Turbo Upgrade Advice for X5 50i

[J44 X5]

I have a 2011 BMW X5 50i, and am thinking about doing a minimal turbo upgrade - something like Stage 1 or Stage 2 Pure which use the OEM housings.

Looking for some advice on what the best turbos would be to use, and what supporting mods would be necessary. I wouldn't be interested in maxing out the potential of the turbos, just looking for around a 50 to 100 increase in Hp and torque.

The vehicle is stock except for Dinan Stage 2 software.

What issues would there be if upgraded turbos were installed and no other modifications were made? Would the Dinan Stage 2 be compatible or would a retune be required?

[Sophisticated Redneck]

Originally Posted by J44 X5

I have a 2011 BMW X5 50i, and am thinking about doing a minimal turbo upgrade - something like Stage 1 or Stage 2 Pure which use the OEM housings.

Looking for some advice on what the best turbos would be to use, and what supporting mods would be necessary. I wouldn't be interested in maxing out the potential of the turbos, just looking for around a 50 to 100 increase in Hp and torque.

The vehicle is stock except for Dinan Stage 2 software.

What issues would there be if upgraded turbos were installed and no other modifications were made? Would the Dinan Stage 2 be compatible or would a retune be required?

What psi does the Dinan stage 2 hit? My understanding is the stock turbos are good to 21psi. I have the ESS tune that is hitting 15psi in stage 1, and 18psi stage 2. I have a jb4 to install to max it out but have not done so yet.

[J44 X5]

Originally Posted by Sophisticated Redneck

What psi does the Dinan stage 2 hit? My understanding is the stock turbos are good to 21psi. I have the ESS tune that is hitting 15psi in stage 1, and 18psi stage 2. I have a jb4 to install to max it out but have not done so yet.

I'm not sure. I plan to email Dinan today to find out, and also get their advice on upgraded turbos.

My thinking was that with a minimal turbo upgrade, I could achieve the extra power without increasing boost pressure and be at a higher efficiency and reliability range compared to pushing the stock ones close to their max pressure.

[J44 X5]

Dinan technical support said that their Stage 2 software is an extra 2 psi over stock. That seems very low to me, especially considering that you said the difference between the ESS stage 1 and stage 2 alone is 3 psi.

They also said that Stage 4 is 3 psi above stock, but requires their intercooler. They did not know the stock boost pressure right off hand.

[mitch808]

Originally Posted by J44 X5

Dinan technical support said that their Stage 2 software is an extra 2 psi over stock. That seems very low to me, especially considering that you said the difference between the ESS stage 1 and stage 2 alone is 3 psi.

They also said that Stage 4 is 3 psi above stock, but requires their intercooler. They did not know the stock boost pressure right off hand.

The thing is, boost is not the end all be all power adder. all the fueling and ignition timing also make a difference. Dinan also is trying to make sure it's reliable over some more aggressive tunes that don't offer warranties and such.

[Sophisticated Redneck]

Originally Posted by J44 X5

Dinan technical support said that their Stage 2 software is an extra 2 psi over stock. That seems very low to me, especially considering that you said the difference between the ESS stage 1 and stage 2 alone is 3 psi.

They also said that Stage 4 is 3 psi above stock, but requires their intercooler. They did not know the stock boost pressure right off hand.

Boost is dependent on elevation and ambient temp but what I have monitored on mine at 1400 elevation is stock boost maxes at 8psi during winter and 12psi during summer. I monitor it through the torque app and also gave dual boost gauges with their own pressure sensor so I can keep an eye on boost differential and the refresh rate is much much quicker then the ob2 apps.

When I installed the ESS tune, stock boost was maxing at 10.5psi (ambient temps were in the 80s). And right after was hitting 15psi. Their stage 2 you have to run and octane booster or mix of race gas for 94aki.

[Sophisticated Redneck]

Originally Posted by J44 X5

Dinan technical support said that their Stage 2 software is an extra 2 psi over stock. That seems very low to me, especially considering that you said the difference between the ESS stage 1 and stage 2 alone is 3 psi.

They also said that Stage 4 is 3 psi above stock, but requires their intercooler. They did not know the stock boost pressure right off hand.

Their intercooler setup looks nice but $$$$, I just installed the Alpins intercoolers I picked up off eBay for the cheap, look to be identical to the M's and are about 30percent bigger then stock. You have to massage the alternator bracket with a Dremel a bit to get them to fit but otherwise drop right in.

[Sophisticated Redneck]

Originally Posted by mitch808

The thing is, boost is not the end all be all power adder. all the fueling and ignition timing also make a difference. Dinan also is trying to make sure it's reliable over some more aggressive tunes that don't offer warranties and such.

True and ESS is the same, when I asked them for the stage 2, they made sure to make it clear it requires 93+ gas or bad things will happen. When I asked them about using the jb4 on top, they confirmed Stock turbos will max a 21 but it's pushing the system to it's limit and not recommend. They are alot like Dinan and tune for longevity.

[J44 X5]

So who could provide a tune for a minimal turbo upgrade?

Does anyone know if the stock engine can reliably handle 50 to 100 more hp and torque than Dinan Stage 2, and if that is achievable with a small turbo upgrade on 92/93 octane gas? And would any supporting mods be required?

[Thecastle]

So boost is not the right measurement to ask about, pressure is a measure of the resistance to flow.

What you want to know is what your mass airflow is, iat, timing and fueling. Increasing MAF, lowering IAT, advancing timing and burning all that air is key.

Turbo's need upgrading when they ratio of exhaust back pressure/boost pressure is > 1. In that case you're leaving power on the table due to too much back pressure. The other scenario is that your having to run the turbo outside its efficiency range to achieve your Mass air flow targets. But you'll only know this with logging.

In general increasing turbo size means higher rpm's before your achieve full boost. Aka higher boost threshold (most people call this lag). They become less drivable around town, because you need more airflow through the engine to spool the bigger/heavier turbo compressor/turbine.

You're 1st upgrades after a tune should be to lower intake restrictions /exhaust backpressure, especially exhaust.. Every psi of exhaust back pressure your can reduce is free hp.

Anytime you increase engine output you decrease engine life, there is no free lunch. But of course does the reduction matter to you? Lots of folks have pushed over 600-700hp out of the n63, but if you plan to race the car I'd say its not gonna last long. But the extra hp only wears the engine faster if you use it.

[Movado750]

So you think by adding catless downpipes this effected the turbos. to much spooling?