Cat Power

[Simon.seven]

Does removing the Catalitic converter increase power much?

 

I have a new R400 Duratec, what is the likley power difference to be if I remove the cat and replace with straight through pipe? Is it worth spending £200 on a straight through system and only getting the cat out for MOTs?

 

 

 

Edited by - simon.seven on 1 Jul 2008 14:10:05

 

Edited by - simon.seven on 1 Jul 2008 15:37:31

[u01rsb]

I don't think it makes a huge difference, and if you are thinking of doing sprints and hillclimbs you will need it for next season.

 

Somebody on here may have a before and after rolling road graph that would have the actual difference on...

[Pat the Plumber]

mines straight through, with no Cat. i just use a Caterham friendly garage for the Mot.

Can't say if it gives more power as it's never had one fitted when i got mine.

 

Duratec is the way forward!! Here

[Simon.seven]

I got the straight through pipe from caterham and fitted, putting the cat on one side not to be touched for 3 years.

 

The noise is totally different, it reminds me of an old bigbore janspeed on a mk2 escourt. Compared to the noise with the cat on it is ten times better.

I am also getting !ft blue flames between gears when thrapping it.

I do not know whether it is faster but it sounds faster, it feels like a different car absolutly fantastic. Any R400 duratec owners this is highly recomended.

 

Ditch the cat, you know it makes sence!

[k80rum]

I'm fairly sure that the catalytic convertor CC use is a large bore 'race' type which probably doesn't reduce power through additional overall back pressure too much (although I'd be interested to see some comparison graphs too). I think the main performance advantage with the bypass pipe is the significant weight saving it gives - the convertor isn't that light in comparison..

 

I must admit I use a bypass pipe and put the cat on for the MOT. I also get a few flames now and again (which I deliberately haven't dialed out because they're fun in a juvenile way, and it's one of the reasons I like the car ) and so I convince myself that as well as a weight saving, by bypass pipe is helping extend the life of my expensive cat when I'm pressing on.

 

Darren E

 

K80RUM Website and Emerald maps library

 

Superlight R #54

 

 

 

Edited by - k80rum on 8 Jul 2008 21:10:20

[Rich N]

Also swapped my cat' for straight through pipe last night, (1800 k-series) and the noise is even deeper now! Can't comment on power because although I have a RR graph, it was done with the straight through pipe on it anyway.

 

My standard Caterham cat' did appear to be made of the less-dense material, same as my 200 cell 'race cat' on my other car in terms of appearance when looking end on, and the amount of light that would pass through it.

 

..but yes, the weight difference is big between them. Just wanted to know how you know you get flames!

[Andy Whittle]

Crispy critters and kiddies on the pavement 😬

 

I am Leg End...

 

Edited by - Andy Whittle on 9 Jul 2008 13:31:28

[Simon.seven]

The first Caterham I ever had a go in was a well tuned crossflow, it cracked banged and spluttered, it had a fantastic induction and exaust noise. This added to the experience of the car. I was quite disappointed with the K series car I got as it did not quite have the soul of the crossflow. It did start and was 100% reliable though.

I now have the new Duratec R400 minus the cat and it is the best of both worlds

Crack bang flaming exaust, on the overrun.

Its fantastic.

I assume the mapping is not perfect and a little rich, I will not be adjusting it though!