[bigjim]

This may be a stupid question but having spent 8.5 years in a 1.6 petrol 147. How do you drive a 2.4 diesel properly? What's the best way to get economy? and what's the best way to make it move as fast as it'll go.

 

[Cuore_Sportivo_155]

best economy, upshift early and avoid boosting. read the traffic and road ahead and don't use the brakes
most go: redline it.

 

[Arcangel_SPN]

Sell your 2.4 and buy a giulietta 1.6 JTDm .....best for economy

Enviado desde mi Aquaris M5 mediante Tapatalk

 

[richydraper]

Practise smoothness the 159 doesn't seem to like being chucked around. But it can quite happily get on with it If driven right.

I'm in a similar position coming from a 1.6 Stilo. Economy is in early up shift... 30 in 4th or 5th. 40+ in 6th. Only hook first when stationary.

Speed is only an available option 'on boost' I shift between 3500 and 4000 revs and make quick shifts. You'll be into licence losing territory pretty quick.

 

[bigjim]

cheers chaps.
the day i got it i went faster between two roundabouts than the 147 could go flat out. didn't realize. it doesn't seem to stop as readily as the 147, i'm putting that down to the weight of the 159 battleship. when i get my indy to service it, i'll get him to give the breaks the once over, may need your brembro numbers for disks and pads.
loving the look of her. my mates at work have named her Monica, after Monica Bellucci. Good for her age and looks lovely from the front.

 

[JabawokJayUK]

Don' bother redlining the 2.4 as it's pointless. Change at about 3.5 to 3.75K or 4K at the latest. Their is no torque left in the standard torque curve by that point in the RPM so your just putting less power than you have available through the gear you're in vs if you shift and go back down to 2K and get full torque in the next gear. Power band is between 2K & 3.75K in a standard unmapped 2.4. <2K is still EGR open so air is dirty, and the DPF slows the turbo spool so realistically you wont see proper power till 2.2K or 2.5K. If you get the DPF removed, and the EGR blanked as well as a good remap your max available torque starts at about 1750rpm through to 3500rpm so you get more usable power. Helps economy too as the low down torque means you can cruise everywhere <2Krpm and still be making good pace using minimal fuel. Boost is irrelevant in this equation as boost is only air so effects the amount of air available for the target AFR. The VNT will discard unused air to regulate this so if yuour boost is at the top of the gauge it doesn't necessarily mean your at max power. The total amount of fuel being injected is based on RPM and that is what effects economy and power. Obviously throttle position is a key factor here as well as the ECU uses this to determine "what the driver wants" and adjusts.

As for the brakes, they need to be upgraded to be useful. forget disks its all about the pad and stock pads are shocking. Autolusso have a deal on Performance Friction Pads (£100 quid fitted I believe) which are by far the best pad available for this car. But... best upgrade over stock is braided lines and TYP200 fluid as well. The 2.4 suffers heavily from brake fade if you push her and its down to the standard rubber brake lines heating up and expanding as much as the pads fading. If you need disks I (and many others) can recommend MTEC disks. Cheaper than OE and very very good. Grooved, Vented & Drilled/Dimpled can be picked up with colour treatments to prevent centre hub rust for very low money.

 

[Cuore_Sportivo_155]

Boost is never irrelevant as it also means EMP and that means pumping losses. same as unnecessary revs means hydrodynamic friction losses in the bearings.

Torque delivered by the engine has to be multiplied by the gear ratio to get the wheel torque. Very often it's beneficial to rev in a lower gear beyond the point of max power, as in the next gear the available torque is about 30% less. The 210 bhp makes at 4500 rpm in standard tune the same bhp as at 2600 RPM. no reason upshifting unless you'll be above 2600RPM in the next gear. For the 200bhp engine 3000RPM in the next gear is the shift point. For my giulietta it's actually 3200 rpm, and the TCT obviously knows this as it has no problem revving to and beyond redline before upshifting. Things change after a remap though.

 

[JabawokJayUK]

Boost is never irrelevant as it also means EMP and that means pumping losses. same as unnecessary revs means hydrodynamic friction losses in the bearings.

True but the losses in efficiency in the 2.4 are negligible given its direct rail & VNT architecture. The point being made was trying to use the boost needle as a reference for economy is a pointless activity as the VNT mechanism alongside the MAP will manage actual vs required airflow.

Torque delivered by the engine has to be multiplied by the gear ratio to get the wheel torque. Very often it's beneficial to rev in a lower gear beyond the point of max power, as in the next gear the available torque is about 30% less. The 210 bhp makes at 4500 rpm in standard tune the same bhp as at 2600 RPM. no reason upshifting unless you'll be above 2600RPM in the next gear. For the 200bhp engine 3000RPM in the next gear is the shift point. For my giulietta it's actually 3200 rpm, and the TCT obviously knows this as it has no problem revving to and beyond redline before upshifting. Things change after a remap though.

Interesting that you state the 210 with the 2056 has a solid torque curve to 4500rpm? I have not personally observed this in any of the 2.4 210 maps I have looked at, can you show me how you have got to this reference point please?

The reason I ask is here is the torque limitation map from a stock 2.4 210. As you can see peak is at 2250rpm with a short drop and steady hold to 3500rpm before it falls. by the time you hit 4500rpm you have approximately 250nm of torque vs 450nm at 2250rpm. If you really want to split hairs you have about 400nm of torque at 4000rpm so could shift at that point but it falls off a cliff from there.

Yes, the gear to torque ratio is important here but in reality, changing at the red line in is pointless in a diesel. Petrols that make all the power at the top end however its the only way to drive them.



Please note that in the image, the white line is a stock map, vs the red line that is an aggressive remap.

 

[Cuore_Sportivo_155]

I didn't say solid, only that bhp at 4500 rpm is the same as at 2600 rpm:

http://www.squadra-tuning.nl/cms/domainfiles/1/product/122/96.gif black numbers and line are unmodified maps

and as measured by rvcorse:http://www.rvcorse.nl/wp-content/uploads/2013/06/159-24-JTDm-210pk.pdf

Both point out that you're better off in lower gear at 4500 rpm than a higher gear at 2600 rpm or below. You'd have to overlay the gear ratios to find the shift point which would be different for every gear. Also don't forget the torque limit in 2nd gear, so you might just want to stay in 1st longer.

 

[JabawokJayUK]

I didn't say solid, only that bhp at 4500 rpm is the same as at 2600 rpm:

http://www.squadra-tuning.nl/cms/domainfiles/1/product/122/96.gif black numbers and line are unmodified maps

Err, not sure what you're seeing in that image that I am not as it supports the map image I posted. @ 4500rpm you have 250nm of torque. and at 2600rpm you have 420nm of torque....

So your assertion that you have the same torque at 4500rpm that you do at 2600rpm is wrong. You have roughly 400-450nm of torque throughout the range from 2250 to 4000rpm as depicted in your dyno run and the actual ECU map that the engine uses to produce the power.

This supports the shift point assertions I made in my post to the O/P's question. Like I mentioned before this is starting to feel like an unnecessary debate splitting hairs and what is starting to feel like a one-upmanship....

Sorry, just re-read a couple of points..... you are discussing BHP in relation to a diesel engine which is a pointless measure. Torque is the only useful thing to discuss in relation to power in a diesel. So while I accept your assertion that BHP is the same at both RPM points, its a useless measure.

To that end, this is my last post on this matter. There is a reason I don't visit AO much anymore.....

 

[Cuore_Sportivo_155]

You can't see torque seperate from rpm, (in this case at the wheels) so it's easier to work with bhp. Bhp at the wheels = bhp of the engine - drivetrain losses, regardless of gearing.

You could calculate the actual torque at the wheels for every gear at a certain rpm, but it's a very roundabout way to arrive at what the BHP number is already telling you.

No matter what gears you're talking about, below 2600 rpm you're better off in a lower gear for outright performance. the narrower the gap between the gears, the closer you'll have to stay to the max bhp figure for shifting so at higher gears with maybe 20% gear ratio difference, you'd be best off changing somewhere between 4000 and 4500 rpm, going by the suadra figures. That way you're back with 210 bhp at the wheels, while changing at 4000 will only give you just over 200.

I'm sorry that you don't understerstand the relationship between torque and bhp thoroughly, but it is what it is. Certainly no reson to feel one-upped. And that certainly wasn't my intention.

 

[Philjay50]

I love these discussions, and so many acronyms, facts and figures and stuff. I know absolutely FA about diesel turbo engines, I know that mine goes like S**t off a chrome shovel after an Alfatune remap BUT the MPG is not great no matter what style I drive. What I can say is that to drive one of these things "with spirit" as my dear old Mum would say is a sure fire way of losing your licence. I still prefer petrol tho'.

 

[kandlbarrett]

The only thing that gives acceleration is thrust. Thrust is directly related to torque and gearing.

I would always want to know the torque curve and gearing to calculate best change up points for maximum acceleration because from that you can calculate torque at the wheels and therefore thrust in each gear at varying RPM. That, for me, is true for both petrol and diesel.