Pre-cat removal questions

stubby

Does anyone produce an aftermarket exhaust section to replace the pre cat on the 2.2 engine, that still connects to the standard exhaust.
once the pre cat is removed does this have any effect on the emmissions from the engine.
Does the engine require a modification to the mixture , resulting in the better air flow thro the exhuast or is this taken care of by the standard engine management system settings.
finally is the pre cat different on the 1.8 2.0 and 2.2 litre engines.
I was thinking of buying a pre cat from a scrappers and doing the mods to that one first.

Andy

on the 2.2 there is the pre cat and the main cat. the pre cat sits just inside the downpipe where it joins the manifold then there is the main cat at the end of the section.

you can remover the pre cat and it wont cause you any problems with emissions for mot, mines past 2 no problem. however you can't remove the main cat on the 2.2 as there is a sensor either side of the cat and it will cause you problems.

vocky

as above, no problems with emissions as it's just a pre-cat and the main cat is untouched

the ecu will relearn the parameters once the pre-cat is removed

a very easy and common mod for the z22se

Ffoeg

its a win win situation removing the pre cat - it really serves no purpose other than to control emissions while the mani cat gets up to operating temp (which isn't that long TBH), after that it is just a restriction

I've got a standard front pipe/cat section with pre cat removed for sale if you're interested 😉

Matt

Ffoeg said:
I've got a standard front pipe/cat section with pre cat removed for sale if you're interested 😉

You got the new manifold on then Geoff?

Ffoeg

Do try to keep up Matt 🙂

I've got a Lexmaul one now 😉

blue_se2

has you manifold made any differance Geoff?

Ffoeg

yeah big difference - I'm skint :?

First thing I noticed when I put it on was how restricted it felt, which as never three before - it sort of wanted to go but there was something stopping it. So a quick change to a Blue Flame cat back exhaust and all is well again.

But it's stil not as good as it could be , but hopefully the upcoming remap will be sorting that out and getting all the bits working togther beautifully - time wil tell on that tho

blue_se2

Where you getting your remap geoff?

Ffoeg

Mr Thorne's :smile:, when next I'm down that way, which should be in about a month from now

vocky

Ffoeg said:
Mr Thorne's :smile:, when next I'm down that way, which should be in about a month from now

you coming down to MK notsure.gif