[JDV]

To all the knowlegable people please ?

My Pajero DID 2005 were stolen in Jan 2009 and been recovered by the Police a couple of weeks ago:

What damage could be done to the engine and drivetrain that I would not pic up immediatly?

Secondly, If they did not have it service(which is the obvious!), what damage can that do to the engine in the long run?

[4ePikanini]

Only thing to do is to a full service ASAP and take a sample of the old oil for analysis that can pick up brooding problems.

[JDV]

Hi 4eP
Thanks
What do you know about the SAC Plug & Play?

JDV

[4ePikanini]

It is a very debatable subject with regards to chipping diesels.

IMHO the only way to increase a diesel engine's power is to add more diesel. That in turn raises the EGT ( Exhaust gas temperature ) which can lead to headgasket failure and in some cases a cracked head.

I would leave the DiD with the standard ECU mapping as it is. If you want to do any mods at all I would look at making the intake and exhaust flow better and try to get cooler air into the intake.

[JDV]

Thanks;

And your advice on how to do that?

Is it possible to 'move' up the power curve up or down the rpm range on a diesel as they sugest?

[HBannink]

One of the reasons for regular service is the cleaning effect of the oil. If not changed regularly the oil can leave a sludge deposit that sticks to the side of the engine internals. In a worst case scenario the sludge can be loosened by the new oil and block the filter leading to bearing failure. That is a worst case scenario and does not happen overnight, depending on the amount of km traveled it might be a good idea to do a quicker oil and filter change for the next one. As for the rest no major damage should have occurred.

God to hear you have your baby back

[4ePikanini]

Thanks;

And your advice on how to do that?

Is it possible to 'move' up the power curve up or down the rpm range on a diesel as they sugest?

Torque is determined by many things

Cam profile
Crank profile
Compression
Displacement
Bore Stroke
Fuel ratio
Intake flow/restriction
Exhaust flow/restriction

Finding a good balance between all of these at various rpm's ( depending on design these traits vary strangely and considerably at various rpm's ) is a very complicated science and best left to the professionals with diagnostic equipment.

The easiest for intake is to make sure you get air from outside with as little as possible bends but beware where you pick up your air from as a big puddle can splash into an ill located intake.

The easiest to get the exhaust improved is to fit a larger exhaust with a less restrictive silencer and some custom headers ( exhast manifolds that consists of individual pipes )

The DiD is a monster and very well designed and set up from the get go. I would recommend leaving it as is because any alteration will cost a lot with little gains at a time.

Just make sure your intercooler is free of any debris as that is cheap to do and the difference in power from a intercooler, that works as intended as opposed to one that is not working to potential, will be enormous.

[JDV]

Thanks for the info

I am confused about a couple of things you said : like a crank"profile" etc

But,I would like to know if a larger exhaust would improve the power on a turbo diesel ?

As I understood the internal combustion engine,a larger exhaust would normally lead to lower tourque(especialy at lower rpm) and a 'possibility' of higher power at much higher rpm

I have had the oppertunity to increase the power(by changing bore,stroke,cam profiles, headers,combustion chamber profiles etc) on a couple of petrol engine but are unfamiiliar with diesels !

[4ePikanini]

profile

• cam - lift and duration

- more lift = more air ( needs extra fuel ) = more power = if it exceeds a certain threshold it will rob torque and add power at higher rpm's = lumpier idle
- longer duration = can allow more air to enter and more exhaust gasses to escape allowing the engine to breath better can it certain instances also rob torque.

• crank - radius of the connecting rod journals can be different ( eg. swapping crank and pistons can change a vw 1.8 to a 2.0 without any changes to the block )

- bigger radius = shorter conrod-piston assembly = longer stroke = more displacement
- smaller radius = longer conrod-piston assembly = shorter stroke = less displacement

These profile descriptions are the general consensus but it is a very precise and complicated art to get the balance just right for a specific engine and it's requirements.




a larger exhaust usually adds power higher up and loses torque lower down

a larger and colder intake will assist everywhere, especially on diesels as they are
always WOT ( wide open throttle ) - power and rpm are determined by how much fuel ( diesel ) is added.

Diesel - more fuel = more power = more heat
petrol - more fuel = less power = less heat