you have to wonder why anyone would come up with a hair brain idea like that.
Well it only takes 1 to come up with the idea and if he is a good enough salesman well the world will buy it (plenty of examples there).
I followed earlier threads on this site for quite some time before investing in a Chipit and DPF delete pipe.
There was some improvement but not across the whole range of revs etc.
I wanted an improvement for towing but didn't even get to try it.
After the Nav went into limp mode and belched black smoke I contacted Robert who sent me the blanking part. I'm no engineer but I understand safety and limitations etc (had the replacement part been of the nature of a pressure release valve with slightly more resistance that could still have been within the safety limits of the fuel rails I could have been conned further).
That was the end for Robert couldn't come up with any other suggestions and refered me to Chipit W.A.
Tried several retunes with no result.
As I was due to go on holidays I took the Nav to a Diesel serciving specialist.
The outcomes:
Dynotuned the Nav with and without the DPF delete pipe.
Less HP with the Delete Pipe fitted.
No fault with the pressure release valve fitting.
There was another fault which was corrected.
There was a post on this thread or a similar thread where Robert insisted that if anyone had a problem and was dissatisfied that Chipit would make a full refund.
Well that was not to be the case.
My suggestion
I tow a 2.8 tonne off road caravan and a 2 tonne trailer sailer. My Nav pulls both quite comfortably, uses more fuel sure but still uses less than most when not towing so it still comes in as a cheaper tug.
Safe your money and put it into more fuel it will still work out cheaper.
I mainly use my Nav for towing and have done around 30,000 towing K's out of 70000k's and have only just done my first DPF regeneration that took place while I was pulled up reading my manuel on what to do after the light came on.
It's all a lot of hype
Cheers All