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These "older" engines are a bit of a favourite for a lot of people, including myself... ;)

Your question in my mind solely depends on your budget really.

If I was spending £1000+ on a new turbo then I'd probably look at fettling the engine too, but these engine are incredibly hardy, and if its running well now, then there's no reason why it shouldn't run ok with a new turbo, if you're putting a purpose built kit on like the ali sport ones. They recommend an upgraded intercooler so that will add to your upgrade costs too...

A VNT turbo mainly extends the power range, rather than vastly increasing it, so the stress on the engine shouldn't really be changing that much... but having said all that if its mega high millage, it might be time to give the whole engine an overhaul.... :)

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It only puts extra strain on the engine if you set it up to do so.

Surely a waste of time and money if you don't set it up to do so?

...and yes, I did call you shirley :ph34r:

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It only puts extra strain on the engine if you set it up to do so. There's probably better ways to spend £1k on an old TDi though.

Like what? If the engine is in fine fettle, intercooler is already upgraded, fuelling and boost moderately adjusted to suit the IC, this could be a reasonable upgrade. Although i have heard of a few folks getting hybrid turbos built for less from some turbo specialists (as oppose to Land rover diesel tuners).

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A VNT turbo mainly extends the power range, rather than vastly increasing it, so the stress on the engine shouldn't really be changing that much... but having said all that if its mega high millage, it might be time to give the whole engine an overhaul.... :)

HP = torque x rpm / 5252

To get more power, you need to make more torque at lower rpm, or the same or greater torque at higher rpm.

A VNC turbo can flow more air, so while the boost, a measure of resistance might not change so much, you'll have higher cfm of air at higher rpm, thus a 'bigger' bang, more torque and more hp. So certainly more strain.

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Does any one have experience of these on older engines?

I have a high mileage 200tdi, if I were to fit one should I have the engine rebuilt first to help with the extra strain?

I suppose a couple of questions. Are you running a completely stock Tdi now? If not, then you may just want to tune the injector pump and fit a bigger intercooler. Lots of choice on intercoolers if you don't mind a bit of fab work.

This represents very good value for money given the return in performance.

Next up, what do you actually want to achieve with the engine? Because above and beyond injector pump tuning and a bigger intercooler. Most other mods will be expensive and may not yield as noticeable results, certainly a far lower £/HP ratio.

So you have to consider, are there simply better options for more power?

Personally I love the Tdi's, but if you really want more than say 120-135hp (max 150hp), then you are better off using a different engine. An engine swap might sound like a bigger project and more costly. But once you add up all the bits you're likely to do on a Tdi, then I suspect the costs are a lot closer. And done correctly, an engine swap will massively exceed the Tdi.

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I agree with what's been said here,

I looked at getting a bit more out of my 200tdi but it wouldn't deliver the sort of gains I wanted for the cost. The v8 was the cheapest option for me when you look at the £/BHP ratio, it's not a daily so I'm not particularly bothered about fuel

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Thanks everyone

I suppose a couple of questions. Are you running a completely stock Tdi now? If not, then you may just want to tune the injector pump and fit a bigger intercooler. Lots of choice on intercoolers if you don't mind a bit of fab work.

This represents very good value for money given the return in performance.


Next up, what do you actually want to achieve with the engine? Because above and beyond injector pump tuning and a bigger intercooler. Most other mods will be expensive and may not yield as noticeable results, certainly a far lower £/HP ratio.

So you have to consider, are there simply better options for more power?


Personally I love the Tdi's, but if you really want more than say 120-135hp (max 150hp), then you are better off using a different engine. An engine swap might sound like a bigger project and more costly. But once you add up all the bits you're likely to do on a Tdi, then I suspect the costs are a lot closer. And done correctly, an engine swap will massively exceed the Tdi.

I'm running a stock 200tdi, which I like but would like to spread the power band and have a bit more oomph on hills. I'm not in for swapping to a different type of engine but not above having an engine overhaul.

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You can increase the lower rev turbo pressure by some apparent simple mods to the exhaust manifold that begins with the removal of the exhaust gate, closing it up and changing the internal profile to direct better/uninterrupted exhaust flow onto the turbo vanes meaning that the turbo spins faster at lower revolution speeds, this obviously involves installing a remote waste gate on the turbo discharge pipe - it can either blow off to atmosphere or back into the turbo inlet supply pipe.

A "local" company here in Sydney does this modification for about AUD$850.00 on an exchange basis for the manifold, they claim an increase of about 35% in the 750 - 2000 rev range for no loss of economy. This cost does not include the additional external waste gate however but these can be easily obtained on EBay of from after market stores.

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You can increase the lower rev turbo pressure by some apparent simple mods to the exhaust manifold that begins with the removal of the exhaust gate, closing it up and changing the internal profile to direct better/uninterrupted exhaust flow onto the turbo vanes meaning that the turbo spins faster at lower revolution speeds, this obviously involves installing a remote waste gate on the turbo discharge pipe - it can either blow off to atmosphere or back into the turbo inlet supply pipe.

A "local" company here in Sydney does this modification for about AUD$850.00 on an exchange basis for the manifold, they claim an increase of about 35% in the 750 - 2000 rev range for no loss of economy. This cost does not include the additional external waste gate however but these can be easily obtained on EBay of from after market stores.

Ah you're back! hope you had a successful trip! - you guys over the pond seem to be much more into engineered upgrades, I hope I get the chance to come over and seem some of it sometime! The Brit market is very much into the "bolt on" upgrade market, and you have to search or get into the right circles to find folk that upgrade stuff like that...

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Thanks everyone

I'm running a stock 200tdi, which I like but would like to spread the power band and have a bit more oomph on hills. I'm not in for swapping to a different type of engine but not above having an engine overhaul.

In that case, I highly recommend you get your injector pump tweaked. You can do it yourself (it's really easy, although I recommend fitting an EGT gauge first). It'll transform how the Tdi drives. It'll feel like you've given it 100hp extra, although of course you won't have. :)

If you don't want to do it yourself, there are still plenty of tuners about who will.

You don't need to go for a big intercooler and will see good gains without one, but a big intercooler will offer more gains.

As for engine swaps, they really aren't that bad. And there is lots of choice. Be it a straight swap to a V8. The Rover unit might not be the latest thing technically, but it's a very good power plant for 200-240hp. Power levels a Tdi could only dream of. Ok, mpg won't be as good, but it can be quite acceptable, especially given the power increase. And of course LPG options can make them lower £/mile on fuel than a diesel is.

But there are lots of options out there, including 3.0 M57 BMW diesel engine or a Chevy LS1 V8. They sound radical, but once you price up all the bits you might do to a Tdi, such as a rebuild or a 2.8 litre version, intercooler, tuning, exhaust, new turbo and maybe even a performance head and cam. And you can easily exceed or match the cost of fitting another engine. And still only have half the HP.

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You can increase the lower rev turbo pressure by some apparent simple mods to the exhaust manifold that begins with the removal of the exhaust gate, closing it up and changing the internal profile to direct better/uninterrupted exhaust flow onto the turbo vanes meaning that the turbo spins faster at lower revolution speeds, this obviously involves installing a remote waste gate on the turbo discharge pipe - it can either blow off to atmosphere or back into the turbo inlet supply pipe.

A "local" company here in Sydney does this modification for about AUD$850.00 on an exchange basis for the manifold, they claim an increase of about 35% in the 750 - 2000 rev range for no loss of economy. This cost does not include the additional external waste gate however but these can be easily obtained on EBay of from after market stores.

Do you have anymore info on this or a link? Only curious, because the eng of your post you sound like you are talking about a dump or blow off valve. Something a stock diesel doesn't have. And something different to a turbo wast gate.

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Do you have anymore info on this or a link? Only curious, because the eng of your post you sound like you are talking about a dump or blow off valve. Something a stock diesel doesn't have. And something different to a turbo wast gate.

I didn't read it as talking about a dump valve - it seems clear to me Iain is describing an external wastegate setup, something common on tuned turbo petrol engines

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Im currently rebuilding a Defender 200tdi engine from the block upwards. The engine and turbo is pretty shot so am looking at an extensive rebuild.

I've previously looked into and wanted to include a VGT into the rebuild but I'm sticking with a standard turbo. The reason being that the VGT produce torque/power at lower revs but I don't believe this is a good thing for the gearbox/crankshaft.

I'd rather be running higher revs/lower/smoother loading than lower revs/big heavy 4 cylinder thumps thru a gearbox that's close to its design limits already.

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Lewis, Chicken Drumstick and Maverik, okay the company making this modification are based in a Northern suburb of Sydney and they wouldn't allow me to take snaps of the modified exhaust manifold - especially as I couldn't afford to buy one and I was only "looking" but the shaft port of the standard waste gate had clearly been welded up and a new welch plug fitted revealing that the standard waste gate had been removed, according to them a special diverter plate is fitted internally into the void made by the removal of the waste gate to direct increased exhaust gas onto the turbo vanes generating additional turbo revs and turbo generated air pressure at lower engine speeds.

They also supply - as part of this modification - at an outrageous cost an external waste gate that is installed in the solid supply pipe between the turbo and intercooler and bleeds excess air back into a "T" which is installed into the feed pipe from the air filter to the turbo - this is installed before the turbo and after the oil breather line. I think a cheaper unit can be purchased from EBay of from any auto accessory dealer. As I recall in order to fit this "T" piece the oil breather line has to be relocated closer to he air filter and the hose extended, I think that they may have used new air hoses.

The claimed increase in power 750-2000 Rpm is about 35%.

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RNP, the strain on the engine/crankshaft and gearbox by increasing low end torque is negligible, if an engine such as the 200/300 Tdi are designed to run with a combustion pressure of between 12.5 (200tdi) and 14.7(300tdi) psi then it will withstand that combustion pressure regardless of the engine revolutions. Also the gearbox will withstand much more power that your 200 Tdi will produce, my 300tdi was, when I rebuilt it. balanced to 12000rpm, and the shocks on the gearbox come from the elderly loose nut behind the steering wheel, not from the engine.

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its not so much the amount of torque produced but the fact its producing that amount lower in the rev range - the four cylinder 'bangs' are further apart - whereas at higher revs and where a tdi normally comes on boost the combustion pulses are closer together which my tired brain reckons is better for a gearbox (?)

Its how I drive my Ford Transit even though it has a VGT and does pull from low down I dont want the expensive DMF taking a hammering.

Incidentally - whereabouts is the LR you mentioned above? - im paying my brother a surprise 40th birthday visit in a few weeks and the pound is strong against the Oz dollar at the moment.

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