I know there is a zillion exhaust threads on here but has anyone simply replaced their OEM Headers and Cats downpipe with 200 cell cats (vs stock 700 cell) without changing anything else in the exhaust please?

 

I'm not sure why you would do the headers ($$$$) without also doing the OAP ($$) - especially given the OAP is the major restriction in the entire exhaust chain. Both the headers and rear section are highly optimized with only minimal gains to be had from replacing them.

I know that didn't answer your question directly, but may help explain why hardly anyone is just going to replace the headers without also addressing a far bigger restriction just down the exhaust chain.

 

much more effective for both cost and power increase to do catless OAPs.

 

I'm not sure if this video helps you decide, but they dyno a bunch of different configs:

I feel like if you want to change the headers, then change to equal length headers (without a cat) that flow into a replacement OAP pipe that has a cat where the stock particulate canister is.

 

thank you vm, seems like resonated OAP's are indeed the easiet first step, also as they are simple to fit, but in Europe it will trigger a CEL, so who provides the best blocker for this, software or hardware?

 

You might want to ask on a European forum such as pistonheads or PFF as we don’t have to deal with monitored OAPs in North America.

 

thanks I asked Kline they have a reasonably priced solution

 

So…what is the solution??

 

they have a plug in module which kills CELS at a reasonable cost

 

I see. So you are planning on replacing the stock headers with Kline headers with 200 cell cat? Are you going for the full exhaust - headers, OAP and muffler?

 

as a first step just the OAP's, JCR also has a plug in CEL module