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what size exhaust for 4BD1 tubo

Posted: Wed Aug 16, 2006 5:32 pm
by def90
did a search can't find answer.

currently running non-mandrel 2 1/2" on my 90 and looking at maybe 3" mandrel?

truck is as stated - defender 90, intercooled turbo running 12-14 PSI

Re: what size exhaust for 4BD1 tubo

Posted: Wed Aug 16, 2006 5:35 pm
by Micka
def90 wrote:did a search can't find answer.

currently running non-mandrel 2 1/2" on my 90 and looking at maybe 3" mandrel?

truck is as stated - defender 90, intercooled turbo running 12-14 PSI
What? :shock:

You don't trust my opinion? :cry:

exhaust

Posted: Wed Aug 16, 2006 6:00 pm
by def90
go and do some work mick :D

nah, i've already made my mind up bud just curious on thoughts...if 2.5L 4cylinder can sound that good, surely a 3.9 can sound better :twisted:

main reason why i wouldn't get it done is if i can't get the dump pipe enlarged, or if its gunna be too much $

Posted: Wed Aug 16, 2006 7:53 pm
by Micka
Ahh...excuse me?...

Its a 5 cylinder, thank you :roll: :finger:

I will give Steve from Brisbane Exhaust a call tomorrow to suss out a price for you mate.

Posted: Wed Aug 16, 2006 8:48 pm
by ISUZUROVER
3" would work well Sam, I will be doing the same on the 110 when I get back to OZ and fit the turbo (can you ask your mate to start looking for a T25...). I am not convinced that mandrel bent exhausts are worth the extra money, If I have some spare time I will run a simulation in fluent (used for modelling flow in exhausts and other things) and see what the actual difference is. 3.25" press bent may be just as good as 3" mandrel...

Can anyone give me any info on how much the pipe is squashed by the press for the simulation???

Posted: Thu Aug 17, 2006 12:17 am
by "CANADA"
Would a T25 be sufficient for the Isuzu?

exhaust

Posted: Thu Aug 17, 2006 7:08 pm
by def90
ahh bugger forgot about that other 'cylinder', anyways cheers mick, i'll wait for ya reply.

no worries ben i'll call him t'moz.

the small turbo works fairly well on my old girl.

Posted: Thu Aug 17, 2006 7:31 pm
by ISUZUROVER
MADZUKI wrote:Would a T25 be sufficient for the Isuzu?
As Sam said above...

Also a 4L diesel that redlines at 3000rpm needs to move the same amount of air as a 2L engine that redlines at 6000.