75 Diesel decatting.

Roverron · 7th November 2006, 13:37

Convinced as I am, that a decat will boost the power of my Synergy equipped 75CDT from 148.56bhp to 155 or more, I am embarking on a decat project.

I have ordered a Sebring back box (cat back) and have found a supplier of stainless pipe and reducers so hopefully, attacking the one piece orginal system with a hacksaw and then welding in the decat pipe, should bring about a significant improvement.

When I decatted my 45, it was noticeably more responsive, with much reduced turbo lag, and a good 'free revving' feel to it. I never got around to dyno testing it so can't say what it did to the bhp figure, but the mid range torque was superb. It felt very petrol like.

I've a feeling this will be the case with the 75 - the standard cat and system may be okay for 115 or even 130bhp, but not for 150!

Ron

SCOTTY1 · 7th November 2006, 14:42

That sounds like a top project ron, it's somthing I am concidering myself for next year. Will be intrested in your results

Scotty1

Mike · 7th November 2006, 14:45

Sounds like a good one Ron. Would doing it impact on MOT emissions check at all?

Mike

Roverron · 7th November 2006, 14:57

Quote:

Originally Posted by Mike

Sounds like a good one Ron. Would doing it impact on MOT emissions check at all?

Mike

No, absence of the cat has effect on the smoke test and one is not actually required for the mot.
The exhaust will smell, although using veg oil is one way round this!

Ron

Spanky · 7th November 2006, 17:03

Hmm.... will be very interested in the results of this

andy · 7th November 2006, 17:50

Ah yes -----Veg oil thats a whole new topic !
used to run an old transit on veg oil and white spirit, then the inj. pump gave up, not sure wether it was the 170k miles or ' the mix' that did for it.
Gave up after that as everything else I had would be ££££££££££'s to repair
Andy

Roverron · 7th November 2006, 18:06

Quote:

Originally Posted by andy

Ah yes -----Veg oil thats a whole new topic !
used to run an old transit on veg oil and white spirit, then the inj. pump gave up, not sure wether it was the 170k miles or ' the mix' that did for it.
Gave up after that as everything else I had would be ££££££££££'s to repair
Andy

Apparently Lucas/CAV pumps don't like veg oil but Bosch ones seem ok.
Not sure about Bosch common rail types though, 20,000psi is a lot of pressure so it might be asking a lot of the pump to generate this with something more viscous than derv. At the very least I would run it through a fuel heater and dilute it with derv in cold weather.

Ron

Alex30013k · 7th November 2006, 19:25

Your going to have Green Peace knocking at your door.

I say go for it..

SCOTTY1 · 7th November 2006, 19:53

Quote:

Originally Posted by Roverron

No, absence of the cat has effect on the smoke test and one is not actually required for the mot.
The exhaust will smell, although using veg oil is one way round this!

Ron

Used to run my Mitsubishi 2.8 TD on 50/50 veg oil mix, used to smell like a chip shop from behind. Other than that, the performance was unaffected!

Rincewind · 7th November 2006, 20:00

I need to check this but I think that a cat is required for the MOT as they have been strapped to cars since 1991 and are now mandatory. I could be wrong but reading the stuff that I do a cat must be in place.

I shall confirm (and besides de-catting doesn't really do much for the emission in fact it throws things to the wall with regards emissions limits, CO and CO2 limits as well as the OBD requirements and if the system is worth its salt the MIL will activate as the OBD system is triggered) all of this information but I personally feel that taking a cat off a car is not a clever thing to do.

I know that the strangle the engines performance (they are even worse with a DPF - Diesel Particlate Filter) but they are there for a reason.

I shall check! It's a long and on going debate!

Nic

7th November 2006, 13:37	#1
Roverron Gets stuck in Rover Join Date: Nov 2006 Location: Tarbert Posts: 980 Thanks: 0 Thanked 19 Times in 9 Posts	75 Diesel decatting. Convinced as I am, that a decat will boost the power of my Synergy equipped 75CDT from 148.56bhp to 155 or more, I am embarking on a decat project. I have ordered a Sebring back box (cat back) and have found a supplier of stainless pipe and reducers so hopefully, attacking the one piece orginal system with a hacksaw and then welding in the decat pipe, should bring about a significant improvement. When I decatted my 45, it was noticeably more responsive, with much reduced turbo lag, and a good 'free revving' feel to it. I never got around to dyno testing it so can't say what it did to the bhp figure, but the mid range torque was superb. It felt very petrol like. I've a feeling this will be the case with the 75 - the standard cat and system may be okay for 115 or even 130bhp, but not for 150! Ron

7th November 2006, 14:42	#2
SCOTTY1 Regular poster ROVER 75 CDT CONN SE (MANUAL) Join Date: Nov 2006 Location: Longbridge Posts: 50 Thanks: 0 Thanked 0 Times in 0 Posts	That sounds like a top project ron, it's somthing I am concidering myself for next year. Will be intrested in your results Scotty1 __________________ *Remember, a dog is not just for Christmas, if your lucky you'll have a bit left over for boxing day!* http://www.easyrider01.btinternet.co.uk/ [SIGPIC][/SIGPIC] ROVER 75 CDT CONN SE (MANUAL)

7th November 2006, 14:45	#3
Mike This is my second home Rover 75 V8 Join Date: Oct 2006 Posts: 3,448 Thanks: 0 Thanked 206 Times in 32 Posts	Sounds like a good one Ron. Would doing it impact on MOT emissions check at all? Mike __________________ Mike [SIGPIC][/SIGPIC]

7th November 2006, 20:00	#10
Rincewind Loves to post MINI Cooper S Works (Superchardged not Turbo!) Join Date: Nov 2006 Location: Ashby-de-la-Zouch Posts: 385 Thanks: 9 Thanked 5 Times in 3 Posts	I need to check this but I think that a cat is required for the MOT as they have been strapped to cars since 1991 and are now mandatory. I could be wrong but reading the stuff that I do a cat must be in place. I shall confirm (and besides de-catting doesn't really do much for the emission in fact it throws things to the wall with regards emissions limits, CO and CO2 limits as well as the OBD requirements and if the system is worth its salt the MIL will activate as the OBD system is triggered) all of this information but I personally feel that taking a cat off a car is not a clever thing to do. I know that the strangle the engines performance (they are even worse with a DPF - Diesel Particlate Filter) but they are there for a reason. I shall check! It's a long and on going debate! Nic __________________ Rincewind had been told that death was just like going into another room. *The difference is, when you shout, "Where's my clean socks?", no-one answers* MGR stories, MGR help and advice all available at no extra cost ! The Two Sixties - it's a V8 thing ... Honorary Member and Puddle of V8/4/6cyl Knowledge et al. [SIGPIC][/SIGPIC] Come see who I work for at www.vca.gov.uk without us, the world would be a right mess!

7th November 2006, 17:03	#5
Spanky Gets stuck in Other (Ex ZT owner) Join Date: Nov 2006 Location: Leyland, Lancs Posts: 557 Thanks: 0 Thanked 0 Times in 0 Posts	Hmm.... will be very interested in the results of this

7th November 2006, 17:50	#6
andy Avid contributor ZT-T cdti automatic Join Date: Nov 2006 Location: gloucester Posts: 210 Thanks: 3 Thanked 10 Times in 5 Posts	Ah yes -----Veg oil thats a whole new topic ! used to run an old transit on veg oil and white spirit, then the inj. pump gave up, not sure wether it was the 170k miles or ' the mix' that did for it. Gave up after that as everything else I had would be ££££££££££'s to repair Andy

7th November 2006, 19:25	#8
Alex30013k Posted a thing or two Rover 75 Saloon 2.0 CDTi Conn Se Join Date: Nov 2006 Location: Ashford Kent Posts: 1,560 Thanks: 17 Thanked 29 Times in 21 Posts	Your going to have Green Peace knocking at your door. I say go for it..