PRE Cat help

Daniel

hey i new to the site and looks like a great site to be involed in !! em i jw is it worth takin the pre cat ou ??? any gains?? plus i been told it might pass mot is this true any help would be great thanks???? Dan
😃

MikeS

the pre cat is there to help warm the cat up quicker on cold starts, also i reckon it helps the exhaust components with back pressure

Daniel

so would you say it not a good thing taking it out then m8 ???

vocky

the precat is not required, it has to be fitted at first registration, then it's not required

it robs between 3 - 8 bhp, so my advice is remove it asap :lol:

ps: I have had my z22se engined cars pass 6 mot's without a precat in them, it doesn't effect the emissions at all.

Daniel

nice 1 m8 just finished seems all good cheers

kinglarry001

hey, new to this site, am loving the info.

but one quick thing about the removal of the precat. i was thinking about removing it, but spoke to a couple of mechanics, and they both said that if you remove it, it will cause problems to the engine. will mess up with the sensors or something.

im no mechanic, so unsure. i can only go on what people say. and on this website and vvoc, people say its good. but the two mechanics say other wise.

have you had any running issues with the precat removed?

cheers jake

MikeS

what they probably mean is if you DIY and cause a problem on anything without realising that it is gonna cause you hassle and might be expensive

Daniel

i mean i done myn and runs fine i was worried too and was told it may not be the best thing to do but i seen no problems works fine and if anything it a bit more faster plus makes car sound much better

JohnnyN

As long as you don't damage the sensors in the downpipe or use WD-40 on them if you need to remove them then everything will be fine. Also, keep the precat end of the pipe angled slightly downward when drilling out the precat or when you are chiseling it out. This will stop any of the broken particals falling into the main cat causing a blockage.

Stick to all the above and it'll be all fine an dandy!

thumbup

kinglarry001

are the senors near it then?
is the only way to drill/chisel the inside of it out? cant you cut it out completely and replace with a bit of pipe?

JohnnyN

The precat sits in what's called a collector that attaches to the manifold. Unless you can replicate that then you must remove the precat by means of a drill or chisel. I used both.

The sensor sits about 6 inches below the precat. You don't need to take out the sensor.

Sjdickso

Just think about this also, if it was required how come newer models mostly after 2003 wasnt even fitted with a pre-cat.

blue_se2

Most cars on here have been decatted and no reported problems mines been done about 2 years and passes MOT's fine

Daniel

isit true the stuff ya smash out is worth money ??? bit random i no but i was told 2day that ppl where stealin ppls cats just for the stuff inside lol ???? and idears

MikeS

out of the cat some metals are worth money

out of the pre cat it is worth nothing

Daniel

lol oh well worth a try