Hi All,
There is a truck up my way that sounds really throaty. I bumped into him today and asked him what exhaust system he was running, he said he's not, he has just removed the muffler
Is this good or bad for the motor, I'm not technically minded so I'll just put the question out there

Cheers,
Patchy

 

I tried it but it did my head in - too loud! I'm running a 4" turbo back system with 2 'Hurricane' mufflers now.

If you have the Ford Australia turbo downpipe fitted you could delete the muffler. Any good exhaust shop could do it - they just make up a 3.5 inch diameter 'muffler delete' pipe.

No adverse knock-on affects on the engine/turbo from this that I'm aware of - in fact it would be an improvement as your EGT should drop with the removal a slight restriction. The problem is that the main restriction is the FA 2.5 inch downpipe which sits between the 3.5in turbo outlet and the stock 3.5in exhaust!

 

Diesels don't run "closed loop" like petrol engines, so you can do whatever you like to the exhaust as soon as it leaves the engine and it won't know any difference (unless its a new diesel with DPF). As Simon mentioned, the more flow/larger the exhaust after the turbo the better.

On my 7.3, I had a 4" dump/straight pipe from the turbine housing that exited just behind the cab (before the rear wheels). It sounded mean, and I am pretty sure there was permanent hearing damage caused to anyone following me in a tunnel when I downshifted. I didn't find the noise annoying at normal cruise, but as soon as it got under load it was too loud for continuous use - I didn't do any towing, but long uphill stretches were a bit of a pain.

If you do any towing, I would definitely suggest a muffler - but even running it behind the rear wheels would help a lot.

 

So Ford Aust put a step down restrictor pipe straight off the back of the exhaust housing?

Wow - let me guess, these utes are slow to spool up and they suffer high EGT's, possibly even cracked exhaust housings or tip rubbed, over temped exhaust wheels?

The goal is to have a step up diameter pipe straight off the housing, this stops the exhaust gasses spinning and gets them flowing properly. So that 4 inch dump sounds good

 

Might have a play with this I got twins out the back of mine so it should not be to noisy from the cab

Cheers,
Patchy

 

Patchy, check your turbo down pipe. If it is the crap FA 2.5" one the best $wise way to get an improvement in all aspects would be to swap the FA pipe out - which is easy if you cut it out, and replace that section with a 3.5" DP to hook-up to your existing system.

 

I got a 3"DP with this tag



Now you got me a little confused, Lot of mention of the FA DP,
so where does the Brazil one fit in the grand scheme of things
Still learning things about my truck

Cheers,
Patchy

 

Looks like a picture of a tail pipe there, looking up from the ground, yep 100% pure Brazilian no doubt about it - you can tell cause there's no hair !

You have to work your way forward and check where the exhaust goes up past the footwell on the way to the turbo, that's where the Down Pipe lives. That is where you'll find the FA DP - a lot of welded pieces choking it down to 2.5"

So you have a twin system hanging off the back of your stock Brazilian tailpipe?

This picture shows the FA DP above the stock Brazilian tailpipe - the little strangle box is clearly visible.

 

Here is a picture of the MBRP 4" turbo back exhaust I bought of Clay and shipped over USAtoAUS. The pipe on the lower left is the muffler delete pipe (I wish I bought the muffler now).

The 4" DP ended up being very hard to fit and had to be dented into submission - so much so that I think I may have had a better result getting a 3.5" DP into a 4" exhaust.

 

The shot was taken just before it up sweeps
to the turbo ,directly under the fire wall
DP 3.5 will be the way I go, thanks for the info

Cheers,
Patchy

 

A 3.5" DP will be the way to go. My firewall was "massaged" to fit the 4" DP on my 7.3

My current 6.7 (which is a quieter engine than the 7.3 anyway) has a 4" straight pipe, and sounds good (not too loud). It exits after the rear wheel.

 

a bit OT but how the 6.7L Adrian ??? very interested from someone who has Aussie experience. Maybe a fresh thread. Oh and we like pics

 

G'day Patchy,

There's a good discussion on this subject on the tread "MODED EXHAUST" on page 5 of this Aussie Chapter forum.

Worth a read through as most of us have been through this saga.

Cheers,
Reg

 

I think I can oblige

 

Thanks for that Reg, Whish I found it earlier a good read
The only hassel I seem to going to have is finding someone in Cairns willing to do the fit

Cheers,
Patchy