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Aldoo

Just after a bit input on decattign a mk2 1.8 tdci focus

 

dont know if anyones looked, but the cat on them is right after a bend out of the engine and then a flexi pipe straight after.  looks totally different to the other ford cats which have decats on ebay :(

 

looks like my going to have to reck the current cat to do this, which obviously im not overly happy about

 

 

iv thought of several options for it but cant settle on a definite one

 

 

 

also, it seems every garage looks at the issue of decat diesels differently, some are fine some arent. the most recent i went to said it was instant fail if they see it missing

 

 

..if i find one happy without having the actual cat and its just off the emisions it also seems like the result will be totally luck. some diesels are fine on suet, others will struggle!

 

 

Any inputs are welcome guys :)  ..have you had on or looked? ..anything! lol

 

Cheers

Aldoo

and the options iv thought are:

 

-hollow the current one

-chop the actual cat out and weld a pipe from the bend

-get a cheapo used cat off ebay to hollow and fit so it looks like theres on there but i still have one i could re-weld

 

..no idea to be honest :(

b1g_dav3

Diesel's aren't required to have a cat, so it wouldn't be an instant failure, however if it's such an issue, get it hollowed out, can probably do that yourself really.

FOCA

Pictures?

Aldoo

should the car pass the sut test without EGR and cat? as if it wouldnt id want to have one to throw on though

 

but emptying my current one is looking probable

i know most people just empty, but would it not allow better pressure and smoother flow to open it to empty and stick a 2.5" pipe through so its not just a box?

 

Thanks for the response

Aldoo

http://www.ebay.co.uk/itm/Ford-Focus-1-8-Tdci-catalytic-converter-/290871342837?_trksid=p2047675.l2557&ssPageName=STRK%3AMEWAX%3AIT&nma=true&si=NCCKT08i7%252B1dBwbb1LyQz7Nc0Mo%253D&orig_cvip=true&rt=nc

 

and thats the sort it is

..seen a lot of search results and read up a lot about your car FOCA, sounds great! :D

 

cheers

stef123
I believe that diesels will now fail an mot for not having a cat fitted although they are not required for emissions test.. Might be worth just double checking though

Just double checked this myself with the mot testing regulations, removing the cat on a diesel is still legal. (Section 7)

January 2012 mot changes confusion I think lol
Mike77
As above, I'm sure if the car was built with one, it must be present, visually anyway.....
FOCA

There was a great deal of confusion over the (Jan 2012) changes in the MOT even the testers were confused and required "clarification", and the amendments looked like a "u- turn" to me

 

it may be as time goes on the changes are phased in/ the MOT tightened up, things that were "advisory" may become "compulsory" in the future and the test becomes tighter

 

the official line is that it is to make the UK more in line with the EU - but my "gut feeling" is its to force older cars off the road (as the MOT gets tougher it becomes more and more difficult (and expensive) to MOT your old car there will be a point where it is more cost- effective to just buy a newer car)   

 

I thought i needed a catalytic converter on my diesel car (late 2011), i was running a stainless steel decat,(2-1/2") heatwrapped, and heatwrapped downpipe, straight- through exhaust with "straight through" middle silencer, (the silencer is in the middle for better traction & handling balance compared to having it behind the rear wheels on a FWD car)  and the back box deleted (replaced with unsilenced pipe) (all 2-14" apart from the decat)

 

its a mk3 Mondeo deisel

 

I had a EGR delete and a tuning box (i took the tuning box off and reset the ECU for the MOT though)

 

The car sailed through the MOT (and emmisions - really clean exhaust output) in 2012 i spoke at length to the tester and he said the decat was no problem - only the particulates are measured - there are covers on top of the engine, a heatshield on top of the cat/ decat (but you can see it if you look hard enough and know where to look) and an undertray under the engine, Testers are not allowed to remove covers

 

The car was a bit louder than stock - but that was not a problem either (testers discretion?) 

 

in 2013 i thought i may have a problem but again, the decat was ok , failed on windscreen and rear middle ceatbelt (i never use it so i removed it to save weight, along with a few other things) the tester seemed quite impressed with the car - i "picked his brains" and asked a lot of questions, he suggested i just take the back seats out, a brand new windscreen later (heated - don't ask the cost (ouch!)) and missing its back seat i got my MOT certificate in my grubby paws - the back sats weighed a ton (27kgs) so it was just the excuse i needed to leave them out and strip out the back of the car, black out the windows and convert it into a van - with all the lightweight parts and stripping it took it down to a healthy minus 150kgs

 

Aldoo, - technically the best thing is to cut off the cat, and weld a straight bit of pipe in its place, the same diameter as the pipes with no steps or bumps, if you leave the cat on even with the insides not in, you will lose velocity (flow/ power) but it would be better than having a full cat, though   

 

I can't remember if it was my idea, but you could build up a lot of heatwrap in a fat "roll" untill the decat/ straight pipe looked like a cat that had been heatwrapped, from the outside, if you know what i mean (i was planning this, but it turned out i did not need to) 

 

Thanks about the comment about my car - ive not done much to it recently scince the 3rd superchips remap and the electric waterpump - ive got a load of plans for the summer/ when the waeather warms up a bit (if it ever does :) )    

Aldoo
That's a good idea with the layering the heat wrap ..i guess even if they know its got no cat they can't do anything!

And where did you guys get info on the mot rules? Is there an official direct gov site or anything? Everything iv found seems to just be peoples interpretations of it


The rules are over the top now though. They test things that are totally irrelevant! I looked at old mot certificates when i got mine, it had an advisory because the childseat was on the back seat!!

Cheers guys
stef123

That's a good idea with the layering the heat wrap ..i guess even if they know its got no cat they can't do anything!
And where did you guys get info on the mot rules? Is there an official direct gov site or anything? Everything iv found seems to just be peoples interpretations of it
The rules are over the top now though. They test things that are totally irrelevant! I looked at old mot certificates when i got mine, it had an advisory because the childseat was on the back seat!!
Cheers guys

Yes but was part of the advisory because they couldn't test the seat belt?

http://www.motinfo.gov.uk/htdocs/index.htm
Aldoo
No idea ..possibly, will removing that be the same as removing engine covers?
stef123

No idea ..possibly, will removing that be the same as removing engine covers?


Not quite sure I know what you mean?
FOCA

That's a good idea with the layering the heat wrap ..i guess even if they know its got no cat they can't do anything!

And where did you guys get info on the mot rules? Is there an official direct gov site or anything? Everything iv found seems to just be peoples interpretations of it


The rules are over the top now though. They test things that are totally irrelevant! I looked at old mot certificates when i got mine, it had an advisory because the childseat was on the back seat!!

Cheers guys

 

I agree, is a bit "jobsworth" with some silly rules that are nothing to do with safety - the baby seat seems like that

 

I studied the new rules (in late 2011) and was convinced a catalytic converter was nesessary from 2012 on a diesel, suits me fine that it is not (its difficult to interpret the rules) - they may get tougher and an advisory this year may become a compulsory next year - the blue warning light for main beam, and the EML / warning lighs is in that catigory  

 

(a catalytic converter is nessesary on a petrol engined car  of course, if anyone is reading this, decats are for diesels/ off road petrols - even a rally petrol car has a cat now )

 

Often, a garage that does repairs can sometimes do MOTs too,  if you get them to do some of the work - they can be very helpful, some seem to have a more positive attitude towards modified cars  

Aldoo

had a chance to read the rules now im home. It appears that a cat is needed on diesels as well and and also they are allowed to remove covers :wacko:

..i think you lot with decats have good relationships with your garages? lol

FOCA

had a chance to read the rules now im home. It appears that a cat is needed on diesels as well and and also they are allowed to remove covers :wacko:

..i think you lot with decats have good relationships with your garages? lol

It does seem like that but trust me - its not - 100s of decats are sold in the UK each year for diesels i MOTd my car 3 times with the decat fitted, 3 different testers, 3 different places including Halfords, and Quick-fit

 

They were not allowed to remove covers before, so if they can now - its new

 

Im getting my car rolling road/ dyno tested soon, the place also sells performance parts and remaps, and does MOTs (its a "performance centre") it preps race / rally cars too

 

The guy that does the MOTs (never had my car MOTd there - yet) builds/ modifies  cars and has a NIssan GTR with 600+ HP, stripped out and road legal he is a member of a serious modified / racing car club/ forum (all makes) that i happen to be on too, i have already been in lengthy discussions with him about issues like decats / the new rules etc, he has written several articles about the MOT rules and the significance of them to modified cars  

 

I also talked at length with each of the 3 different (other) MOT testers obout decats/ next years MOT etc

 

As well as this i discussed at length the fitment of decats to the editor of one of the worlds leading Ford magazines, who is a lobby-ist (pro - modified Ford cars) who has been in contact with VOSA, the government and industry leaders

 

If you have specific questions, anything about MOTs(present or future), i can find out for you - if you read the VOSA site, it will only be your interpretation of it, - which may be wrong  

 

I think the "you lot" comment says a lot - like a "them and us" attitude -  you are part of this forum too    

Aldoo

certainly a lot of reliable and reassuring info there!

Think I'll be going for it in the next week or so now

 

then full service and a remap should have it going like a whole new car! :D

 

 

and sorry if the 'you lot' came across bad, i didnt mean anything by it and i am really happy with the info im getting from being on this forum and now trying to help others where i can :)

 

Cheers

FOCA

No worries, its "us lot", now :lol: - With you bieng a Ford owner/ enthusiast & forum member  - soon to have "serious" modifications

 

You should do a build thread, with a before/ after & pictures, even get the car dyno-ed

 

There would probaby be a lot of interest  :)

b1g_dav3

If you want to ninja decat, get a broom handle through the cat and belt the innards out :P Or buy a scrappy one and do it.

Aldoo

I will soon be making a build thread yeh.

one thing ill try make a guide for is vanity lighting. the GF was saying about having lights in the mirror so i got those sorted.

i dont know how people take pictures of their progress though, i got too engrossed and just forgot about pictures!! haha

 

still looking at options for the cat. im liking the idea of hiding it with heat wrap, i would love to smash my cat, but theyre expensive so seems a real waste!

 

the current plan is:

decat

service inc fitting a better air filter (read a lot about Green Cotton)

and then a remap, likely a custom one with a dyno :)

 

Tom

FOCA

Nice one! -

 

If you have your camera/ phone handy when you are doing the work and take a snapsot at intervals - there can't be many (if any) that have de-datted your tipe of car that way (and done a guide/ build thread too) - you might be the 1st one, with many following what you do - so its worth taking pictures, you can do the words after  

 

if you cut the cat part out cleanly with a hacksaw/ grinder, you could sell it on for others to reweld - i dont think you could get into it with a broom handle - too many bends! (ive heard of this with metal spikes, but on cats with straight in/ out pipes you can "get at") 

 

if you have to smash/ cut the cat, a scrap metal merchant may still want/ pay for  the insides, as it contains preciuos metals like platinum  

Aldoo

i think ill be doing a cut off and straight through pipe. then either sell the cat or keep it for if i come to sell in future (but as an immature 'in the moment' type of guy i guess ill be selling! haha)

 

would you recommend taking the cat and flexi pipe off or just the cat?

 

ill remember to do pics though :) ..i couldnt find anything when i was looking for previous people who've done it

FOCA

I would just replace the cat with the straight pipe, so the flexi goes back on the car (save you having to make one)  

 

The pipe has to line up so the downpipe/ flexi all sits in the same place as before (angles/ distances) - so has to be measured up accurately   

Aldoo

when this snow goes (AGAIN!) ill have a look at whats involved. id assume the in and out of the cat will be a striaght line so that should be easier.

but for all i know it will be seized beyond me being able to get it off, so ill get a price of a local exhaust place to do the whole job for me.

 

i went in asking for info and he told me £35 to put a straight piece over the cat, but id guess thats just him welding it and id have to take it appart for him

Aldoo
Now armed with more information ..and it hasn't helped at all!!

Been speaking to (deep breath!) my friends,girlfriends,dad. Who has been a ford master mechanic for nearly 20 years.

He's been saying the 1.8 tdcis are bullet proof engines as they are. But they have old style big heavy pistons and inners which apparently don't like extra power.
As far as he cares decatting and the air filter will make next to no difference but just help blow it up.

He does say that the 2.0 models have a massive amount of potential though!


..hate having so much to think about!! ..i don't know whether to go for it and just have a laugh till it blows or be safe :/
FOCA

Now armed with more information ..and it hasn't helped at all!!

Been speaking to (deep breath!) my friends,girlfriends,dad. Who has been a ford master mechanic for nearly 20 years.

He's been saying the 1.8 tdcis are bullet proof engines as they are. But they have old style big heavy pistons and inners which apparently don't like extra power.
As far as he cares decatting and the air filter will make next to no difference but just help blow it up.

He does say that the 2.0 models have a massive amount of potential though!


..hate having so much to think about!! ..i don't know whether to go for it and just have a laugh till it blows or be safe :/

Well, you girlfrends dad might be right  but, a master mechanic is more involved in repairing stock engines and cars - power tuning is a specialized subject,  

 

A 2.0L is probably a better starting point, but as you already have a 1.8, and if you can get the welding done for £35 and you might even make a profit on your old cat its not going to cost the earth

 

Also, as you go through the process of researching, discussing, working on your modifications/ getting work done, you are learning more about cars/ engines/ tuning all the time, there are significant engineering challenges, a good mechanic is not nessisarily a good  tuner (some are) - it involves thinking "out of the box"

 

The cat is "passive" (it has no lambda sensors on it like a modern petrol engine) - it can be removed and will not make the engine run lean, the loss of back-pressure will not loose power just make the turbine spin up quicker

 

If you make a bad job of the decat you might have lumps of weld sticking into and restricring the gas- flow, or it leaks or it does not fit or it snaps in half - none of those things could "kill" an engine

 

Likewise modifications to the inlet, (pre compressor, retaining some sort of effective filter), you cannot melt plugs etc or run lean like a petrol car

 

Probably the worst thing that could happen with the decat / inlet mods is there was no improvement in power - the chances of it damaging the engine is slim - if you were revving it very high in the lower gears you could drop a valve or throw a rod, - but you would need to rev it way past the redline to do that

 

I hear "i will never work" all the time when i fitted my (replacement for DMF) solid flywheel carbon fiber/ kevlar flywheel I was told it would shake my teeth out, bend the crank and "last 5 minites" 2 years later its still perfect (i doubt a DMF would have survived me/ my car)

 

I bought a DTUK tuning box (rrp £399) (bought secondhand /never paid that for it! ) if you read many posts on forums these are just £1 resistors in fancy boxes, and all they do is fool the ECU into making the injectors squirt more fuel in and those injectors won't last long Well. i had the tuning box for years, it had a programmable digital microprossesor in it, i modified it so it had a remote dial to turn it up/ down, i then adjusted it for maximum power by doing timed runs - so the car had optimal acceleration regardless of the amount of smoke/ stress on the injectors pump etc - its lasted years , still original injectors (switched to bluefin now though)

 

There was someone drag racing a Mk1 Mondeo with the old 1.8L 8v TD lump in - it was very quick (14 sec standing quarter , quicker than an st220,  as far as i remember)             

Aldoo

FOCA, you're a very reassuring man/im very easy to persuade!! haha

 

I think ill be having a new timing belt fitted by a mechanic whilst this weather is bad, then ill look to do the work once the snow realises its nearly april!!

 

I mentioned the green cotton air filter and also said that the intakes and filters on them are about as good as they can be. claimed theres next to no difference even without a filter.

 

 

...im thinking after reading about that the mods will all make tiny differences, but i guess itll add up. plus its just something to keep me occupied isnt it! haha

He will be right that it will likely shorten engine life, even if its just due to me wanting to push it further. but i guess thats something ill address if it actually happens.

 

 

one last thing. would you just go for same width as current pipe or have a diff size for the decat section? ..the most common iv read is that 2.5 inch is best.

 

Thanks a lot for sharing the knowledge!! :)

Tom

FOCA

No worries :)

 

I use a 2.5" decat, but there is a step in the pipe down to 2-1/4" and the exhaust/ cat is a different design from yours 

 

for you, you would be better with the same size pipe as either side of the cat - so it stays the same diameter with no step up or step down, if you are going for a bigger diameter, it needs to be the whole length - from manifold to tailpipe, otherwise its a waste of time

 

2.5" is not best if it is smaller either side - its got to be a smooth flow with no "steps" - so if its 57mm on either side of the cat, a 57mm decat would be best

 

Some people say if you have more power you don't have to "thrash" your engine so hard - so a tuned motor is put under LESS stress - i suppose it depends how you drive it :)    

Aldoo

right then, so ill just continue the same diameter as it is going in and coming out of the cat :) ..next time i have the car up ill have a look if the pipe is the same diameter the entire length

 

and yeh, they say the engine wont be laboring as much so its better on fuel, but thats assuming you still drive at the same speed

 

 

as you said though, this is a learning experience, im only 19!

after a few years more N/C and me getting bored of the 1.8tdci ill probs have a 2.0. and i should know exactly what i want to do with it! :)

 

Cheers



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