Something I'll be looking to do in the future.
I've read that it makes quite a bit of difference.
I found with my PD140 that just the decat pipe (staying OEM size) didn't give any increase in power but smoothed the power delivery out and also gives a nice little whistle
.
Would I do it again? if having a remap then No, unless I'm replacing the whole system replaced or the CAT failed.
(ignore the numbers, They are very optimistic with vcds logging.) All runs were done after fitting each component on the same stretch of road on the same day.
However, on my old PD130 I had a Turbo back Miltek system (De-cat/resonated) fitted, the exhaust gave 11bhp more and gave me another 23ftlb
, that was running a generic Jabba remap and it wasn't altered after the exhaust was fitted.
Matthew