Cat Bypass for lotus elise s1

[kingjon]

hi,

on my last service, the guys at williams lotus bristol told me i should spend 700 quid on a new catalytic converter....

no thanks i said (thinking why not get one off the web and fit it myself?)

so i was wondering what you guys thought? should i do this or should i fit a bypass pipe? will it still pass the MOT with a cat bypass?

would be grateful for your thoughts!!

[Davey S1]

No it wont pass the MOT (unless you can find a friendly place that will overlook it)

Have a look for a second hand cat.

[paulwakinshaw]

car won't pass the MOT test without a cat, its that simple, don't let anyone tell you otherwise. i have seen before and after results with a cat-bypass and a cat and the results are wildly different.

but, the good news is that fitting a by-pass will make the car sound much better and free's up 2bhp approx. swapping the two pieces around come MOT time is a piece of cake too, only takes 45 mins each way.

Wako

[andysv]

im sure hangar 111 have janspeed free flow cats for under £300. and cat bypass for £50ish. not sure what cars they fit.

[Rik A]

You already drive a car that's low on CO2 emissions, thanks to its performance through light weight philosophy. Why F it up and dump a load of CO, Hydrocarbons and NOx into the atmosphere for a measly 2 Hp?

So please, no de-cat. The free flow cat is an option, but expensive for such a small improvement.

If you want a better noise, an induction kit is the way to go. And teh best value for muney performance improvement is a performance driving course.

[rant mode off]

[kingjon]

there there Rik A... Calm down.

thanks for your thoughts guys, confirmed what i already thought but always good to ask the people in the know!

jon out.

[S Works]

Rik A said:

You already drive a car that's low on CO2 emissions, thanks to its performance through light weight philosophy.

In which case Rik, why stick heavy stickers all over it and add more weight than necessary then eh? Eh?

[dss123]

Rik said:

A Why F it up and dump a load of CO, Hydrocarbons and NOx into the atmosphere for a measly 2 Hp?

Just to add some balance to this argument.

We are all petrol heads here, otherwise we wouldn't be driving Elises.

However to suggest that fitting a CRP is killing the planet is, how should I say.......questionable!

These are the facts.

Water vapour represents the earth's most significant greenhouse gas, accounting for about 95% of Earth's greenhouse effect. Yes, that's water vapour, not C02!

Water vapor is 99.999% of natural origin. Other atmospheric greenhouse gases, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and miscellaneous other gases (CFC's, etc.), are also mostly of natural origin.

Human activites contribute slightly to greenhouse gas concentrations (0.28%, if water vapor is taken into account) through farming, manufacturing, power generation, and transportation. However, these emissions are so dwarfed in comparison to emissions from natural sources we can do nothing about, that even the most costly efforts to limit human emissions would have a very small, perhaps undetectable, effect on global climate.

So Jon, go for it mate. A CRP equipped Liz sounds the business. I'm not even bothered about power increases (the VVC doesn't benefit anyway). Come MOT time when I have to refit the cat, my Liz sounds like a sewing machine, even with induction kit.

It's all about having fun and you can certainly sleep well in your bed knowing that your actions will be having no effect on the future of our planet!


Dunc




>> Edited by dss123 on Thursday 23 June 14:15

[cuzza]

I'd like to know where those 'nuggets' of info came from.

I'd just stick a high flow sport cat on it and be done with it. You get most of the CRP benefit in the sound but none of the skinned knuckle hassle of replacing the CAT once a year.

[135sport]

Its not just the noise.

A cat is heavy in comparison to the CRP.

Swapping at mot time is no real hassle.

[dss123]

Cuzza,

It's all out there mate, you just need to listen to scientists that deal with facts and not the politicians and spin doctors.

I can't believe the crap they try and sell.

Speed cameras save lives by the way .... oh don't get me started. Teach people to drive properly and make the driving test relevant - oh no, slipping into rant mode my self now!

Night night

Dunc

[cuzza]

135sport said:

Its not just the noise. A cat is heavy in comparison to the CRP. Swapping at mot time is no real hassle.

Are you having a laugh? I suppose you have a CF can on you Hurricane because that's half a gram lighter too? Can we get a little perspective here please?

Depends on your definition of hassle really. If putting the car on ramps, removing the undertray, undoing the bolts, one of which has probably seized, getting rust in your eyes, digging the CAT out having made sure you don't knock it about and damage it during the year, then going to the MOT station, having it tested, hopefully passing then coming home and doing the above in reverse isn't hassle then be my guest. All that for a bit of extra noise that would make your car borderline at some trackdays (probably a fail at Goodwood) for noise and also makes it "technically" illegal.

Dunc, not saying I don't believe you, I'd be interested in finding out where that info came from and having a read myself.

[dss123]

cuzza,

Here you go mate.

Makes interesting reading.

www.geocraft.com/WVFossils/greenhouse_data.html


Think I'll start a new thread with that one.


Duncs