General Twin turbo 1.9 JTD

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General Twin turbo 1.9 JTD

The Beard

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Just wondered if anyone saw the road test in one of the major car mags this week of the latest Saab 9-3 diesel with a 177 bhp 1.9 Tid (JTD) twin turbo engine. Is this the first showing of this engine in any car or is there a FIAT group vehicle on the UK market somewhere that I haven't seen yet?
 
i don't understand how twin turbo is benefical on a 4 cylinder diesel. we have varible geometery turbos now, so having a small turbo for quick spool up and a larger one for high end power isn't needed anymore. one VGT will do. and it's not like there's two banks either :confused:
 
According to a copy of "Quattroroute" magazine I picked up while on holiday in Italy earlier in the year, the 180 bhp model will be available to other makers ie. Vauxhall/Opel, Saab and Cadillac as well as FIAT, the 190 bhp model will be reserved for the three main FIAT group brands. The same magazine described the engine as using the small turbo at lower revs for quick response and good low speed torque, while the larger one will be responsible for higher revs and higher power/torque. This is obviously more complicated (and more expensive?) than the variable geometry turbo but as the competitors produce more power the Italians must feel they have to respond.
 
My Stilo doesnt really stop acclerating until it gets to about 4200rpm just before the redline, but i dont like to push it that much so always upchange at around 3500rpm :D

unless im driving for economy and its 2200rpm lol (y)
 
This discussion seems to be going nicely, but, how about this? Does a Bravo, Focus, Golf et al. really need a 180 or 190 bhp diesel engine? I can see the thinking behind this sort of power output for a 159 as it comes up against the 3-series, A4 and the like it'll need that sort of power and torque. There's always the possibility of an Abarth diesel Bravo of course, but would a car with this engine need traction control and other aids therfore pushing the price up until it starts to get a little too close to the 159 and its ilk?
 
You certaily have got a point here. But the ideas behind these high powered engines is that in some key markets the demand for powerful engines is there regardless of the size (within reason) of the car.

People want to have performance and comfort but also demand low fuel consumption. The smaller the engine, the less drag is pushing up fuel consumption. The more power can be extracted at low rpm the more mpg. Also smaller units mean less weight and the smaller dimensions mean engine compartments can be designed accordingly.

The new PSA (Peugeot/Citroen) CEO comes out of the aviation industries. His goal is to make cars rather smaller than bigger and reduce the weight considerably in order to maintain fuel consumption figures at low levels and have the little creature comforts demanded as well as performance.
 
Interesting you should mention weight. So long as you don't make it too light. If you remember, the early Citroen AX s had problems on the Motorways in cross winds because, according to certain journalists, they were too light. But, weight is an important consideration. If aerodynamics are extremely important to economy and performance at high speeds, then weight is the enemy of low speed acceleration and fuel consumption. On that basis I don't understand why more manufacturers don't follow the lead of Renault with the last Clio in using more and more plastic in body construction, the front wings of that car were, if you remember, made out of that material. So long as the basic structure is strong enough, then with the possible exception of the doors, the rest of the body could be made of material that does not rust and would be lighter than steel. It's possible they could be self coloured at the factory and if you wanted a replacement panel it could come ready "painted". Flexible panels would also be less liable to minor impact damage.
 
This discussion seems to be going nicely, but, how about this? Does a Bravo, Focus, Golf et al. really need a 180 or 190 bhp diesel engine? I can see the thinking behind this sort of power output for a 159 as it comes up against the 3-series, A4 and the like it'll need that sort of power and torque. There's always the possibility of an Abarth diesel Bravo of course, but would a car with this engine need traction control and other aids therfore pushing the price up until it starts to get a little too close to the 159 and its ilk?

With the demand for remaps upto 200bhp.. I'd say the answer is yes :D
 
This discussion seems to be going nicely, but, how about this? Does a Bravo, Focus, Golf et al. really need a 180 or 190 bhp diesel engine? I can see the thinking behind this sort of power output for a 159 as it comes up against the 3-series, A4 and the like it'll need that sort of power and torque. There's always the possibility of an Abarth diesel Bravo of course, but would a car with this engine need traction control and other aids therfore pushing the price up until it starts to get a little too close to the 159 and its ilk?

Golf has a 170bhp diesel engine :confused:, people want more power for ease of driving etc

With the demand for remaps upto 200bhp.. I'd say the answer is yes :D

Thats exactly the point i was going to make :D
 
A bit late in the day to send this, but I've had use of an Alfa 159 S.W. 1.9 150bhp for three days. Far more stylish than a 3-series and C-class. The car cruised well on motorways and had good levels of roadholding, although its handling was not quite up there with the BMW, the design and Italian style more than made up for it in my opinion. But the main reason for posting this is that the performance, in my view, was more than adequate. Not startling, but certainly enough for my needs. Slower vehicles on the A59 from Clitheroe to Skipton were "dispatched with alacrity" as motoring magazines might say and gave an average fuel readout of 41 mpg. For me, the level of performance was fine, but I would expect it to be better in the Bravo as it must be lighter. The fact I've used terms like, "in my opinion", "in my view" and "for my needs" perhaps means I've answered my own question about the amount of power and torque needed in an engine. Maybe the higher output engines should be reserved for a Bravo Abarth JTD should one ever appear, after all there are Golf GT TDi s and 3-Series diesel Sport models.
 
Look what I have dragged up from the depths...

My friend in the auto business raised this very point today. The twin-turbo on the 9-3 TTiD is supposedly a direct bolt-on replacement for the single turbo on JTDs...

Now, that sounds too easy for my liking so does anybody else have any ideas/thoughts?
 
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