hi , im have Renault Megane 3 1.4 Tce Coupe (2010) Model ) just asking if i put Diesel engine on it , do i still have to change computer box , engine code H4j , the one i wanna do conversion with is 2.0DCI M9RG.
as @KingWhiskers has aluded too, there are a few problems you will encounter
1. All the ECU's will have to come with the engine from the donor vehicle
2. You will have a heavier lump up front therefore you will have to improve the suspension at the front end
3. You will have more power, therefore more speed and will therefore need better brakes
4. You will probably have to change the clutch for a dual mass clutch
truly you would be better off buying the car you want with the engine you want and have the manufacturers do all the hard stuff for you
Not saying you should but from someone who has converted from petrol to diesel in the past, you will require a complete doner vehicle, there will be multiple obscure parts that you didn't know you needed so having a complete vehicle will make it whole lot easier then trying to find these parts for sale. With regards to changing v5, If you have a garage do the work dvla will require recite from garage, if you diy it you'll have to get an engineers report. After you've changed your v5 you get issues with insurance and ordering parts as your vehicle will always default to the original petrol. You will also devalue your vehicle, conversions like this are generally frowned upon due to the complications they can throw up. In short would I do it again, f##k no!