Outer Limits 4x4 Board

Hi everyone,
I was wondering if my 300 tdi would benefit much from a larger exhaust. I was thinking 3". Any comment suggestions would be appriciated.
Thanks

You'd be better to spend your money on a bigger intercooler and adusting your injector pump

EXHAUST

3" might be abit big thou ? ? ?

I'm doing the pump, lifters and boost as well, but just wondered if anybody had tried it. It looks like a 2 1/2" already so I think under 3" would be a waste. It would be cool if it sounded tough as well so maybe just cut the cans out.

3" is a waste of time!
the turbo stops any real noise, the standard exhaust is 65mm.
I have removed:
the catalyst front section
rear box
and left the middle box in situ.
Be carefull taking the Boost much over 1bar as the headgaskets aren't up to much more.
adjusting the pump etc can be worthwhile tho!
see here for detail:
HERE

Thanks, thats a great link too.

TC, Aussie Tdi's don't use a catalytic converter, so at least we don't have to remove it

With the standard Garret T250, I feel the intercooler isn't up to the job. I've recorded turbo outlet temps of 104 degrees celsius, with the intercooler outlet temp of 64 degrees @ 13 degrees ambient !
Next step is to fit an exhaust gas pyro and see what is going on.

Another option is to instal DTS's (now MTQ Engine Services) Mitsubishi TDO4 turbo and new exhaust manifold. http://www.dynamicturbo.com.au/default.asp?p=105
all at a claimed 12lb boost, compared to 15.5 psi of the Garrett.

muzz, i have seen the performance increase going to 3" ex. there is an acceleration improvement and noticable too
my 200 tdi used to keep up wiyh a mates 300 tdi (ute vs. stnwgn.)
he could pull away in 4th.
with then 3" from turbo ex. housing he could pull away in all gears.
when he towed a motorbike trailer with 3 bikes our performance was even again.
BUT, i would suggest checking exhaust temps before and after to prevent damage. the performance increase could be from more boost b/c of less back pressure.
if you don't have air-con put the biggest most efficient intercooler you can. this is the easiest torque improver you can get.
from people i have spoken too i think the ultimate would be bigger intercooler, bigger exhaust, adjusted injector pump, then if you could afford it change the turbo.
if your interested, search for lpg assisted diesel engines here.

Rick
The catalyst is a saving then!
The real gains I've seen are from larger intercoolers
Although I have no room for one as I have recessed the winch into the space.
My 300tdi accelerates quicker and builds boost faster since the cat and rear box was removed,
The rear was removed to free up space for the rear winch.

But the weak link on these engines is the Head gasket!
Mines running 1bar 15psi measured at the inlet plenumb chamber rather than the intake side of the Turbo.