What exhaust you all recommend for my tdi300 with upped boost and a refreshed head, im thinking 2.5inch straight through system (noise not an issue) tell me what you all think...

Fusion has a straight through on his Tdi. I followed him around on the Blackwood day and sounds Ok for a diesel I guess and not to loud (It's No V8). I don't know what it's like inside but I think he said it drones on the hwy. I thinks you can hear it in the Otways Report.

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Cheers, David.
My Land Rover has made me a better Mechanic
96 Disco 1 V8 Auto, Vroom Vroom!!!

All I did was remove the main (middle) muffler and replaced it with a 2 and a half inch straight through muffler. Nice little hum and let's the gases out quicker.

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95 Disco 300tdi - Now with MORE BOOST
Cheers Simo

i diched the main muffler in mine it aint that loud made a huge difference tho

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thanks Jono
Skip 1995 D1 disco tdi auto
Tin Worm the lickerish al-sort scat tojo diffs 42" iroks
Modern Times 87 falcon van soon to have au xr6 motor and boost

I replaced my centre muffler with a straight through sports one also.
May have made a difference on slightly earlier spool up but that may be wishful thinking, no facts invloved here and the extra noise can give one the thought of a performance increase. But in reality, how could it possibly?

There is no science to back that up anywhere and it has been proven via dyno tuning that size does matter and too big and too little back pressure does drop performance.

So, I tweaked the pump, better intercooler and gas and now she goes well for a Tdi. Still no dyno figures but I do have the on/off switch for the gas and its definately noticeable.

The drone from my old V8 RRC was at times very annoying, it was fine the first 15-30 minutes of a trip and after that not even the tyre noise blocked that out.

I would recommend do very little, I have personally not seen any factual evidence to make a noisy exhaust worth your while.

Just my thoughts, I did hear HBWC's exhaust the other day in Adelaide and that was not too noisy but I also do not sit in it for hours.

I think you will find that is not the case with turbocharged engines. The turbo spins up faster with less back pressure from the exhaust. The engine probably does not get to see much of the effects of the exhaust system as the turbo provides the back pressure towards the exhaust ports.

thanks it dont drone in the cab if i dont have the window down i carnt even hear it in the cab

also to little back pressure is really only in the petrol world the turbo will supply more that anoth pressure in a diesel application

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thanks Jono
Skip 1995 D1 disco tdi auto
Tin Worm the lickerish al-sort scat tojo diffs 42" iroks
Modern Times 87 falcon van soon to have au xr6 motor and boost

Quote:"There is no science to back that up anywhere and it has been proven via dyno tuning that size does matter and too big and too little back pressure does drop performance."
Where do you get this crap from, greatest load of horse **** I ever heard.
How many F1 and Drag Cars (to name but a few) do you see running around with mufflers and restrictive exhausts, how many high performance racing cars have mufflers, why do Ferrari and others spend millions building free flowing exhausts that will be accepted by rego authorities, use a bit of commonsense, if you restrict the flow of exhaust you will lose power, same as if you restricted the inlet side of an engine, after all it is only a pump, Regards Frank.

spot on. between engine and turbo is a different story, but post turbo you just want to the get gasses out ASAP.

i replaced the centre muffler with a straight through bit of pipe. made no difference to performance and barely any sound difference. slighty deeper at idle, but anything above idle the engine just drowns it out anyway.

I'll be making a full 2.5" system when i get around to it, with single straight through muffler in the rear.

Thank you for your words of rudeness.
Do I blush now?

Are we talking road or F1 cars?
We are talking about a ancient diesel design that is designed to last not just good for one race or a quick drag.

A tuned pipe mandrel or other, 2,3 or anything can make a difference sure.
Taking out a muffler or putting a straight through exhaust in willy nilly will not.

I spend many hours in my mates exhaust technique shop selling and installing all sorts of stuff mainly that looks good and in general just makes more noise.
Just paint cans really but thats what people like.

We sold the odd Remus system too, they are not loud but tuned to the exact specification of each car. They cost a bundle and all in all, even their german sales rep tells us that its tiny, its a feel good thing.

Do exhaust, injection, cams clutch and driveline mods and now you are talking.

Now please Frank if you want to insult me do it via PM or better still, refrain from doing so in general. If I contribute to a post its from real life experience, if you feel I am wrong thats fine but let that be the end of it.

Big loud exhausts in general do not help, properly tuned for a specific engine will but still only marginal.