced that it is natural for people to believe that if they are making more noise, they must be going faster or accelerating harder.

I have seen this phenomenon with motorcycles and with kayaks. Back in the 70's I was assured by a Honda SL125 rider that his bike went a lot better since he fitted his (louder) Pascoe aftermarket exhaust to his otherwise standard bike.. He was the same weight as me, so I line up my completely standard SL 125 beside him and we did several drag races.

There was absolutely no difference between the bikes on any of the runs. All he could say after that was, "Well it sounds better than it used to."

I have heard claims from a number of people about how fast those Hobie kayaks are with the Mirage pedal drive. None of them have been able to even get close to keeping up with me in my sea kayak. Even a couple in a double using both the pedals and their paddles couldn't keep up.

Their hull shape is so inefficient that as soon as you try to go fast they create a lot of gurgling noise and the loudness of that noise fools people into thinking they are going fast. They aren't. They are just stirring up the water a lot and making a lot of noise.

I'm sure the same effect can be seen with vehicles. The one making more noise just naturally seems faster.

That doesn't mean that there can't be an improvement with a louder exhaust, but it does mean that it is possible to be absolutely convinced of an improvement when there isn't one or to be fooled about just how great the improvement is.

(Maybe that explains the popularity of Harley Davidsons.)

After 12 years of D2 driving I'm surprised that the comparison with my original one is quite great and it is not noise induced and there appears to be good low down torque with lock up in fourth holding down to 1600 rpm. However in fairness I do not know whether the ECU has been chipped or not, but I do not have to plan my overtaking the day before in this one. However I am planning to fit a silencer in place of the straight through pipe at some time.

Nick

Totally agree with Disco Muppet, originally removed mid-muffler 18 months back which made a difference throughout the rev range, and then a couple of months back removed the cat, and definitely spools quicker at lower revs and the turbo noise sounds good. Car is noticeably more eager to rev now.

Also have to say the drone can be bad at times, going up hills when loaded, too loud, and am about to get a hot dog put in which should help. This is the first time I have ever done a mod that might effect performance in a negative way, but it can be too harsh at times, especially when the wife is on board and hence stereo turned down lower than usual.

But overall, definitely worth removing the muffler and cat as a cheap way of getting additional performance.

I really cant believe there is a group of people that think a TD5, {with the absolute BEST [exhaust] intentions}, thinks a COMPRESSED AIR exhaust leak sound is any good----
seriously?
I hear LOTS of 3" rattlers around the Coast,, and they ALL sound like modern farts,,

A well tuned td5 with decent exhaust sounds great at higher revs , unlike the toyonissa****i 4cyl oilers with straight throughs, and the compressed air is used on the induction side Pedro

Originally Posted by Pedro_The_Swift

I really cant believe there is a group of people that think a TD5, {with the absolute BEST [exhaust] intentions}, thinks a COMPRESSED AIR exhaust leak sound is any good----
seriously?
I hear LOTS of 3" rattlers around the Coast,, and they ALL sound like modern farts,,

Is that whilst you are standing at the pump refuelling pedro
I have decatted mine and removed the rear muffler it spools up quickly with no noticeable increase in the cabin noise its also de egr'd and turbo wound up

Originally Posted by ramblingboy42

I drove my td5 for seven years with a straight through pipe.

It immediately improved everything but after a while you just get used to it. I removed my egr at the same time, turned the wick up on the turbocharger as well.

did about 200,000km in that mode.

my fuel usage was more like 9-9.5 litres/100

with the taller tyres, rpm at 2000 I could get down to 8's down the newell and across NSW.

Sound OK to me...