[mygarbage2000]

Hi guys. First off let me say that team-bhp is the best thing to happen to me since CM/FM. It's almost as addictive and about a hundred times more useful. The kind of effort the whole community puts into this is amazing and humbling. Specially guys like GTO, Mclaren, Samurai, Psycho and others - you know who you are.

I owe a big thanks to the community for helping me decide on my 2nd car - The Black Magnum 2.0 LT. Your reviews and ownership reports cemented my decision after my test drive which just blew me away. Have now done 18500 kms with it since December 26th, 2008 when I bought it, and each one of them has been amazing. However, the 'keeda' is back and I want to make it even better than it already is.

OK, so I am going to put down my assumptions and questions here. Would really appreciate you guys helping me out in trying to understand how this may or may not work. And correct me if I am wrong wherever I am.

Requirements

1. Want to remain within GM tested limits for the block so suggestions of a bigger after market turbo/ remap are not what I am looking for. Also, want to keep all this reversible for the future.

Assumptions

1. The Captiva/Cruze/Magnum use the same VM Motori RA 420 SOHC engine
2. The Captiva/ Cruze use a VGT while the Magnum uses a FGT
3. The ECU and turbocharger if replaced with the Captiva/ Cruze's should be enough to get me to the 148/320 or 150/320 of those engines.

However, this seems far too simple and I am sure there is a catch somewhere. So now the questions.

1. Are these assumptions correct?
2. The ECU control of VGT vs. FGT. Will the ECU type need to be changed or a Flash/modified version will do?
3. What about plumbing? Is the spec different? Bigger pipes for the VGT?
4. And wiring?
5. Is the Captiva spec turbo, which as far as I know is a Garrett GTB1549V (please correct if you have better info) available from Garrett directly or is it better to source it from GM. As far as I know, it is not in the current Garrett catalog. Available from Chinese guys but I don't know about their reliability.
6. Has anybody done/ thought about this before?
7. What am I forgetting?
7. How naive am I being?

And finally, can someone help me do this? Imagine the end product with a remap on top of the mods. 180/ 400 sounds very doable to me if this gets off the ground. All your time and help will be greatly appreciated. Thanks a lot guys.

[dadu]

Originally Posted by mygarbage2000

Assumptions

1. The Captiva/Cruze/Magnum use the same VM Motori RA 420 SOHC engine
2. The Captiva/ Cruze use a VGT while the Magnum uses a FGT
3. The ECU and turbocharger if replaced with the Captiva/ Cruze's should be enough to get me to the 148/320 or 150/320 of those engines.

However, this seems far too simple and I am sure there is a catch somewhere. So now the questions.

1. Are these assumptions correct?
2. The ECU control of VGT vs. FGT. Will the ECU type need to be changed or a Flash/modified version will do?
3. What about plumbing? Is the spec different? Bigger pipes for the VGT?
4. And wiring?
5. Is the Captiva spec turbo, which as far as I know is a Garrett GTB1549V (please correct if you have better info) available from Garrett directly or is it better to source it from GM. As far as I know, it is not in the current Garrett catalog. Available from Chinese guys but I don't know about their reliability.
6. Has anybody done/ thought about this before?
7. What am I forgetting?
7. How naive am I being?

And finally, can someone help me do this? Imagine the end product with a remap on top of the mods. 180/ 400 sounds very doable to me if this gets off the ground. All your time and help will be greatly appreciated. Thanks a lot guys.

I dont know if your assumptions are correct or not as I havent studied the Turbo's of Captiva/ Cruze/ Magnum, but going by your assumptions the ECU map for a FGT and VGT is very different and will not work by just swapping the Turbo.

But going by the model no GTB1549V

GT- Garrett
B- Bearing type
15 - Inducer diameter
49 - Exducer diameter
V- Variable

In simple words this unit is a bearing type variable turbocharger that has a GT15 frame size turbine coupled to a 49mm (exducer diameter) compressor wheel.

What are you forgetting/ naive about :

- What's the application, racing or city driving
- Selection of the turbo is done keeping in mind the target HP
- Mass air flow and Pressure ratio has to be mapped to the compressor for fitment
- Air filter, Oil supply to Turbo, wastegates etc have to mapped and calculated.

If you go into the specifics there's a lot of calculation behind it for a correct fitment.

The Turbo experts here can guide you through it or use the search.

[mygarbage2000]

Originally Posted by dadu

I dont know if your assumptions are correct or not as I havent studied the Turbo's of Captiva/ Cruze/ Magnum, but going by your assumptions the ECU map for a FGT and VGT is very different and will not work by just swapping the Turbo.

Thanks for the reply dadu. I know that simply swapping the turbo will not work. The query was about the ECU. Is the ECU the same type as that in the Magnum and therefore can just be reprogrammed with the new parameters or is it an ECU swap job?

Originally Posted by dadu

- What's the application, racing or city driving
- Selection of the turbo is done keeping in mind the target HP
- Mass air flow and Pressure ratio has to be mapped to the compressor for fitment
- Air filter, Oil supply to Turbo, wastegates etc have to mapped and calculated.

If you go into the specifics there's a lot of calculation behind it for a correct fitment.

- The application is city and highway driving. Unfortunately for us Delhi residents, there is no track to go to.
- Choosing the Captiva's turbo was the result of the assumptions made. If it is as complex as installing any other turbo, then it becomes an exercise in futility. I would imagine that there is part sharing between the Captiva and the Optra/ Lacetti and therefore the other parts would not be that different. However, this is pure conjecture and I stand to be corrected on this.
- The idea was to use the Captiva's settings/ parameters as those things would already be mapped in the factory installation. Again, correct me if I am wrong.

This post was meant to evaluate the feasibility of such a project in comparison to a clean, after market install. If it is considerably easier and less likely to go wrong, then it is a worthy aim to pursue. Again, thanks to you guys for your help.

[Akshay1234]

you want the captiva power on a magnum? the easiest way is a tuning box and its reversible and on stage 2 of the box you can get about 160bhp and 375nm+ if you also have a performance air filter.

[mygarbage2000]

Originally Posted by akshay1234

you want the captiva power on a magnum? the easiest way is a tuning box and its reversible and on stage 2 of the box you can get about 160bhp and 375nm+ if you also have a performance air filter.

Hi Akshay. Thanks for the reply. Yes I am aware of that but if you see my post, that is not what I am looking at. The turbo will not only increase power but the VGT will mean that the driveability will increase throughout the rev band. Also, it will be withing GM spec for the engine. If a tuning box has to be added, it can be added after the conversion as well which will take the power into the 180ish range.

The point is, the engine is capable but crippled in the Magnum. Why not use the engine to its spec limit? And specially if it is not a complicated process.

[Jaggu]

If its the same block, one can try upgrading but cost involved might not justify the same. Turbo+ECU+wiring+Injectors (assumption)+Plumbing = $$$$$$$

Try getting the part numbers and see how much of these will require replacement.

[Psycho]

VM Motori S.p.A.

This link points to be a simple addition but I am sure that there will be a need to replace the wiring harness, VGT Controller in addition to the turbo, its manifold and the ECU (have not been able to find info on the injectors though).

It is not going to be a simple / cost effective approach to getting there, it would be better to stick to the tuning box as Akshay mentioned.

[brraj]

Two best options i can think of is

1) Install tuning box for magnum as mentioned.
2) Enjoy peted magnum for another 2years till the chevy cruze rates come down to 7-8lakhs and buy a second hand cruze. simple and reliable.

[mygarbage2000]

Originally Posted by Psycho

VM Motori S.p.A.

This link points to be a simple addition but I am sure that there will be a need to replace the wiring harness, VGT Controller in addition to the turbo, its manifold and the ECU (have not been able to find info on the injectors though).

It is not going to be a simple / cost effective approach to getting there, it would be better to stick to the tuning box as Akshay mentioned.

Really? The wiring harness and the Manifold as well? I want to be sure about this. Is there any way to get my hands on a service manual for both the Optra and Captiva? That will have the specs for all the parts I am assuming.

What do you think the cost in total for all these parts would be assuming all this has to be done? The turbo cost I have got is around $200. Will a re-flash of the Optra ECU work or will the ECu have to be replaced?

@brraj - Actually if GM starts a trade-in program for the Cruze, I'll be the first one in line.


I don't want to put this to rest till I find out the details. I should know both options fully well before I decide to go down one route.

[cooldude1988765]

Are you sure the turbo is only $200, if so that is pretty cheap.

[brraj]

Found a guy who can do this for you, but he is expecting 2 lakhs. Let me know if you are serious about it.

[Ramsagar]

+1 to akshay.First Pete the magnum, if not satisfied with the power then go for RD ecu both together & see.That should bring you close.

[greatmana2000]

Technically it is possible , but it wont be really useful .

A car is designed with a lot of factors in mind and similar is the engine .
Even if you are sucessful with the engine ,there are so many other factors like the gearbox , clutch , drive shaft etc .

I am sure the gearbox and the clutch are uprated and the gear ratios are totally different for the cruze . The torque of the cruze must be way higher ( assumption) than the magnum .

The cooling system will also be different and the sensors used might also be different .

[vinaydas]

i think only the captiva has VGT and cruze has a FGT.

[cooldude1988765]

Cruze also has vgt since it is 150bhp