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Idea 1.9 JTD Twin Turbo?

I was speaking to a friend who is an alfa tech and who previously worked at Saab. We were discussing the my 1.9 16v JTD and how it is also used in the Saab 9-3. He also mentioned that the 9-3 has a twin turbo version of the alfa engine. The second turbo is piggybacked on the first and it all sits nicely on the manafold. Car produces 177bhp and over 300ft/lb according to wiki as standard So my question is why has no one done this? A search on the forum reveals no threads on this option and yet there are many threads regarding turbo modifications from 2.4 etc where lots of fabrication needs to be done which I know is not possible for some to achieve. According to my tech mate he said even the ECU is the same so in theory it wouldn't take much to have a twin turbo 156/147. I even have a VNT solenoid off a 9-3 currently fitted to my 156 as mine was duff and he had one kicking around in the bottom of his tool box. It's the same part

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It's actually a biturbo setup with a smaller turbo feeding a larger one and with a bypass valve. Strangely enough the term "twinturbo" is chosen wrong by the factory.

Fiat only used this engine in the Lancia Delta, where it produces 190 Hp and 400 Nm.
Indeed the Saab also uses it, but it's a little bit downtuned.

It might look simple to install, but it's harder than you think. Think about all the plumbing, the boost control of 2 turbo's instead of one and the space you need to pack this.

On Fred's TDI Page. TDIClub.com. VW TDI Enthusiast Community somebody is working at a similair build (compound setup) you can see how much it involves. Twice the turbo = minimal twice the costs and twice the time involved.

And why bother if you can get close to biturbo performance with a GTB2056v turbo which is far easier to adapt ?

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I see what you are saying J but would it not just be a bolt on upgrade? As the parts exist for the engine. Surely this is easier than chopping and welding bits of turbo together. Not that I don't love the GTB thread and I think it's a mavelous bit of engineering skill but that seems far more involved than just canibalising a Saab 9-3 or indeed the Lancia no? If you were building something from scratch then yeah I agree leaving single turbo's would be much easier but as the engine actually exists in several forms. One even from the fiat stable then surely this would be a totally pheasable option.
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just double troubles. Doesn't worth on 1.9 JTD imho.
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I think the reason to bother, JS, is that 2 smaller turbos would be less laggy than 1 dirty great big turbo.

But I think engines with 2 turbos can be called "twin" or "bi" as both mean "2", there are 2 possible set ups though-parallel or sequential, think this is what you were getting at. AFAIK the JTD one is sequential.

When the twinturbo 1.9 was released, Fiat saved the 190 version for itself and limited non Fiat marques to the 180, now the 2.0 litre version is imminent, its allowed others the 190, so latest 9-3s have the option of it.

Tis very strange that Alfa never used it, though, but probably down to the fact that it would have made the 2.4 redundant as it would have been faster AND more economical than the 2.4. Now the 2.4 is dead, I m sure the 2.0 twin turbo will replace it in the Guilia and the Guilietta eventually.

The same Alfa tech bloke Joss mentioned reckons its a simple bolt on job, plus sorting the oil supply for the second turbo and hes worked on the twinturbos and single turbos a lot.

I think the reason no one has done it is the relative rarity of the twinturbo and the expense.

If you hadnt blown all that cash on a GTA, Joss, you could have spent some of it on a conversion !
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Quote:
Originally Posted by typos1 View Post
I think the reason to bother, JS, is that 2 smaller turbos would be less laggy than 1 dirty great big turbo.
Not necessarily true.
Actually the Lancia Delta TT has a small and a big turbo. A small one to make boost quickly and a big one to take over the flow in mid- and high rpm range. It is this particular setup that does give a benefit in working range.

Quote:
But I think engines with 2 turbos can be called "twin" or "bi" as both mean "2", there are 2 possible set ups though-parallel or sequential, think this is what you were getting at. AFAIK the JTD one is sequential.
Twin = two similair
bi = two different

So logically I'd call a V6/V8 or whatever with two similair turbo's (one for each cylinderbank) a twin turbo, and an engine with a small turbo and a big turbo a biturbo.
Indeed the 190 hp JTD engine is a sequential setup.

Quote:
When the twinturbo 1.9 was released, Fiat saved the 190 version for itself and limited non Fiat marques to the 180, now the 2.0 litre version is imminent, its allowed others the 190, so latest 9-3s have the option of it.

Tis very strange that Alfa never used it, though, but probably down to the fact that it would have made the 2.4 redundant as it would have been faster AND more economical than the 2.4. Now the 2.4 is dead, I m sure the 2.0 twin turbo will replace it in the Guilia and the Guilietta eventually.
Good point, I wonder if the sequential turbo setup really returns. The costs are high, and the evolution of the single diesel turbo is going fast. The Garrett GTB turbo does 30% more boost at 90% of backpressure compared to the GTA series.

Quote:
The same Alfa tech bloke Joss mentioned reckons its a simple bolt on job, plus sorting the oil supply for the second turbo and hes worked on the twinturbos and single turbos a lot.

I think the reason no one has done it is the relative rarity of the twinturbo and the expense.

If you hadnt blown all that cash on a GTA, Joss, you could have spent some of it on a conversion !
I doubt if it's a simple bolt one job. Who takes the challenge?
Here's one (or should I say two?):
Turbina per LANCIA, ALFA ROMEO 1.9 JTD DA 190 CV TWIN TURBO PER DELTA,e 159 | eBay
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It is not worth it... a decent GTB turbo beats "twinturbo" any day...
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Right, so twin is 2 parallel turbos and bi 2 sequentials.

All JTD 2 turbos (in Lancias, Saabs and Cadillacs) are bi-turbos, 160, 180 and 190 (in the 9-3 you can have any of those outputs).

Earlier I said that the 2.0 was "imminent" as I couldnt think of anything that uses it, but I ve remembered that the 9-5 does, so it is in production already . . . or should that be "was" as no Saabs have been made since April ! ?

Beemer's 2.0 bi turbo makes 218 PS and 332 lb/ft, the single makes 181/280 and I ve read a lot of reports that say theres very little lag. I remember when it was launched, reading a US car mag that said it was one of the best engines ever, high praise coming from a market were very few diesels are sold.

I think 2 turbos will always be better than one, especially if one is smaller.

I ll add that item to my watch list-it can join the various 156 Q4 parts I m watching ! He says its an Alfa unit and is used in the 159, though, I m pretty certain it never was.

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It is not worth it... a decent GTB turbo beats "twinturbo" any day...
Why dya say that Tribesman ?
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Since the 1.9JTD 16v twin turbo (or whatever you want to call it) was planned for Alfa Romeo but never happened, I would be similarly surprised if the set-up is ever applied to the 2.0 JTD.

In any case, the Fiat Group need to concentrate on applying MA to the JTDs. This would make them much more competitive at least in terms of power and CO2 outputs compared to say, BMW. At the moment, there is no comparison, the Germans hold all the trumps.
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IMHO biturbo setup makes sense on large displacement engines, where single big turbo spools rather slow and doesn't provide low rpms power. Latest GTB generation provides really decent power at low rpms already. Believe me ;-)

Mentioned Fiat group biturbo is BorgWarner one (R2S family probably)).


Btw it's not completely bolt on - you have to control valve (I.) splitting the exhaust gas flow somehow.

Last edited by yan.ko; 20-10-11 at 00:05.
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Quote:
Originally Posted by JS JTD View Post
I doubt if it's a simple bolt one job. Who takes the challenge?
Here's one (or should I say two?):
Turbina per LANCIA, ALFA ROMEO 1.9 JTD DA 190 CV TWIN TURBO PER DELTA,e 159 | eBay
Does that mean cars like the nissan skyline and toyota supra are really bi turbo and not twin turbo then as both of their set ups are sequencial and I believe they are different sizes too even though the call them twin turbos :think: . In any case I'd be up for the challenge if not to just be a little different. Plus having 2 turbos on the JTD would get everyone looking at it at meets Not sure what I'd do with your down pipe mate. I'd have to sell it on

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In any case, the Fiat Group need to concentrate on applying MA to the JTDs. This would make them much more competitive at least in terms of power and CO2 outputs compared to say, BMW. At the moment, there is no comparison, the Germans hold all the trumps.
I'm not interested in C02 I want POWER and drivability.

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IMHO biturbo setup makes sense on large displacement engines, where single big turbo spools rather slow and doesn't provide low rpms power. Latest GTB generation provides really decent power at low rpms already. Believe me ;-)

Mentioned Fiat group biturbo is BorgWarner one (R2S family probably)).


Btw it's not completely bolt on - you have to control valve (I.) splitting the exhaust gas flow somehow.
Surely all this can be taken from the Saab/Lancia part book. The contol valve and piping I've been told are piggy backed rather than two separate systems. Apparently the larger turbo is trying to spool at the same time the small one does it just takes longer which makes sense. Down pipes could be had from the other cars or manufactured.....fancy a challenge JS? which leaves the induction side of things which can be manufactured from standard prts right at the turbo inlet and silicone parts to match u to the JTD airbox. Basically boys I'm scared of welding!
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Quote:
Originally Posted by Joss
Does that mean cars like the nissan skyline and toyota supra are really bi turbo and not twin turbo then as both of their set ups are sequencial and I believe they are different sizes too even though the call them twin turbos :think:
The skyline and supra are actual twin turbo's with two small turbo's feeding 3 cylinders each.
With V-style or boxer engines is easier to use twins because of the plumping.

Quote:
Originally Posted by Joss
Surely all this can be taken from the Saab/Lancia part book. The contol valve and piping I've been told are piggy backed rather than two separate systems. Apparently the larger turbo is trying to spool at the same time the small one does it just takes longer which makes sense. Down pipes could be had from the other cars or manufactured.....fancy a challenge JS? which leaves the induction side of things which can be manufactured from standard prts right at the turbo inlet and silicone parts to match u to the JTD airbox. Basically boys I'm scared of welding!
Now that I look closer, it seems it's not entirely sequential. The comp outlet is parallel.
The extra valve probably bypasses the small turbo at a given airflow rate.
Also the large turbo is a simple wastegated one, and it looks the small turbo is free floating.
It looks like the exhaust ports @ the cylinderhead are different too.
For the downpipe, I can build one but then I need the original piece as a template.
Intake side shouldn't be that different to solve.

Quote:
Originally Posted by typos1
Beemer's 2.0 bi turbo makes 218 PS and 332 lb/ft, the single makes 181/280 and I ve read a lot of reports that say theres very little lag. I remember when it was launched, reading a US car mag that said it was one of the best engines ever, high praise coming from a market were very few diesels are sold.
With a biturbo it's possible to get a wider range than whatever single turbo, I agree.
But if I look at this Fiat unit from KKK there's no VNT involved to extend the working range.
So if you'd compare that to a single Garrett GTB unit I believe the difference is not that big.

I do believe it's useful to use a biturbo setup at whatever engine, because you can use a high pressure ratio/flow for high power combined with fast spooling.
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The skyline and supra are actual twin turbo's with two small turbo's feeding 3 cylinders each.
With V-style or boxer engines is easier to use twins because of the plumping.
Both are straight 6 though not v. As for the plumbing could we not use an original lancia downpipe as a template?
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I imagine that the old Maserati BiTurbo was a parallel set up
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the tuning boxes for the Lancia Delta TT JTD offer 230bhp & 335lbs, and that's with no other mods (DPF ect), so some good potential
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Nope, these turbos are hardwired and ECU has no clue it's controlling two turbos. If both valves (I. and II.) are really controlled by the same pressure regulator as Joss wrote, it would make any tuning even harder.

Btw. GTB2056V is still capable of little bit more power.

Btw2. Turbo is one of the most strained component on the turbocharged engine. I still don't know why would anybody mess up with freefloat + wastegated turbos instead of one quality VNT one on 1.9JTD.
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Nope, these turbos are hardwired and ECU has no clue it's controlling two turbos. If both valves (I. and II.) are really controlled by the same pressure regulator as Joss wrote, it would make any tuning even harder.

Btw. GTB2056V is still capable of little bit more power.

Btw2. Turbo is one of the most strained component on the turbocharged engine. I still don't know why would anybody mess up with freefloat + wastegated turbos instead of one quality VNT one on 1.9JTD.
It;s only what I've been told so can't confirm it's one regulator. One question though. Are they free float turbo's? The turbo on the 1.9 is held by a bracket at the bottom of the precat so would it not make sense that the twin will be as well? Although the small one on top seems to be free float or am I getting this mean mixed up. As for wastegated turbos why is there a problem with them? Many manufacturers use them?
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Both are straight 6 though not v.
My bad then!

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As for the plumbing could we not use an original lancia downpipe as a template?
Yes, that's what I meant.

Quote:
Originally Posted by Joss
One question though. Are they free float turbo's? The turbo on the 1.9 is held by a bracket at the bottom of the precat so would it not make sense that the twin will be as well?
Free float as in: no boost control (wastegate or VNT)
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My bad then!
Meh!

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Yes, that's what I meant.
Ah good. Well if I do it expect a large metal pipe in the post



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Free float as in: no boost control (wastegate or VNT)
Ah I see. My bad this time. So what am I refering too as I know you can get turbo that are supported by the engine and some that are supported by just the manafold?
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If you look into it, theres more than just parallel and sequential, different engine builders use lots of different 2 turbo set ups.
What theyre called is all just semantics, lets call em "2 turbo systems".

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Originally Posted by Spider95 View Post
Since the 1.9JTD 16v twin turbo (or whatever you want to call it) was planned for Alfa Romeo but never happened, I would be similarly surprised if the set-up is ever applied to the 2.0 JTD.

In any case, the Fiat Group need to concentrate on applying MA to the JTDs. This would make them much more competitive at least in terms of power and CO2 outputs compared to say, BMW. At the moment, there is no comparison, the Germans hold all the trumps.
MA is currently being worked on for JTDs. The 2.0 JTD twin turbo is already used in the 9-5, the Insignia will get it soon and Fiat cant afford to be left behind when every one else is going the multi-turbo route. As the 2 turbo version exists already it would be madness NOT to MA it and only MA the single turbo. And anyway MA AND 2 turbos would be even better than MA or 2 turbos alone.

The Germans are going great, but Mitsubushi is overlooked-their 1.8 TD has 2000bar common rail, is all alloy and has variable valve timing, it makes 150PS/221LBS/FT, not bad for a 1.8. Dont think BM's diesels, however good they are (and they are) use VANOS at all . . . yet.



Like it or not 2 turbos are the way the industry is going-Fiat and BM got there first (on 4 cyl engines) with their "23D" and JTD twin turbos, VW was slow, but now has a twin turbo 2.0 (not using it on passenger cars yet but will do soon).

And 2 turbos have transformed the 6 cyl diesel market, BM started, then Merc and now VW have followed suit-all 3 are locked in a power battle and VW's recently launched 2 turbo diesel 6 pushed it to 309PS/480LBS/FT BMW upped the figs on theirs to match.

Mercedes showed an SLK with a TRIPLE turbo version of their 3 litre diesel (third turbo sat in the V I think) and an SL with a 5 litre V8 diesel back in 2005. Dunno why theyve taken so 'kin long, but theyll be launching a triple turbo 3 litre soon.

Pity they never had the balls to build the diesel SL (would have been easy as it was a production engine) and pity the diesel SLK thats just gone on sale is only a 2.2 4 cyl . . . but it DOES have 2 turbos and makes amazing torque for its size (369LBS/FT !!), you can also get this engine in the S CLass now !

The PSA/Ford/LandRover/Jag diesel engine joint venture uses 2 turbos on the V6s and the V8s. The 2.2 4 uses 2 turbos as well, in all its guises (though theyre all underpowered-the highest output is 177, which cant even match BM's 2.0 single turbo!).

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Originally Posted by phil-gtv6 View Post
the tuning boxes for the Lancia Delta TT JTD offer 230bhp & 335lbs, and that's with no other mods (DPF ect), so some good potential
Exactly, a proper remap, exhaust and I/C mod would see around 300PS/450LBS/FT. I know you can see 283 odd PS with the GTB2256v (or whatever its called) from the 2.4, but I bet its more laggy than 2 turbos.

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Originally Posted by yan.ko View Post
Btw2. Turbo is one of the most strained component on the turbocharged engine. I still don't know why would anybody mess up with freefloat + wastegated turbos instead of one quality VNT one on 1.9JTD.
All the more reason to split the load it takes between 2 units, rather than have one take it all !
Maybe you should write to Fiat Powertrain, BMW, VW Goup, PSA/Ford/Jag/Landrover etc and tell em theyre wasting theyre time with 2 turbo set-ups Yan.ko ? ! lol

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Exactly, a proper remap, exhaust and I/C mod would see around 300PS/450LBS/FT. I know you can see 283 odd PS with the GTB2256v (or whatever its called) from the 2.4, but I bet its more laggy than 2 turbos.
Jeeez, wake up and make some calculations what pressure the turbo will need to develop to push air enough for 300HP into 1.9 diesel engine (not talking about smoky racing mods with low AFR)

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All the more reason to split the load it takes between 2 units, rather than have one take it all !
Maybe you should write to Fiat Powertrain, BMW, VW Goup, PSA/Ford/Jag/Landrover etc and tell em theyre wasting theyre time with 2 turbo set-ups Yan.ko ? ! lol
Of course they offer and develops such things. Because they are making money on it. More components they put into, higher the car and servicing costs paid by user. Easy ;-) It's up to everyone to think a bit about what is reasonable and what not. I prefer simple and effective design rather than 3 turbo setup and steam turbine recuperating exhaust gas heat like BMW developed, or any expensive technologies saving 2% of fuel and 5% emissions, OMG.

Btw. As I already said, sequential two-turbo setup makes a sense on inline engine, but according to my knowledge of turbo compressors, not in case of such small engine as 1.9JTD is. Sure it does on 3liter and we can talk about 2.4l.

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I dont know what got into you to become so bi-turbo happy... but I think it is time to let it go... it is not worth it. 100%... In theory it is great but in practice you will be much happier with GTB2056V or similar turbo.

The only thing bi-turbos are good for, is spool at very low revs... but cars fitted with bi-turbo have gearboxes, DMFs and driveshafts that can handle this. Your 147 will not benefit much, because you will have to limit the injection in low revs to keep your drivetrain in one piece.

And stop dreaming about 300BHP with that bi-turbo. You would need well over 3.5 bar absolute boost pressure @4000rpm. And then you have to burn around 130mm3/inj of fuel to get 300BHP. It would never be able to handle that. EVER...

Even 250BHP is an optimistic figure.
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I ll probably go the GTB2056v route on cost grounds.

But gonna have to dis-agree with you (in the nicest possible way ) 2 on the 2 turbo front-2 turbos are better than 1, end of and their use in more and more 4 cyl engines proves it.

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Originally Posted by yan.ko View Post
Jeeez, wake up and make some calculations what pressure the turbo will need to develop to push air enough for 300HP into 1.9 diesel engine (not talking about smoky racing mods with low AFR)


Of course they offer and develops such things. Because they are making money on it. More components they put into, higher the car and servicing costs paid by user. Easy ;-) It's up to everyone to think a bit about what is reasonable and what not. I prefer simple and effective design rather than 3 turbo setup and steam turbine recuperating exhaust gas heat like BMW developed, or any expensive technologies saving 2% of fuel and 5% emissions, OMG.

Btw. As I already said, sequential two-turbo setup makes a sense on inline engine, but according to my knowledge of turbo compressors, not in case of such small engine as 1.9JTD is. Sure it does on 3liter and we can talk about 2.4l.
Theres someone on here that has a GTB2056v and is making 283 PS (with print out), so I m going by that yan.ko.

As for the suggestion that manufacturers are only using 2 turbos cos theyre making money on it, well thats just silly-theyd actually make more money if they re-mapped a single turbo simply cos they could charge the same and be spending less on components.

The 3 turbo set up was for a V6, not a 4 and it had one big one per bank, plus a small one shared at low speeds. And the steam turbine thing was a great idea, as long as it doesnt weigh too much-why waste all that energy ? !

Its all about minimising lag and getting better response and one big one, even with VGT/VNT is never gonna spool as quick as a small one.

And Tribesman surely the gearbox and driveshafts wouldnt be able to handle a GTB2056v if they couldnt handle 2 turbos, either ?

Plus how do you explain the 283 PS jtd 16v with the GTB2056v ?

And if most of the current multi turbo diesels in production are anything to go by, peak power rpm will go up to nearer 5000.
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283PS with GTB2056V is just a very optimistic dyno... nothing else. With 3 bar pressure, the realistic figures with GTB are up to 250BHP. That is if you want relativerly smoke free every day car. You can make more, if you dont mind the smoke, but 280bhp is out of the question.

About gearboxes... the highest strain on gearbox and DMF is high torque in low revs (1500rpm or even below). You can easily destroy the gearbox with GTB, and that is not the fastest spooling turbo, so whats the point of using turbo that offers more boost in low revs if you are unable to use it?
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2 turbos is a fine idea, but why would you want to use 2 **** turbos (like on the Saab/Lancia) when you could use just one good one (like the GTB)?

Typos - 2 turbo set-up would be great if thats what you want but the two used by Lancia/Saab are old technology, so to get the best out of your set-up you'd want to change them for something better.
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