Diesel P38 - Which Chip to go for?

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Datatek said:
I don't think even tight fisted LR would compromise an engines performance by fitting an air filter with insufficient air flow. Put the car on a rolling road and do a before and after HP check, I doubt you would find £24 worth of difference.
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I have a K&N on mine. To be fair it did give a couple of MPG improvement when first fitted. Over what was a fairly new standard filter. BUT, K&Ns need to be washed, cleaned and re-oiled, the kit for this costs about £10.00. Any oiled filter will gather dust to clog it a lot faster than a dry filter. Because the dust sticks to the oil, that is why it's used. So the K&N may go off sooner. £10.00 for a re-oiling kit and the washing and oiling time against £4.00 for a new standard filter that just drops in is a no brainer. So all in all i would say stick with standard and change it twice as often. It will still be cheaper than running with a K&N.
 
Datatek said:
I don't think even tight fisted LR would compromise an engines performance by fitting an air filter with insufficient air flow. Put the car on a rolling road and do a before and after HP check, I doubt you would find £24 worth of difference.
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I fitted one to my van and yeh i did think it made a differance... or was it just in my head coz you can hear the turbo whistle louder??? makes you think doesnt it.;)
 
Mike v.t.s said:
I fitted one to my van and yeh i did think it made a differance... or was it just in my head coz you can hear the turbo whistle louder??? makes you think doesnt it.;)
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The only possible advantage a K&N free flow filter can give would be off turbo. In other words at speed below were the turbo is working, below say 2,000 rpm. Above that the turbo sucks air in and the manifold is constantly pressurised. At higher RPMs a tea cloth stretched across the filter box would be as good as anything. They may have certain minute (and they are minute) HP advantages for a normally asperated engine at all engine speeds, were the engine itself is sucking air, but not for a turbo.
 
wammers said:
The only possible advantage a K&N free flow filter can give would be off turbo. In other words at speed below were the turbo is working, below say 2,000 rpm. Above that the turbo sucks air in and the manifold is constantly pressurised. At higher RPMs a tea cloth stretched across the filter box would be as good as anything. They may have certain minute (and they are minute) HP advantages for a normally asperated engine at all engine speeds, were the engine itself is sucking air, but not for a turbo.
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I know its a bit different and the airflow is not forced, but on a bike when changing from a conventional filter to a K&N you definitely have to re-jet to get more fuel into the cylinder in order to maintain the correct mixture. I would of thought that any form of restriction is not desirable under any circumstances.

Having said that, in the biking fraternity it is the general feeling that the higher flow filters, even when oiled, do not filter as well as the standard filters.
 
BladeRob said:
I know its a bit different and the airflow is not forced, but on a bike when changing from a conventional filter to a K&N you definitely have to re-jet to get more fuel into the cylinder in order to maintain the correct mixture. I would of thought that any form of restriction is not desirable under any circumstances.

Having said that, in the biking fraternity it is the general feeling that the higher flow filters, even when oiled, do not filter as well as the standard filters.
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Always ran without filters on the race bikes/cars:D
 
BladeRob said:
I know its a bit different and the airflow is not forced, but on a bike when changing from a conventional filter to a K&N you definitely have to re-jet to get more fuel into the cylinder in order to maintain the correct mixture. I would of thought that any form of restriction is not desirable under any circumstances.

Having said that, in the biking fraternity it is the general feeling that the higher flow filters, even when oiled, do not filter as well as the standard filters.
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Think i said that. I think normally asperated engines were mentioned. You will get slightly improved air flow. If the K&N was not oiled it would be useless as a filter, as i also said a tea towel stretched over the filter box would do the same job. Until the Jap stuff started coming over here you never saw an air filter on a motor cycle.
 
wammers said:
Think i said that. I think normally asperated engines were mentioned. You will get slightly improved air flow. If the K&N was not oiled it would be useless as a filter, as i also said a tea towel stretched over the filter box would do the same job. Until the Jap stuff started coming over here you never saw an air filter on a motor cycle.
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Does an old and dirty air filter make no difference to performance when the turbo is on?
 
Reference diesel chips. Last lot of chips i got in Blackpool tasted like they had been fried in diesel. Or is that not what we are on about. :D:D:D
 
Went for the Rimmer Bros one in the end and fitted it last weekend ... what a difference! Car is so much smoother to drive, overtaking is more fluid and she just seems to glide along! Already notices a +3mpg improvement on fuel consumption too to 19.5 and that's just on town driving with an average speed (according to the display) of 14mph!

But now the O Rings seem to have given up the ghost ... damp carpet on drivers side and warm/hot liquid dropping onto left foot whilst driving ... :(
 
kiwi4 said:
Hi, my DSE has a superchip fitted, will worth it, economy is 9-9.5 litre/100km and the peak torque curve is at about 2500rpm-3000rpm, so at a 100km/hr you are cruising at 2300rpm right in the torque range.

Hi 300AJC what was the upgraded air filter you got?
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Any chance of those figures in old money please? (Gallons & miles)

Thanks
 
mikedrinkwater said:
Any chance of those figures in old money please? (Gallons & miles)

Thanks
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The dash display (computer) is telling of an improvement in mpg due to improvements in input data from sensors, but no one has told the original computer theres another mini-computer in the system lying to the injectors on long to keep injecting fuel....:rolleyes:

Hence visual improvement to eyes, but not necessarily to the pocket....:doh:

Depends on how the vehicle is driven, now please, ignore the dash mpg and calulate the mpg figure using brim to brim mpg. figures....;)
 
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zzr1200 said:
The dash display (computer) is telling of an improvement in mpg due to improvements in input data from sensors, but no one has told the original computer theres another mini-computer in the system lying to the injectors on long to keep injecting fuel....:rolleyes:

Hence visual improvement to eyes, but not necessarily to the pocket....:doh:

Depends on how the vehicle is driven, now please, ignore the dash mpg and calulate the mpg figure using brim to brim mpg. figures....;)
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It does surprise me so many people don't get this!

I too would be very interested to see some brim-brim comparisons with a chip fitted if anybody does have this info, would be much appreciated.

I do think the 2.5D engine could happily put out a few more bhp (it did in my 325TDS - 150bhp IIRC), but I am not particularly interested if all the chip does is alter the throttle position:fuel injected map. The throttle response is for sure set up in a very 'lazy' way which does make the DT feel sluggish, and there is loads of throttle travel - I presume this is to allow finer control when off road?

So as well as real fuel consumption data (my expectation is that a chip should make little or no difference), does anybody have any dyno evidence to back up power improvement claims?

Cheers,

Jerry
 
jerrytlr said:
It does surprise me so many people don't get this!

I too would be very interested to see some brim-brim comparisons with a chip fitted if anybody does have this info, would be much appreciated.

I do think the 2.5D engine could happily put out a few more bhp (it did in my 325TDS - 150bhp IIRC), but I am not particularly interested if all the chip does is alter the throttle position:fuel injected map. The throttle response is for sure set up in a very 'lazy' way which does make the DT feel sluggish, and there is loads of throttle travel - I presume this is to allow finer control when off road?

So as well as real fuel consumption data (my expectation is that a chip should make little or no difference), does anybody have any dyno evidence to back up power improvement claims?

Cheers,

Jerry
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How can that be the only way to increase dramatically the bhp/torque in an otherwise unmodified diesel is to increase the fuel quantity injected. There is no other way of doing it. I wish all these idiots would stop coming on here and saying i had 150bhp and 350 lbs ft of torque doing 25 mpg. I fitted a XYZ chip and now have 190bhp, 450 lbs ft of torque and doing 30 mpg. IT'S NOT BLOODY POSSIBLE.
 
wammers said:
How can that be the only way to increase dramatically the bhp/torque in an otherwise unmodified diesel is to increase the fuel quantity injected. There is no other way of doing it. I wish all these idiots would stop coming on here and saying i had 150bhp and 350 lbs ft of torque doing 25 mpg. I fitted a XYZ chip and now have 190bhp, 450 lbs ft of torque and doing 30 mpg. IT'S NOT BLOODY POSSIBLE.
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Ya forgot increased/cooler air flow as it's fuel/air mixture that improves performance.

So bigger intercooler and increased fuel qty is the only way to improver performance. However if Fuel/air is electroinically controlled via an ECU then a chip may be able to alter the factory settings and supply more fuel/air.
 
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