[sriku]

Originally Posted by gd1418

Now in HVK's case, since the K&N is open and is also drawing hot air from the engine bay, he would face problems on altitudes as the hot air will any case be more thinner than the already thin cold air..

The "Transporter" is getting a performance bump in the plains where the air is denser and the engine is getting more and proper air than what the OEM filter used to provide. It will be different in altitudes.

Thanks for the information. What do you suggest then? go back to the OEM air filter and ditch the K&N? What if we replace the filter element in the OEM filter box with the K&N and seal it into place. In this case the cold air delivered from the OEM air feed would enter the airbox with the K&N element and we could possibly have the best of both worlds? Or am I trying to have my cake and eat it too.

Cheers,

[hvkumar]

Thanks, SriKu, for initiating this discussion. Now I am more and more confused, although I am convinced about the hot air argument, which is simple physics.

[nitrogary]

hot air has lesser density. you are much better with cooler air. cooler the air, better it is for the engine. always...

@ sriku
diesels run on excess air. and for your scorpio, there is a turbo. It will not matter much where you put a k&n filter. the drop across the filter will be hardly 10-15 mbar less as compared with the stock filter. If m&m filter has a drop of 50-70mbar, k&n will have a drop of say, 46-60 mbar.
now, turbo boost is about 1100-1200 mbar at peak torque and maybe until rated. so you figure out how much difference will 1100 mbar and 1110 mbar will make for engine performance. In terms of percentage, it is less than 1%
you are making 220-230 Nm torque normally with the oe filter and now you ll make 222-232...

do you feel its worth it?

for a gasoline engine which works on narrow band lambda ratio, you are welcome to put higher flow filters. But please substitute it with corrected fuelling.

diesels dont get affected much about the filters. they will gulp only as much as they need. ofcourse intake depression plays a part in this, but not so much.

if you need further clarification, please feel free to PM me. i work with M&M engine development and i have worked on the 2.6 litre for some time.

cheers!
nitro

[HIGHNOON]

The tata 475 IDI tc on my Turbo Indigo works best when the air is cooler or if its raining like. Gets sluggish every time its hot outside. So did my Fiat UNO & also petrol accent. My earlier NA Indica was simply terribly sluggish in hot sun but was quite ok in monsoon / colder weather even with the AC laways on.

[ritedhawan]

Cooler the air , oxygen density high, allows more fuel to be added to it and thus able to extract more torque. Quite understandable.
But youre not taking into account the cold start condition in colder climates, i think in colder climates , starting a diesel engine in cold start may became a problem especially a non-CRDi engine like :say a diesel engine with a inline -distributor pump and IDI. Cool air mixed with fuel enters the combustion chamber , at the end of power stroke, combustion does take place but incomplete. No wonder, that undulating noise from the engine, and exhauxt spewing out black soot, sign of unburnt carbon or unburnt fuel. Here your 'cool air always good' statement runs flat!. The essential thing here is heating the combustion chamber, glow plugs come to aid here. Try starting this engine with its glow plugs gone , would have to push the accelerator to full with all that unburnt fuel coming out of exhauxt in the form of black soot. Why are we doing this, just because we want to bring the combustion chambers to ideal temperature for combustion.

EGR is an ideal way of incresing the fuel effeciency. The unburnt fuel coming into the exhauxt is treated with an ad-blue mixture and then got into the intake stream with incoming fresh air going for the combustion. With-out EGR, this unburnt fuel will uselessly be thrown out into the open.Ins't it better to extract as much as possible from the fuel?

[HIGHNOON]

Originally Posted by ritedhawan

Cooler the air , oxygen density high, allows more fuel to be added to it and thus able to extract more torque. Quite understandable.
But youre not taking into account the cold start condition in colder climates, i think in colder climates , starting a diesel engine in cold start may became a problem especially a non-CRDi engine like :say a diesel engine with a inline -distributor pump and IDI. Cool air mixed with fuel enters the combustion chamber , at the end of power stroke, combustion does take place but incomplete. No wonder, that undulating noise from the engine, and exhauxt spewing out black soot, sign of unburnt carbon or unburnt fuel. Here your 'cool air always good' statement runs flat!. The essential thing here is heating the combustion chamber, glow plugs come to aid here. Try starting this engine with its glow plugs gone , would have to push the accelerator to full with all that unburnt fuel coming out of exhauxt in the form of black soot. Why are we doing this, just because we want to bring the combustion chambers to ideal temperature for combustion.

EGR is an ideal way of incresing the fuel effeciency. The unburnt fuel coming into the exhauxt is treated with an ad-blue mixture and then got into the intake stream with incoming fresh air going for the combustion. With-out EGR, this unburnt fuel will uselessly be thrown out into the open.Ins't it better to extract as much as possible from the fuel?

I guess we are assuming that your vehicles is in optmium condition to start with. No point in discussing the intake air temp if your glow plugs are busted. We are discussing the behavior / performance of a diesel engines specifically non crdi with warm air?