Tuning T-Jet 120hp 'Chip-tuning'

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Tuning T-Jet 120hp 'Chip-tuning'

Let's not go further off-topic here, I was a customer at my dealership from before I had a Fiat and there's a reason I bought a new car there. If that reason is wrong I'll see soon enough with my luck.

The message is: talk to your dealership, it's indeed probably a good idea to have in writing chiptuning isn't a problem before you do it.
 
Last Thursday got to the dealer. They don't do remapping themselves but the do it like Isabella said via Squadra Tuning. Theoretically this will end my warranty. BUT technically!!! if anything happens they wont say to Fiat that ECU files are remapped or changed. I won't get this in writing but they are pretty flexible with this...
I have better idea, please say my where i can be wrong. A small story with worst case scenario:
1. I go for remap on warranty and engine or gearbox blows (the most expensive things which can go wrong)...
2. instead of directly going to dealer service first i deliver my car to the chip tuner to put stock soft.
3. with original soft i go to the dealer and they don't see anything unusual...

if ECU block was not open and safety seal is there then dealer service can do a thing? it's a bit of safety... which can cost extra transport charges and that's it...

Another worst scenario if something happens on the foreign road where i would be forced to go to not to my dealer nor able to put original soft. then i am f'ed...

Yeah, oil and ALL filters i will change in end of december on 25k. and with 15k interval in the future for all filters except for interior filter (every 30k). Timming belt a good note. On 60k mark i will ask mechanic to check it. My warranty ends in 2019 January or 100k whatever comes first.

1&2 gears are the worst... the start is lagging, more torque there needed!!!. like kia picanto or whatever smallest cars with 0.8l engine are better in normal conditions (not drag racing just normal start). i am just embarrassed with my car because of that...

And extra torque on 4&5&6 will be beneficial in the city as well. as on a fifth 55km\h can pull it off alreaady but with extra would be nicer. 3 gear i have no complains. it goes up to 130km\h and ok accelartion from 1800rpm...
 
PS: does someone check oil temperature on highways above 140km/h? does it go above middle mark? I speak here about oil temperature and not water temperature.
 
Be careful with using too much torque at low rpm in high gear. The M32 box is notorious for failing bearings at 5th and 6th gear.
"Economy driving" kills gearboxes, you need to save a lot of fuel to earn one of those back!

At 55km/h I am cruising in 4th while my Doblo's gearbox ratios are a bit shorter than your Tipo's, and the reason Squadra is working on my 2nd and 3rd gear performance is because I always want to be in 3rd up to at least 70km/h under acceleration (now I often pull hard to 60 in my limited 2nd and shortshift to 4 because my 3rd is worthless).
I don't use 6th before 90km/h and I never accelerate in 6th.

My motto is: If I'm cruising below 90km/h and my "shift up" indicator isn't showing on the dash, I'm in a too high gear.
I cruise at 2000-2500rpm (up to 90, then I run out of gears), accelerate at minimum 2500rpm, 3000+ when I'm in a hurry.

I've driven the Tipo T-Jet, if you want torque at 55km/h you need to be in 3rd, 2nd even if you are in a hurry.
I was like you when I first had my Doblo T-Jet: I've had diesels and unblown petrols before, it doesn't behave like a rev happy unblown petrol at all so I drove it like a diesel.
In fact it's really in between. It doesn't like 5+k rpm like an NA petrol (due to tame camshafts and the tiny turbo running out of puff), but for the love of your engine and gearbox, don't diesel it either, the gearbox starts really low and has 6 gears for a reason.


Like I've said, I've driven the Tipo T-Jet, personally I didn't find it that slow despite it was a well equipped wagon, much better tuned from the factory than my Doblo for sure.

It's probably not what you want to hear, but based on my experience with Fiat and my driving impressions of the Tipo T-Jet I recommend you to wait until about a year and a half and 45k km before you chiptune it. You'll never get written approval from your dealer as this could cost them their dealership, it's up to you to decide when you'll take the risk of trusting their spoken words.
Meanwhile make a habit of driving more in the mid-rpm range and ignore the shift indicator (it's there for economy and emissions, not for performance or reliability!) instead of dieseling it.
Yes it'll consume a bit more fuel, but if you'd push more torque out of it it'll drink more as well.

Don't forget: yes it has 120hp and 200+Nm at low rpm that can be increased via chiptuning, some even modify it to squeeze well over 200hp/300Nm out of it, but it'll always be a little economy 1.4l 4 banger that's lugging a heavy car around, mated to a gearbox that doesn't have the best reputation.

Greetings from Belgium,
Isabelle
 
Last Thursday got to the dealer. They don't do remapping themselves but the do it like Isabella said via Squadra Tuning. Theoretically this will end my warranty. BUT technically!!! if anything happens they wont say to Fiat that ECU files are remapped or changed. I won't get this in writing but they are pretty flexible with this...
I have better idea, please say my where i can be wrong. A small story with worst case scenario:
1. I go for remap on warranty and engine or gearbox blows (the most expensive things which can go wrong)...
2. instead of directly going to dealer service first i deliver my car to the chip tuner to put stock soft.
3. with original soft i go to the dealer and they don't see anything unusual...

if ECU block was not open and safety seal is there then dealer service can do a thing? it's a bit of safety... which can cost extra transport charges and that's it...

Another worst scenario if something happens on the foreign road where i would be forced to go to not to my dealer nor able to put original soft. then i am f'ed...

Yeah, oil and ALL filters i will change in end of december on 25k. and with 15k interval in the future for all filters except for interior filter (every 30k). Timming belt a good note. On 60k mark i will ask mechanic to check it. My warranty ends in 2019 January or 100k whatever comes first.

1&2 gears are the worst... the start is lagging, more torque there needed!!!. like kia picanto or whatever smallest cars with 0.8l engine are better in normal conditions (not drag racing just normal start). i am just embarrassed with my car because of that...

And extra torque on 4&5&6 will be beneficial in the city as well. as on a fifth 55km\h can pull it off alreaady but with extra would be nicer. 3 gear i have no complains. it goes up to 130km\h and ok accelartion from 1800rpm...

I can't comment on this other than to say that it sounds like conspiracy to commit fraud to me which is an offence in the UK even if the actual fraud never takes place. Getting involved in any way could make me liable to prosecution.

I'm not a lawer, but know enough to see this is questionable and not to get involved. Call me paranoid but it's too late once it happens.

Robert G8RPI.
 
That's exactly why no dealer will ever approve modifications in writing and why I had my LPG conversion, intake, boost gauge, and even side window wind deflectors fitted by the dealership that sold me the car.
That's also why I recommend giving it some time and kilometers to work out potential issues under warranty before changing anything in the ECU, and why I only remove limiters instead of also adding performance (this would be tax and insurance fraud).
 
It's not that simple: say you have a misfire... or problems with cold starts..or whatever crappy small problem... what do you do then?
Do you first remap it back to stock? then take it for diagnosis? (then they won't be able to diagnose it)
Take it to the dealer... and hope they don't check it?

What do you do if it blows up on the road somewhere? tow it to the tuner, wait for a 1-2 days until then can remap it to stock (because when things like this happen it's usually at the most inopportune time, and the tuner might be away, or have equipment problems or other things), then tow it to the dealer?


My recommendation: if you want the tune NOW just accept loosing the warranty(with a small chance of having them fix it, under warranty).
If you're not willing to loose it, then just enjoy the car, drive it like you stole it!

BTW a looser(more km) engine takes more power better/safer : has already been through numerous heating/cooling cycles (so any stresses in the metals would be normalized), any problems should have already shown up/gotten fixed, the engine has been fully broken-in/mechanical run-in ..etc
 
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My motto is: If I'm cruising below 90km/h and my "shift up" indicator isn't showing on the dash, I'm in a too high gear.
I cruise at 2000-2500rpm (up to 90, then I run out of gears), accelerate at minimum 2500rpm, 3000+ when I'm in a hurry.

In fact it's really in between. It doesn't like 5+k rpm like an NA petrol (due to tame camshafts and the tiny turbo running out of puff),

I only use the 6th gear over 120km/h...and it's done 200k on without bearing replacement, 5th over 80km/k... and i try to minimize acceleration in those gears.
Just rev it more! (oil pressure will be better, more protection for the engine)

Replace the turbo with the vl36, now mine revs all the way up.. to 6.5k... nice and linear.. almost not drop in torque (i am talking about actual feeling, on the dyno graph it's evident :) ) BUT you do loose some of the low down torque.. mine feels basically NA until 2000rpm :).. but it's so rev-happy now ... it's worth it!
 
Totally agree on that, not only oil pressure, but the water pump, alternator, aircon pump... Everything is just spinning in a much happier range, the engine also spreads the torque over more power strokes per second, and you're not trying to push all the torque you've got through a tall gear of a box that is a known weak spot just to go from a 50 to a 70/80 zone.

The 90km/h I'm mentioning is in my Doblo with shorter gearing, 90km/h in 6th is about 2400rpm and that's strictly for cruising on cruisecontrol, when I can't drive a perfect constant 90 I'm in 5th and when I need some power I go to 4th.
I can't entirely remember the ratios of the Tipo I tested, but I do remember 6th being WAY too tall for 90km/h cruising even if I wouldn't care about the mechanics and ignore everything I know about lugging the engine.
Like I said, there are 6 gears for a reason, it's not to be already in 5th at 55km/h.

I won't do the VL36 on my Doblo: Belgium is really strict when it comes to upgrades to the point it's impossible. It's really ridiculous.
F.e.: You can have an intake system that breathes through an existing vent/scoop, and you can add or open up fake air intakes in the bumper/bonnet/fenders, but you can't have an intake system breathing through a vent/scoop that wasn't originally on the car.
If it weren't for that, I'd have a TD04 on it, but the closest I'd ever get to owning a legal T-Jet here would be to get an Abarth or a Bravo 150.

But if upgrading the turbo (and camshafts) is legally an option I would definitely recommend that over chiptuning to squeeze 250Nm at diesel rpm's out of the little 1.4 and VL37.
 
You could get away with the vl36.. it's virtually identical to the stock vl37.
The only differences are:
-Internal compressor/cold side is 5mm bigger.... i had both side by side.. couldn't tell the difference.
-it says vl36 on it..
you could get around this by modifying the vl37 compressor housing to accept the vl36 compressor wheel... basically take it to a specialized turbo shop.. they can do it.
So it will look 100% stock.. only way to tell would be to actually measure a stock one and the modified one side-by-side.



You would need a tune if you change the turbo and/or cams.
 
Yeah, I know, and I considered doing the turbo mod + NA cams when its time for the timing belt, but then there's the cost of doing that + getting it from almost France to Squadra to have it tuned...
Price/performance gets a bit ridiculous then and it still is a daily driven Doblo that will probably see nothing but all-season tyres and stock suspension parts for all its life (with me anyways), so I decided it's smarter to just release the choochoo the stock hardware can put out safely for many many years on LPG fuel and enjoy it as is.
 
ok, guys! it's not consipracy... just an idea. if i do chip, i will never mention it here. no evidence of result, no harm..

Gearbox fragile on higher gears on low rpms? really? i am not afraid to put extra rpms on the engine, i know no harm will be done by that. but harm to gear box by adding torque on higher gears wiht low rpms?
what's the connection between gearsize/rpm/torgue? is theere less torgue on higher rpms then? there will be the same ammount of torque if i do full throttle on 3500rpm.
has someone has any theory on this? --> this sounds like conspiracy and no substantiation...
 
The thing is, when you accelerate higher in the rpm range, you'll be massively breaking speed limits if you'd do that in 5th or 6th, you'd be in 3rd or 4th depending on the speed.
The M32 gearbox tends to fail because the bearings on the 5-6 side on the shaft that contains 1-2-5-6 are its weak spot. By throwing torque at it in 5th and 6th you're creating heat right where those weakest bearings are, so on top of all the reasons why it's better to keep the engine in a happy mid rpm range, that's why it's bad for the box as well.
Nothing conspiracy about that, you don't have to believe us, just Google the M32 gearbox.

Also don't forget wheel torque is a result of engine torque and gearing. My Doblo is extremely limited in 3rd and delivers full power in 4th, yet a 50-70 acceleration in 3rd is still faster than in 4th because of the gearing, and it's even faster in 2nd despite the turbo noticeably runs out of puff somewhere around 60 on top of that same limiter.
A diesel has strong internals and a lot of raw torque all the way down around 1500rpm, which it loses throughout the rev range so fast that it compensates the gearing advantage around the 3.5k rpm mark.
The T-Jet 120 engine only reaches that point at about 5k rpm but doesn't have the raw torque and heavy duty internals, so lugging it around 1800rpm is pretty much as bad (both performance and reliability) as racing a diesel at 4500rpm.
 
I will google the gearbox to see what exactly you mean. Thanks!

Peter, dont agree here. Time and distance are related together in parabola. If i do 30k in half a year it means my filter the same dirty as i did 30k in a year, because i spend about the same time after all. My average speed is ~45km/h all year around.
didnt you notice that flow through vent decreases significantly when filter is dirty?
 
didnt you notice that flow through vent decreases significantly when filter is dirty?

No, I don't, (still I drive about 30.000 km's a year, and change that filter once a year, and I use a special Bosch carbon filter...)
In fact, most interior filters are NEVER changed at all.
My father in law bought a new Toyota Corolla :)yuck:) back in 2004, and he thinks changing that interior filter is a waste of money, so it wasn't changed until last year, when it was completely black and filled with sooth etc.
He didn't notice any difference with the new filter, as he told me, so now he is even more convinced that it's just a marketing trick to get extra money from customers...
 
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... even faster in 2nd despite the turbo noticeably runs out of puff somewhere around 60 on top of that same limiter....

I'm going to try to explain what you are feeling:
-as i've said before the ecu limits boost in the lower gears, by using the boost controller solenoid
-in 1st,2nd and a bit in 3rd the max boost is limited:
-1st ...0,1bar
-2nd...0,2bar
-3rd...0,5bar
-4th,5th,6th...0,8bar
The values are MAX values, approximately accurate(i had graphs of the boost in each gear...can't find them)
In each gear the boost graph raises to max, holds a bit, and then falls back down to the top of the rev range... you might think it's the turbo.. but it's actually the ECU => boost solenoid =>wastegate =>lower turbine pressure=>lower boost.
You can actually see this by using graphs on MES.

There are numerous reasons why it's programmed that way, but in short it comes down to reliability (gearbox and engine) and efficiency.

So the idea is that the tuner can still raise the pressure twords the end of the rev range.... but it requires careful motorization, while tuning, on a dyno.. checking temps, knock, oil pressure, AFR...etc

Again.. for reliability they set it up so you wouldn't want to rev it over 5.5k (where the boost/torque really falls down)... if it doesn't feel good, people will not rev it that high=> longer life =>less chances of repairs under warranty and generally people considering the engines more reliable.
The behavior in the higher revs can be drastically changed by only upgrading to the VL36 turbo... it feel so much better now. Basically the cam shafts don't matter that much on a turbo car....where they might feel better is in the lower revs, just before the turbo kicks in; and of course in the higher revs it could make more power with lower boost... so more efficient.
 
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Peter: I have to be brutally honest, I've changed the filter at 30k/1yr as part of the official maintenance, the one that's in it now will do a whole lot more than that! (Not 12yrs though, YUCK!)

aurick86: What I ment was that my Doblo clearly goes beyond the most efficient rev range at about 60km/h in 2nd as the turbo doesn't help along anymore, but that it's still pulling to 70 faster than it does in 3rd because of the gearing advantage.
I wouldn't be surprised that the ECU indeed cuts off boost at lower rpm than the turbo would run out of flow if the wastegate was disconnected, but according to what tuners get out of it at the top there really isn't that much left anyways.

There is no difference between 2nd and 3rd in my Doblo stock: immediate 0.2bar* boost rising to 0.4 at about 3.5-4.5k rpm and afterwards backing out again.
1st is now releaved of its torque limiter and reaches slightly higher values, 2nd and 3rd will be brought to the levels of 4th and up (immediate 0.7bar* boost up to 4.5k rpm) hopefully soon.
I don't rev much over 5k rpm anyways as at that point my LPG ECU switches back to petrol.

*According to my analog boost gauge.
 
As far as I know, Fiat dropped the M32 for the Tipo and are using the C635 (with 6-speed) and C510 (with 5-speed).

Yes, you are correct. Also C635 goes with Automatic Dual Clutch (DDCT) transmission. It promises 350Nm of max torque. So, my mind issues with 'weak' gearbox are irrelevant. it's a tough one.

Also, according to this source, this 1,2,5&6th gear are on the lower shaft. Which makes Isabelle correct. Since, max possible torque is massively higher than t-jet engine can produce, i would say it's save to accelerate on the 6th gear. Other wise we are also not allowed to accelerate on the 1st and 2nd too ;)

You may say that speed of the shaft on the higher gear is different which heats up bearing as well. how come we still can drive it 120km/h and above normally?

http://www.autolusso.co.uk/gearbox-C635.html



I tried to look for this gearbox problems and couldn't find any. Can't say that M32 box has the same strength...

However, if you have 1.6 multiair diesel 120hp, i would chip it very cautiously as it already has 300Nm of torgue, with chip it will go to the red zone....
 
If you indeed have the C635 gearbox you don't need to worry about the issues with M32 indeed.
Accelerating in 1&2 is indeed on the same shaft as 5&6 in the M32, but the forces on the selected gears are away from the weak bearings and away from the final drive, spreading the heat and load better. Also the torque is limited in 1 and 2, and even if you remove that ECU limitation you're still not likely to use all the torque at low rpm in those gears.

Fact is the T-Jet isn't a diesel, nor a high revving NA petrol, it's in between and that's how it should be driven to keep it happy. Not only is the engine much happier to deliver power above 2500rpm, it is also spreading the force over more power strokes per time and the oil and water pump are pumping better as well.
 
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