General Multijet Turbo upgrade

[puntofato]

Greetings everyone,

I am thinking of purchasing a VNT turbo from an Opel Astra 1.3CDTI to fit to my Panda. The engine is the same (compression ratio and displacement) and I don't think I would have a problem with the extra air going in.

The reason I want to do this is because I hate it when it is under 2000rpm and the turbo doesn't spin enough to push me around like other diesels with bigger engines. For instance when climbing a hill it does cut under 2000rpm and it is annoying.

I think the VNT will spin much faster and efficient from low rpm and that might improove my mpg cause the diesel engine relies on its turbo to get good results. When under 2000 it just tries to accelerate using more fuel.

I will have the turbo during the week. I know a guy who imports these parts from Germany and I shouldn't have a problem testing if it fits properly on my car.

Feel free to tell me what you think about my idea.

 

[The Beard]

Try the website of Angel Tuning. They will remap for up to 50% (105bhp). They will even return it to standard tune if you so wish for free. The cost is about £325 inc. VAT but send them an e-mail via the link on the web site to confirm this. They even include a home visit for this price.

 

[Highlander]

If my memory is correct that turbo takes the Astra up to 90bhp. I'm told that the Panda Petrol and Multijet share the same gearbox, if this is the case you may find you have far too much torque for the box

I have often wondered at Fiat not producing a model with a higher output. At present I believe you get the punto multijet with 75 bhp and 90 bhp.

Tara Ian

 

[puntofato]

I don't think that petrol and diesel Panda have the same gearbox. There is massive difference in torque and the gear ratio is different. There is an issue concerning the endurance of the gearbox after the upgrade but I don't think that it would be that much.

Anyway I have to get the turbo in my hands first and see if it fits properly. I will let you know.

 

[oilrag]

I'm told that the Panda Petrol and Multijet share the same gearbox, if this is the case you may find you have far too much torque for the box

Thats what I was thinking.
I seem to remember the 1.3 Multijet in the Panda being tuned to develop less torque from new due to the gearbox.

( compared that is with this engine in other applications in the Fiat range)

 

[oilrag]

I don't think I would have a problem with the extra air going in.

Feel free to tell me what you think about my idea.

I just realised you are newish to the forum, so welcome

There are several techs here who I`m sure will give better advice than me.

But for me, I dont think you can just bolt another different turbo on and not have big problems.
IMHO, its just a charecteristic of the engine that you need to stay above about 2,000 revs for the torque and smoothness to be there. ( although peak torque is less than that)

Its going to really pull well at 2,000 revs on hills so it could be just a matter of adjusting your driving style.

We have one of these engines in a Punto van and its great if you dont let the revs drop below about 1,800 revs on the change. ( it feels smoother at 2,000)

I think there is no way around the pre turbo torque as thats a function of engine capacity and its only a 1.3.
For example, we have a non turbo 1.9D Punto as well as the 1.3 multijet. The 1.9 is faster away over the first few yards due to its bigger cylinder capacity, but the 1.3 Multijet leaves it dead in the water after that as the turbo kicks in.
Regards

 

[D4nny8oy]

Bolting on a bigger turbo won't necessarily give you more power. The standard map only allows for approx 2000mbar of boost (1bar), anything over this and it shuts down to limp-home mode (we had many problems with faulty pressure sensors incorrectly reading 2500mbar causing this).

In fact, in most cases a bigger turbo creates more lag and less response, needing more revs to spool-up. Forgive me but unless this new unit has a roller-bearing core I can't see the point? If it were to spin-up quicker, would it fall outside the range of the standard map leading to a lean situation?

All 1.3 mJets have a unique gearbox which as far as I'm aware will be the same as the Vauxhall unit due to the whole powertrain being a joint venture between the two manufacturers.

The 75 Bhp version is a dinky little turbo with the actuator operating the waste-gate directly (no overboost valve).

From memory, the 90 Bhp model has a slightly larger compressor housing and uses the same variable-geometry vane technology as in the 1.9 Jtd (with an overboost valve).

 

[alfanige]

WHOA!!!! you will need the ECU remapped to suit the turbo or it will run like a bag 'o' ****e. Try a remap first, as we have cured many a 1.3 with it (including our own, which are running awesomely now!), if it doesnt do what you want, we put it back to standard and its a FULL refund so at least you can try it and not lose any money

 

[Toomanytoys]

Hi Any chance of a couple of power graphs to show the change from stock?
what affects does it have on mpg?

Have to agree.. small turbo = spin up quick and large turbo = loads of lag.. remap sounds like an option..
When I had a corsea on hire the owner said it was a real pain to do a clutch as it had an adapter plate.. maybe an early euro spec corsa (Was belgium)

 

[Ade911]

Hi guys.
I'm new here and new with Fiat's Before I had Audi a3 1.9 tdi witch was mapped. I wanted to ask what is standard rpm for turbo to spool in full? I have grande punto 1.3 and I feel that turbo spools around 2.5-3k rpm.

 

[The Beard]

Looking at my earlier post in......2007......eee, where did the years go? I first looked into uprating my Panda MJ but was put off by being told, as mentioned by oilrag and puntofato, that the torque capacity of the MJ gearbox is 150nm while the engine puts out 145, so there is very little room for more of the twisty stuff. Puntos,as standard, have higher torque output so presumably the 'box will be able to take much more.

So might not be much of a problem with the Punto, but unless you have the latest generation of Panda then I'd be tempted to let sleeping dogs lie.

 

[Sweetsixteen]

Of course, the torque load on the gearbox depends on the weight of your right foot.
If you increase the maximum torque of the MJ 1.3, then it does not mean that you will definitely overload the gearbox.
A wider spread of increased torque is always useful, and can be enjoyed without putting any more load on the box than a standard engine. Common sense when driving, whatever the peak torque, is what gives the whole drivetrain a long life.