merlinpjl
Active Member
I had a 2.5 diesel (BMW) P38 a few years ago, I had a box fitted by a company called Tunit. I also fitted a bigger intercooler and the power certainly went up. Not long after I had to have the gearbox and the transfer box completely re-built.
The boxes may well have be worn before I did the upgrade, but the increase in power probably shortened the amount of life left in them.
When towing my twin axle caravan with it, there was more power, but I did get overheating problems on hot days and long inclines - I suppose the extra power generated extra heat that the system just couldn't get rid of quickly enough!
Changed for a 4.6 eventually.
The boxes may well have be worn before I did the upgrade, but the increase in power probably shortened the amount of life left in them.
When towing my twin axle caravan with it, there was more power, but I did get overheating problems on hot days and long inclines - I suppose the extra power generated extra heat that the system just couldn't get rid of quickly enough!
Changed for a 4.6 eventually.
Datatek
Well-Known Member
They don't overheat if the cooling system is good.
Littelwill
Well-Known Member
Once changed for a 4.6 box did you have anymore problems whilst you owned it
W
W
Littelwill
Well-Known Member
Jaackk I bet your right after re-reading that.
Littelwill
Well-Known Member
Any further experiences with remapping and power boxes?
Keep them coming....
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Keep them coming....
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lenb
Active Member
I've owned my current P38 for over 5 years and covered over 50,000 miles in that time with it chipped. I tow a large caravan and have done so for years. Started using a 'plug in" box but had a remap by a company called Ecopower Remaps. The max torque for this remap is only 4 ft/lb greater than the torque of a 4.0 so I am not worried unduly about the gearbox. A recent oil and filter change did not show anything untowards. I do drive (mostly) sensibly and find it easier to maintain 50-60 mph towing. New caravan has mtplm 1670 kg so 'fingers crossed' I don't regret this post 
Current mileage 137,000 miles.
Current mileage 137,000 miles.
i feel i need to slag off this thread...but i wont though i should...cos people arnt listening to comments..
zf22 sits behind 4 and 3.9 with no trouble..AND many many bmw's etc..a weedy little 2.5 will give it no trouble if cooling and oil system is in good nick..though i bet, no one here maintains their gearbox..
just like eas..its crap people say..yet when was it last serviced??..am i making my point??
diesels//more power=more diesel used..simples..so worse mpg..i fix them for a living..
now you want cleaner more efficient running..then install propane injection..lower charge temp and THEN advance timing..
opps did i av a go...? sorry..
zf22 sits behind 4 and 3.9 with no trouble..AND many many bmw's etc..a weedy little 2.5 will give it no trouble if cooling and oil system is in good nick..though i bet, no one here maintains their gearbox..
just like eas..its crap people say..yet when was it last serviced??..am i making my point??
diesels//more power=more diesel used..simples..so worse mpg..i fix them for a living..
now you want cleaner more efficient running..then install propane injection..lower charge temp and THEN advance timing..
opps did i av a go...? sorry..
Datatek
Well-Known Member
You are certainly right about gearbox servicing, but a diesel re-map gives 380Nm of torque at a little over 2K rpm, way over what the box is designed to take. As standard it relies on a torque reduction strategy to survive, a power box or re-map negates this.
The torque curve on the petrol is very different.
lenb
Active Member
The remap I have quotes max torque at 325nm so this is why I'm less worried. I have driven a friends 2.5 with a tune by a well known Coventry based company and it went like stink even with light throttle, now that I would expect to cause gearbox issues.
Littelwill
Well-Known Member
Thanks for that lenb. Was good to hear your experience with a remap.
And I think by now everyone reading this thread has about understood that you don't get more power for less fuel.
Keep them coming has anyone had a bad experience that has defiantly been caused by a remap? If so how long after? What's your driving style etc
W
And I think by now everyone reading this thread has about understood that you don't get more power for less fuel.
Keep them coming has anyone had a bad experience that has defiantly been caused by a remap? If so how long after? What's your driving style etc
W
Littelwill
Well-Known Member
Ok so just to restart this one again, We've determind that the extra torque of a remap can/will damage the auto gear box in a diesel p38. But will the added power/torque given by a PSI box not just do the exact same thing or does a PSI box not increase the torque to the same levels?
(i was asked this over the weekend and didnt have the answer so im putting it to you guys and ideas)
(i was asked this over the weekend and didnt have the answer so im putting it to you guys and ideas)
I think all that has already been explained.
Jovial John
Member
Had My 1997/8 DSE remapped in Blackpool in 2005, travelled from Watford, did 30mpg going up, thrashing the Motorway, hours later returned same speeds except while blind in torrential rain for quite a few miles, did 30/31.
Before remapping, a boring drive, after, very lively and enjoyable, now my preferred carriage, have compared it to 4.0l v8, seems better (discounting noise), haven't compared to 4.6 v8.
Currently only do 2x 2.5 mile trips in heavy traffic a day with one 20 mile each way trip once a week, averages 20mpg reaching 30mpg on motorway + A&B road mixture of 100 or so miles, car now done 155000 miles with no issues since remap (I'm gonna regret saying that, aren't I ?). No gearbox oil or filter change in the ten years I've had it and engine oil & filter change once a year, must look after it better, but there isn't a day I don't use it.
Before remapping, a boring drive, after, very lively and enjoyable, now my preferred carriage, have compared it to 4.0l v8, seems better (discounting noise), haven't compared to 4.6 v8.
Currently only do 2x 2.5 mile trips in heavy traffic a day with one 20 mile each way trip once a week, averages 20mpg reaching 30mpg on motorway + A&B road mixture of 100 or so miles, car now done 155000 miles with no issues since remap (I'm gonna regret saying that, aren't I ?). No gearbox oil or filter change in the ten years I've had it and engine oil & filter change once a year, must look after it better, but there isn't a day I don't use it.
