Defender 90 TD5 - Remapped. Power issues beyond 65mph

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Well sierrafery you are right that you never claimed that heat dives a turbo but someone else on this thread (namely ozzydeano) did repeatedly and to be honest I couldn't be bothered replying to the pair of you independently. I asked you to produce a proper experiment to prove your claims and you did, I didn't criticise you for it, all I said was that if it does actually do what they say it does I didn't think it would be much use for the two identical Cummins engines I run or my Landrover because the supposed results blanketing gives are of no benefit to me because I could remap and get loads more power without faffing about with a blanket and also because getting on boost a few points of a second quicker makes no difference to me. I just want these engines to produce raw torque and hold on when required and of course be as reliable as possible. Now if I desired to take my focus RS to stage 4+ Which is 500+bhp, forged the block and Pistons, ultimate remap, bigger turbo, bigger injectors, bigger intercooler, decat straight through exhaust, upgraded intake and exhaust manifolds, and I wanted to extract every last HP to do drag races then I may consider a blanket and lagging, but that would be about the last thing I did because from what you have shown me while there appears to be a benefit in some situations it is relatively minor in the grand scheme of things, For an old td5 diesel I, like many of the other contributors here, just don't see the point.

All of us here know we can get a td5 to produce enough power to blow itself up fairly easily through remapping, bigger turbo and doing work on the intake/exhaust. A td5 is not like a time attack mitsi running 750hp or a top fuel dragster where every single HP counts. I have had the pleasure of poking about under the bonnet of a 750hp mitsi and I can tell you there was no turbo blanket or any manifold/ exhaust lagging in sight. Just a forged block and Pistons, massive intercooler and turbo, massive injectors, top notch exhaust, top notch manifolds, modified ram intake and a top notch remap. There is a limit on what a td5 can do and it is very easy to take it to its limit without over complicating matters. You even admitted that you had changed the actautor of your turbo wastegate before you added the blanket so even you must admit to yourself that you have no real way of proving the new actuator wasn't the main factor that has helped your engine.

Anyway, for the person who kept trying to claim that it is heat that drives a turbo, who seems to use tractor pulling forums as their source, as the saying goes, when all else fails it's time to go to Wikipedia.
https://en.m.wikipedia.org/wiki/Turbocharger

Pay particular attention to the bit that talks about what form of energy drives a turbo, it ain't heat, it's kinetic. It ain't the most accurate source but it is about the easiest to understand and it clearly says that turbos are driven by kinetic energy. Anyone who claims otherwise has no understanding of basic physics and doesn't even understand how an internal combustion engine works let alone a turbo. Someone else came on here and claimed that heat drives a turbo because the exhaust gas temp drops once it leaves the turbo, that is of course correct, the temps do drop. The temp drops because the turbo extracts work ( harvests the kinetic energy) from the exploding exhaust gases which is incidentally something I had already said when trying to explain it was kinetic energy and not heat that spins a turbo. But anyway I'm out of here, what could have been a simple conversation has turned into a mess because some people haven't a scoob about basic physics, but hey that's the Internet for you.
 
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I think some of you need to go away and read about thermodynamics, and the 1st law of thermodynamics because sierra and Deano are correct

Heat is very important in a turbocharger.

High temp gas comes out of the cylinders, the turbo creates backpressure (as it is an obstruction to that gas wanting to just escape - it slows it down) on the engine causing exhaust pressure to be higher than atmospheric pressure.

A pressure and temperature drop (expansion) occurs across the turbo which is what drives the turbo. (Temp drops when you expand a gas). The hotter the gas the greater the energy potential for work.

We all know what happens on the cold side of the turbo - air is compressed which heats it up hence why we need intercoolers.

Contrary to popular belief the Pistons don't 'push' the exhaust has put the valves, the gas leaves the cylinders because it is expanding

So heat isn't solely what actually makes a turbo spin but it is a hugely important factor.
pistons do push the gasses out a well s the pull factor from previous gasses leaving and residual expansion from the power stroke ,obviously the hotter the gasses the the more pressure they can create, its the flow that drives a turbo in the end
 
You clearly said that heat had nothing to do with turbo function, see your reply below.

The flow of the exhaust is caused by the heat of it and it rapidly expanding, it isn't 'pumped' out the engine.

I think it's time we all bow out of this thread rather than go around in circles.
what do you think the pistons do as they rise on the exhaust stroke
 
As already mentioned, an engine is just a fancy air pump at the end of the day. The main driving force of even a bloody bicycle pump is you pushing the air out of the cylinder and into the tyre... not because your superheating the air lol.

Saying heat alone drives the turbo and is the main factor of creating boost is as bad as somebody I know thinking it was the flow of oil through them that spun them :D

An engine is the same but it also gets a big helping hand from thermodynamics as there's such good temperature and pressure increases and drops due to what's happening in the combustion cycle.

I think a turbo blanket on a TD5 is doing a much better job of keeping down the intake and engine bay temps however than what it'll be maintaining in exhaust gas energy however. It really is a case of every little helps so if you want to get the last little bit of power out of something, go for it :)

Sorry, I miss typed top earlier about my AAP I was getting on mine from being half asleep from Christmas dinner food coma :D
Should have written it's a 1000mbar of course! not actual pascals!!!

Would want to be driving around the top of the himalayas at least for a 1000Pa lol
 
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Just doing abit of reading as can't sleep from falling asleep on the sofa early last night from aforementioned food coma :D

I noticed on when checking for faults, I seem to be getting Driver Demand high the odd time. I must check again does this happen after it goes into limp mode but wondering if the throttle pot or loom from throttle to ecu had any issues, would it be linked to engine not reving freely under full load and also connected to the issue that seems common by the throttle being unresponsive for the first few seconds on start up.

It seems unlikely but also the week before last, I went through a large puddle and Defender wss unresponsive for a few seconds later which would signify the throttle loom or pedal itself got wet from water behind splashed underneath. it was by no means a flood and still miles away from submersing anything other than the walls of the tyres but just a thought :)
Went through other puddles since though with no repeat issues however.
 
Well sierrafery you are right that you never claimed that heat dives a turbo but someone else on this thread (namely ozzydeano) did repeatedly and to be honest I couldn't be bothered replying to the pair of you independently. I asked you to produce a proper experiment to prove your claims and you did, I didn't criticise you for it, all I said was that if it does actually do what they say it does I didn't think it would be much use for the two identical Cummins engines I run or my Landrover because the supposed results blanketing gives are of no benefit to me because I could remap and get loads more power without faffing about with a blanket and also because getting on boost a few points of a second quicker makes no difference to me. I just want these engines to produce raw torque and hold on when required and of course be as reliable as possible. Now if I desired to take my focus RS to stage 4+ Which is 500+bhp, forged the block and Pistons, ultimate remap, bigger turbo, bigger injectors, bigger intercooler, decat straight through exhaust, upgraded intake and exhaust manifolds, and I wanted to extract every last HP to do drag races then I may consider a blanket and lagging, but that would be about the last thing I did because from what you have shown me while there appears to be a benefit in some situations it is relatively minor in the grand scheme of things, For an old td5 diesel I, like many of the other contributors here, just don't see the point.

All of us here know we can get a td5 to produce enough power to blow itself up fairly easily through remapping, bigger turbo and doing work on the intake/exhaust. A td5 is not like a time attack mitsi running 750hp or a top fuel dragster where every single HP counts. I have had the pleasure of poking about under the bonnet of a 750hp mitsi and I can tell you there was no turbo blanket or any manifold/ exhaust lagging in sight. Just a forged block and Pistons, massive intercooler and turbo, massive injectors, top notch exhaust, top notch manifolds, modified ram intake and a top notch remap. There is a limit on what a td5 can do and it is very easy to take it to its limit without over complicating matters. You even admitted that you had changed the actautor of your turbo wastegate before you added the blanket so even you must admit to yourself that you have no real way of proving the new actuator wasn't the main factor that has helped your engine.

Anyway, for the person who kept trying to claim that it is heat that drives a turbo, who seems to use tractor pulling forums as their source, as the saying goes, when all else fails it's time to go to Wikipedia.
https://en.m.wikipedia.org/wiki/Turbocharger

Pay particular attention to the bit that talks about what form of energy drives a turbo, it ain't heat, it's kinetic. It ain't the most accurate source but it is about the easiest to understand and it clearly says that turbos are driven by kinetic energy. Anyone who claims otherwise has no understanding of basic physics and doesn't even understand how an internal combustion engine works let alone a turbo. Someone else came on here and claimed that heat drives a turbo because the exhaust gas temp drops once it leaves the turbo, that is of course correct, the temps do drop. The temp drops because the turbo extracts work ( harvests the kinetic energy) from the exploding exhaust gases which is incidentally something I had already said when trying to explain it was kinetic energy and not heat that spins a turbo. But anyway I'm out of here, what could have been a simple conversation has turned into a mess because some people haven't a scoob about basic physics, but hey that's the Internet for you.

yes it was me who said heat drives a turbo other wise to make full boost pressure the TD5 will need to be sitting close to redline just to make full boost

but this isn't the case I have just come back driving mine ..engine up to operationg temps I was in TC lock up but I was still managing 15 to 17 psi boost pressure rpm NEVER ROSE ABOVE 2000rpm

reason for this the engine was seeing more load means more fuel more fuel = heat

other examples like blocked fuel filter ..this will still allow an engine rev but it wont be able to supply the fuel on demand ..resulting in low boost pressure

a common cause I see allot at work an engine suffers to make boost ..part of my diagnosing is to check fuel delivery..
if the fuel delivery checks out ....then air flow ie air filter clogged if this checks out ok we then inspect turbines and waste gates for correct specs and operation ..if this checks out we then test for boost leaks and change out sensors ..9 times out of ten its a chocked up fuel pick up enough to make an engine redline .as well as a blocked up add blue muffler .but not enough fuel to make boost on demand
ask your self this question
when the TD5 over boosts what does it do...does it cut out cylinders .....or does it fuel cut
if u ever experienced this when the Td5 fuel cuts ..but we still manage to make RPM ..wouldn't you think having this rpm we would have boost (you wont know no gauge installed )
no because there is less fuel to burn less fuel to burn means no HEAT ..a big reason you seen your mates HP car with bigger injectors

as for any turbo engine they seem a bit more responsive when up to operating temps ?
not to sure if any you notice that

you might not see turbo socks or wrap on a high power or show vehicle
because they already have the ceramic coated ..looks more professional and does the same job

as for the tractor pulling comment
i have worked with roadtrains for well over 20 years

another test i use if the laptop is not working
get into high gear cruising .now slowly push the brakes with the left foot at the same time we need to maintain speed
by pushing harder on the acc peddle ..boost rises
RPM does not

the same goes for the TD5 more load more fuel and isn't exactly RPM related

but most people on this thread don't have a boost gauge installed there only guessing
example this vid that you have bypassed many did because they hate to see the new things(or admit to being wrong )


how did i make more boost i was stationary and never went over 2000 rpm ohh i made more heat not flow


more heat to the turbo HOT SIDE runs more efficient its a known fact this is why they some install blankets and ceramic exhausts systems
then again why bother
why not just remap ..what does a remap do to achieve more power ?it certainly does not cool the charged air if that's what your thinking LOL
 
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Just doing abit of reading as can't sleep from falling asleep on the sofa early last night from aforementioned food coma :D

I noticed on when checking for faults, I seem to be getting Driver Demand high the odd time. I must check again does this happen after it goes into limp mode but wondering if the throttle pot or loom from throttle to ecu had any issues, would it be linked to engine not reving freely under full load and also connected to the issue that seems common by the throttle being unresponsive for the first few seconds on start up.

It seems unlikely but also the week before last, I went through a large puddle and Defender wss unresponsive for a few seconds later which would signify the throttle loom or pedal itself got wet from water behind splashed underneath. it was by no means a flood and still miles away from submersing anything other than the walls of the tyres but just a thought :)
Went through other puddles since though with no repeat issues however.
I've seen cases when low fuel pressure triggered driver demand fault code so IMO first of all rule out the fuel pressure cos the 3000rpm max revs is another sign of it, it's not uncommon for the pumps to loose the HP stage
 
farmerbrown your words

A td5 is not like a time attack mitsi running 750hp or a top fuel dragster where every single HP counts. I have had the pleasure of poking about under the bonnet of a 750hp mitsi and I can tell you there was no turbo blanket or any manifold/ exhaust lagging in sight. Just a forged block and Pistons, massive intercooler and turbo, massive injectors, top notch exhaust, top notch manifolds, modified ram intake and a top notch remap..

[/QUOTE]
how did you know the pistons are forged did you see them or was it just a read up on a flier you got handed to
was this a show vehicle why would they show there secret gains things are uninstalled like a dy ice box systems installed in the air intake are removed

please elaborate on the top notch exhaust system and there remap

then again whats the point of trying any Hp gains its an old landy ...so whats the point of a remap ..what would be the point of a larger intercooler ..all these mods help correct ,,just like containing the heat of a turbo engine all these aftermarket mods help
 
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farmerbrown your words

A td5 is not like a time attack mitsi running 750hp or a top fuel dragster where every single HP counts. I have had the pleasure of poking about under the bonnet of a 750hp mitsi and I can tell you there was no turbo blanket or any manifold/ exhaust lagging in sight. Just a forged block and Pistons, massive intercooler and turbo, massive injectors, top notch exhaust, top notch manifolds, modified ram intake and a top notch remap..
how did you know the pistons are forged did you see them or was it just a read up on a flier you got handed to
was this a show vehicle why would they show there secret gains things are uninstalled like a dy ice box systems installed in the air intake are removed

please elaborate on the top notch exhaust system and there remap

then again whats the point of trying any Hp gains its an old landy ...so whats the point of a remap ..what would be the point of a larger intercooler ..all these mods help correct ,,just like containing the heat of a turbo engine all these aftermarket mods help[/QUOTE]


How did I know? Because the owner told me and talked through what he had done to the car. 750hp for a mitsi is not crazy power nor is there any great secret to doing it just plenty time and money, I've seen time attack mitsi's running 950hp.

Top notch exhaust? B expensive custom built stainless straight through system with equal length headers etc. Top remap? There are remaps and remaps, a top notch one in my eyes is putting the car on a rolling road and tuning it the whole way through the Rev range.

I see you are still putting the cart before the horse.
 
how did you know the pistons are forged did you see them or was it just a read up on a flier you got handed to
was this a show vehicle why would they show there secret gains things are uninstalled like a dy ice box systems installed in the air intake are removed

please elaborate on the top notch exhaust system and there remap

then again whats the point of trying any Hp gains its an old landy ...so whats the point of a remap ..what would be the point of a larger intercooler ..all these mods help correct ,,just like containing the heat of a turbo engine all these aftermarket mods help


.[/QUOTE]

just all talk or should I say hear say
I also have friends who run hi power cars mainly supras with the 2jz engine some of the **** comes from there mouths is unreal ..specially when you talk to them a week or to later they have forgotten what the lied about or who they told in the past specially when it comes to tunning ..they tell you it makes all sorts of power through the rev range its been dyno tested 4 times but like I say a few weeks later ..they tell you its been dyno tested once it needs to go back in to be retuned (human nature )

as for other small tests farmerbrown have you actually done

have you tested wrapping have you tested larger intercoolers ..have you tested remaps bigger exhausts etc but then again what the point its an old landy

if not start from the beginning and install a boost gauge this will be at least a good start!!! get to know how a turbo works though different engine loads

then again its an old landy ,,so this means a remap wont work right ? ohh I forgot its an old landy the only mods where allowed to do is larger intercooler and a remap ..other mods will not see any benefits ..is this correct? ... every mod helps mate regardless if its an old landy

could be as simple to wrapping to contain heat goes alongway
other mods like EGR delete also goes along way ..how does an engine reburn an inert gas?
 
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God, at least learn to quote properly, its almost impossible to follow your responses, or who is saying what

I do apologise on that behalf ..not to sure why my PC does that it seems to duplicate... so I now using the laptop
but please GOD when will you guys understand how a turbo generates its energy

otherwise shut ya hole
 
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I've seen cases when low fuel pressure triggered driver demand fault code so IMO first of all rule out the fuel pressure cos the 3000rpm max revs is another sign of it, it's not uncommon for the pumps to loose the HP stage

Thinking this could well be the case. Got the injectors tested before I fitted them when putting the engine together and they are serviceable and will work fine but the tester said they could be slightly better for flow if he was being really particular. It runs perfect but as I said, I'm waiting to get a new set of injectors into it and also wire up a fuel pressure gauge soon in a week or so :)

When sure of the fuel system then, I'll take another look at things and dig a little further if still seem to have the issue. Very odd though in that it seems to be getting better and better with some miles. It's actually quite abit of effort and really need to intentionally make it go into limp mode now and seems far more eager to rev beyond 3000rpm too as before even if not really pushing it, it still wouldn't be that willing to go about 2500-3000.



Ozzy, insisting on a turbo just mainly works on heat now is getting old. Even your excuse of low engine load still producing boost is flawed too especially these days when we have such clever systems of engine management.
At no load and at full throttle, the engine sees that the driver demand is asking for much more rpm and power than what it's currently doing so it dumps a load of fuel in, this creates a bigger bang, more exhaust gases as well heat is released into the turbo, the turbo is allowed make some boost, more air gets taken in, bigger bang again, more exhaust, more heat until the engines rpm is matched to what is being asked from it.
On my TD5, I can make over a bar of boost while stationary as I have a fairly heavily tuned fresh engine and a variable geometry turbo and upto 1.5 bar even before 2000pm when a standard TD5 would be doing well to make a little bar.
Heat has alot to do with it as my viscous fan seems to be having trouble to even keep up at low rpm at heavy load for example while towing in 5th at low speeds but alot has to do with the fueling and the engines mechanical spec too.

If it was just heat that creates all the power, I could have saved myself a ball of money lol
 
dave M sport
no fuel no bang = no heat
its a known fact ! if the engine management was that good why would we change it ?
as for your viscous struggling .... ITS DOING ITS JOB
do you have A EGT gauge installed ?
if your tuned TD5 is that good why is the fan locking in to soon compared to a stock ecu
ask your self that question ?
the viscous is not struggling its doing what it designed to do it locks up when it detects to high of a temp
 
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I know the viscous is doing it's job! Can bloody hear it!!! It's just that it doesn't seem to be quite enough unless engine is reved abit more to really get it drawing a decent amount of air. Half the problem was a friend temporarily put my reg plate on the grille while helping me do a few jobs for the mot and forgot about it until I went towing the other night. cut that off again and it's better since but still a little paranoid so getting a new alloy rad and heater matrix lol.
Must check the tensioner too, even though it's new it might not being putting enough tension and slipping a little bit which would cause a whole host of problems with slower waterpump and fan speeds. Should notice the steering to be heavy if that was the case however

Don't have an EGT yet as waiting until the new year for madman to be back to send me my EGT and EMSII and other gauges and things from Merlin and Croytec so will know alot better once I know the full story of whats going on. As useful as it is, the nancom can only tell half the storry :)

ECU is a remote map from Alive so I'd be fairly confident, it's a safe tune. My rebuilt engine having slighly more compression and things would have it's part in generating more power and more heat too of course :) Bloody thing is nearly as fast as one of my race cars to 60 (even if one in question is the slowest of them as a little Fiesta zetec :D)
 
when the viscous is locked its also robbing power
my viscous fan only locks in when I need it most ..I run a normal ecu as I know of
40 degree heat here in Australia ...with air con on viscous might lock in a few times depending on driving conditions
Ireland has colder conditions so ask your self why is the fan locking up

how many Td5s will pull away from V8 SS utes (not many ) compared to small 4 banger feistas
I know mine does
I installed some thing better than a remap

as for belt tensioner there are a few sizes mine is 8 pk 1800 .i changed this out because the 1840 or the 1870 made my belts squeal when under load (cant remember exact numbers )
i only mention this because i also nearly purchased a new belt tensioner running these larger belts still never made me over heat though
 
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Yep, viscous snaps plenty! if idling can really hear the moment it locks up and puts the load on the engine for a moment.

Haha, my Fiesta is only 800kg and is able to keep up with Type R civic's when on track lol. My E30 318is is maybe around 115mph or so terminal speed out of a toll-ahem, private drag strip nearby and that's as fast as a standard E36 M3. My own E46 M3 probably do about 140 or more but haven't bothered trying yet lol

The Fiesta is about 80mph or so and the 110 wasn't that far off even when not pushing it that hard as was trying to stay off full boost and changing gear below 3k which I thought was pretty impressive for a 2 tonne brick to be fair :)


That's interesting about the tensioner belts!!! I didn't know there were different versions so will look into that as I only thought it was two sizes in such as Air-con and non air-con and there's a big difference between them:) Having the fan come in so much is indeed odd for such a over-speced system from the factory and even though fairly well modded, it still isn't anywhere near as far as they can be taken in even bigger turbos or even in stroker kits
 
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