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Gary, ASE Certified Technician
Category: BMW
Satisfied Customers: 675
Experience:  Senior Technician
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Wanted to know if I can turbo charge my 2012 bmw 128i,

Customer Question

wanted to know if I can turbo charge my 2012 bmw 128i
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: nothing so far, just doing some reshearch
JA: Anything else you think the mechanic should know?
Customer: it has the n51 engine
JA: How many miles are on the car? Is it an automatic or a manual transmission?
Customer: 54,000 miles automatic
Submitted: 1 month ago.
Category: BMW
Expert:  Gary replied 1 month ago.

Hi there,

Depends on many factors.

How much money do you have to spend?

How much power do you want?

How long does the engine, transmission and rear axle need to last?

With the engine in standard form, the compression ratio is already fairly high, so it would only take about 5psi of boost safely.

7-10 psi would be possible with more tuning and water/methanol injection.

As you may be learning, for each 20hp, the price goes up exponentially.


Customer: replied 1 month ago.
I would like to get it up to around 330hp if possible, would $10,000 be enough, and I would like to keep it for 4 yrs or so
Customer: replied 1 month ago.
just doing some research, to see if its possible and economical to do something like this, if not then i'll take a friends advice and get a fox body mustang and roll with that, but I like my BMW's
Expert:  Gary replied 1 month ago.

If you find a shop in your area that can do this sort of job, I would say that would be possible.

For 330 hp, it would be forged pistons at 7.5 :1 or so, ported cylinder head, full engine balance, fuel system upgrade, ecm dyno tune etc.

I would worry about if the transmission would be up to the task.

I'm not trying to spend your money here, so if you like a Mustang, then you can get WAY more power per dollar out of it.

If the BMW is in good condition, why not keep it stock, and get another car to hot up.

Hope this helps.


Expert:  Gary replied 1 month ago.

Hello again,

I hope my advice has been of assistance to you.

Kind regards