a.f.a.i.k the test done to a c.a.t. would be to measure it's temp ..
is the emissions test for a diesel not just about smoke particles emmited ?
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anyhow .. i kept the c.a.t. intact and fitted a straight thru backbox ( stainless.s )
works fine .. as in .. a tad better response from lower rpm .. sounds good as well
well do take a look at :
https://www.landyzone.co.uk/land-rover/intercooler-problem-mod.126484/
( pics on page1 are a bit blurred for some reason ..
( be clearer pics on page 2
i.e. the quicker the air flows across the maf. sensor ..
the quicker the engine will respond to go-pedal input
particularly from the lower rpm range
( the main drive-abilty issue with the td4/m47r in stock format .. i.m.h.o. )
adding some heat insulation to the air intake .. negates the engine bay heat soak effect ..
i.e. 'cause the heat be registered with the air temp sensor .. and reduces fuel input ..
resulting in potential sluggish response until cooling air enters and drives away built up heat
.. the egr delete-mod would be part of that a.i. modification ..
then .. with the added torque at the lower rpm ..
consider adding
slightly larger tyres to raise the gearing a bit
( unless you go off-road .. might be detrimental in that case )
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