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Freeflow exhaust

Posted: 07 Aug 2012 12:51
by erasmusdries
Hi everyone

I need some advise.I need to replace/fix my exhaust.Is it worthwhile to put a freeflow exhaust on a naturally aspirated diesel engine.I use the exhaust gasses at times to inflate an airjack. Got a quote from SAC=R2800. :think: :helpsign:

Re: Freeflow exhaust

Posted: 07 Aug 2012 14:34
by Kagiso II
Waht does u means wif freeflow exhozt? just the exhozt starting at the flanges OR the branches too??

Boezman has a 63 mm straight pipe [NO exhozt boxes] .. he whstles slightly -- but thats it

[also - oompi asking: is that evil piece of CAT still on yer veehaicul? :oldtimer:

Re: Freeflow exhaust

Posted: 07 Aug 2012 15:02
by erasmusdries
Only the exhaust,not the branches.

Re: Freeflow exhaust

Posted: 07 Aug 2012 17:02
by Herrie
'n hele paar diesel Patrols het net uitlaar pype sonder uitlaat bokse!

Re: Freeflow exhaust

Posted: 08 Aug 2012 07:50
by Peter Connan
Al the diesel guys I know who have removed all their silencers have turbos. As far as I know, the turbo acts as a muffler itself, smoothing out the pulses from the cylinders for a very similar effect to a silencer.

I do not think this approach would work with a non-turbo engine?

I do not know how much effect a free-flow system would have on a non-turbo diesel engine, but I guess it depends on the current size and restrictions, relative to the volume of gas generated?

Re: Freeflow exhaust

Posted: 08 Aug 2012 09:45
by ricster
Yeah, the turbo is in itself the only muffler a turbo-ed diesel needs. Non turbo, would need a small muffler just to take the big bang away, but is it necessary ..... I don't think so. At the moment I only have the small rear box on mine and will be removing it soon. Try it without and if need be add a box in afterwards.

Re: Freeflow exhaust

Posted: 03 Jun 2015 11:41
by SJC
So what would be the recommended mod for a td42ti: freeflow or straight pipe?
Can anyone explain the pro's and cons of these two to me?
It would cost a lot less to install a straight pipe oppose to a freeflow system...right?

Re: Freeflow exhaust

Posted: 03 Jun 2015 13:26
by ricster
Don't even waste time getting a quote for a freeflow.... just go 3" pipe from the turbo exit to the end. The turbo chops the frequencies so much that it is a muffler in itself. Your motor will breathe better and your turbo will be able to spool up faster.
There are a LOT of 4.2 Patrol turbo motors running around like that and it gives the motor a nice grunt sound and you will hear the turbo whistle slightly..... sounds so good !!

The freeflow will basically just take out a little more of the volume, but only a fraction. the exhaust will breathe almost the same as with a straight 3" pipe.

Re: Freeflow exhaust

Posted: 03 Jun 2015 13:29
by JoshJ
sounds like a real TRUCK :layrubber: cant wait for my factory warranty period to expire. then I can do the same. :blonde:

Re: Freeflow exhaust

Posted: 03 Jun 2015 15:39
by davidvdm
Even my 2.7TD runs with a "straight" pipe, and I mean straight :rolling: . After the down pipe and the flex coupling, it is a straight piece of 76mm pipe with one hanger for good measure all the way to the rear bumper:blonde: ...

It was a bit noisy when it came out under the rock slider, and it kept the rear wheel very well lubricated in black soot. I had to remove it when I did the 5" drop boxes for the rear suspension, but I liked the look of the side pipe.. Sorry, that's just the Hillbilly in me coming out.