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Does any one know what improvement the removal of the two cats on the 75 Diesel will have regarding performance and MOT standards?



I plan to chip, but thought should have this done first to get the chip balanced correctly when done, rather than go back after I get a section made.

Cheers
 

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I don't think diesels require a cat for MOTs as they are smoke tested, not emission tested.

Gains from cat removals is hit and miss, some say good, others no difference, depends on the engine. Smaller engines tend to benefit less. Some cats are more restrictive than others. Only real way is to test it yourself. :D

I found my coupe turbo 'revved' better at the top end without the cat.
 

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Dave turbo said:
I don't think diesels require a cat for MOTs as they are smoke tested, not emission tested.

Gains from cat removals is hit and miss, some say good, others no difference, depends on the engine. Smaller engines tend to benefit less. Some cats are more restrictive than others. Only real way is to test it yourself. :D

I found my coupe turbo 'revved' better at the top end without the cat.
Although the car is legally supposed to have a cat, the smoke test is the only emission test and the cat seems to have little impact on this.

My 45 TD passed its MOT with flying colours despite having an empty catalyst.
I would probably recommend chiseling out the innards so it looks like you've a cat(s) fitted. Though the 'orrible diesel smell is a big giveaway!

I found removing it improved the throttle response and gave a free revving feel. Th turbo came on song a bit earlier too.
On the downside it was a bit boomier above 80.
 
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