Surprising mot result

[kbee]

My S2 has a piper exhaust 56K miles , sooooo along comes the first MOT after fitting the exhaust , in went the probe and i waited for the comment---nothing was said , the mot continued , then PASSED.
On asking the gentleman said the emissions were perfect, the best he had seen in a while . Am I just lucky or is this normal ?

[MPx]

Depends whats been left in there. Have you got the pre cat eliminator? If not then the exhaust gasses are somewhat strangled right near the manifold. I've got the PCE. Then there was an option of "sports cats" that could be added. I've got one - some had two. With my set up Piper 2.25, PCE, 1 Sports cat, Ported wastegate I just scrape through emmisions with the switcher chip on the standard S2 programme but get nowhere near with the Everest programme.

Whatever, a good emmisions readout suggests a good burn so hopefully yours is going very nicely!

[FunElan]

I've had correspondence with PNM regarding a "Sports cat" and they had never heard of such a thing. This swayed me away from modifying my exhaust. OP, I'm glad you passed!

I'm very nervous to do our emissions test here in California soon. From my research, it's much more strict than your MOTs.

[GeoffSmith]

There appears to be two ways to conduct the test, each with different criteria. What levels did you achieve?

[Simon_P]

My Green S2 passes the straightforward emissions test every time. Standard pre cat etc standard spec. + piper with sports cat. I only had an issue when the engine wasn't hot enough


Anything with a chip or a cat missing has had to go through the look it up method to scrape through.

[kbee]

i have only the pre cat , the 2.25 piper exhaust is from the pre cat back no other cats or restrictions . i have no idea which tests were carried out I assumed the tests were a standard thing

[dapinky]

I know it doesn't help you much, but I got a reading of 0.8% today on my SE .......... so obviously no cats fitted as standard. That is with a closed-loop Everest chip and Piper 2 1/4" exhaust.

Up a bit from last year, but I can't remember what setting I had the chip on when it went in last time.

[Fredjohn]

Likewise. SE, closed loop. Everest chip, 2¼" exhaust (not Piper) no cats.

MOT reading 0.5