Hi all Just got my cat back Stainless exhaust delivered today and put a bid on ebay for a de cat pipe, for after the mot. what are the advatages and disadvantages of the de cat. I will keep the original cat for the next mot. does a de cat mess up the ecu and put it in a limp mode ? does it mess with the oil seal on the turbo ? what power gains might i expect ? what would happen if i was pulled over with no cat? have you had one and changed it back to the cat. thank you.
There are no con's to having one tbh apart from its illegal but no police officer is going to pull you over and get on the ground to check. People say that the lack of back pressure causes the turbo seals to weep this is a load of cr*p the turbo creates its own back pressure. You should see some power gains as the turbo can spool up quicker and should give you a little more top end power.
The forum is awash with people who have put a decat on and had their turbo go within a short period of time afterwards. This example sticks in my mind. There are people who've fitted them with no ill affects, but it's a lottery.
If your car has a newer turbo with staggered seals then they are much more robust and can withstand the drop in backpressure caused by fitting a decat.
