Custom Exhaust Fabrication 4200 CC

[jasst]

You have to have a cat between the front and rear lambdas , so they have a before and after location so that the brains can work out if the cat is doing its job. So if you remove the front cat, you have to move the second lambda to after the remaining cat, or you will get a CEL.

 

[jasst]

I have been told that if it is reset the CEL shouldn’t reappear

Oh yes it does!

 

[CatmanV2]

Oh yes it does!

Oh no it doesn't!

(Is it Christmas already?)
C

 

[Zep]

Oh yes it does!

Precisely!

 

[Corranga]

Ok, so step 1 remains to check for sure that the cats are breaking up, with an endoscopy camera via the Lambda holes in the first instance.

If the fronts are, then they are obviously better out than in, so remove exhaust and gut front cats.
This then leaves the car in a slightly crazy state of having cats (the rear ones) but also a CEL since the 2 sets of lambdas basically ignore the rear cats anyway.
Will the CEL cause running / performance issues? Will it underfuel or similar?

Will it run ok with a CEL?
No custom exhaust manufacturers in my area, so I'd be looking to drive it to one if that were the route to take, but the closest to me seems to have mixed reviews which is offputting.
Larini is looking more and more like the obvious option, though convincing the wife on the spend is another story.

I guess the other option is to chop the original 2nd cat sections off of the exhaust and bracket in a pair of sports cats with lambda sensor holes on the other side, providing I can get them in the right length / diameter.

 

[Zep]

You can purchase lambda bosses and have them welded into your exhaust in the right place. You can also get plugs for the existing holes rather than remove them. This would only need a good welder rather than a exhaust builder.

 

[jasst]

I guess the other option is to chop the original 2nd cat sections off of the exhaust and bracket in a pair of sports cats with lambda sensor holes on the other side, providing I can get them in the right length / diameter.

This is exactly the route I am taking, when I can find the time to get down to my exhaust fabricator, he is concerned that the cats they use will be too long, so I have come up with these https://www.ebay.co.uk/itm/Universa...0-Cell-Rnd-4-x-8-Magnaflow-59976/183747452614 which according to the supplier are rated for 350bhp each, and already have an angled exit so requiring less fabrication.

 

[jasst]

Will it run ok with a CEL?

Mine does

 

[jasst]

Actually had a brief lull in work commitments today so have just been down to Top Gear (my local exhaust place) and car is booked in for next Tues to have necessary works to cats done, #excited.

 

[Corranga]

Actually had a brief lull in work commitments today so have just been down to Top Gear (my local exhaust place) and car is booked in for next Tues to have necessary works to cats done, #excited.

Oh, please report back, with pics if possible. Mine is going into my local indy for investigation work next Wed to see if the cat is infact breaking up, or to otherwise investigate the lack of performance, which only seems to be when it's hot, which is leading to me thinking the cat has broken up and rotated in the pipe / expanding when hot, as happened to my Elise some years back.

 

[jasst]

She's back, and the 'H' pipe from mlc arrived this morning, so I ran it down there just as he had about finished, but he said he would fit it, to save me crawling around on my back under a couple of ramps, very pleased