[bradsm87]

N55s have been around for nearly 9 years now and there are still so few mild turbo upgrade options with both compressor and turbine upgraded. We only have the choice of "Stage 1" turbos with a far from ideal huge compressor to turbine size ratio then next step up is "Stage 2" monsters with absolutely monstrous compressors and big clipped turbines aimed for huge power.

We need something to fill the void between these options. There are good 9-blade Garrett-style 57mm inducer / 50.6mm exducer turbine wheels available for the N55 turbo now - A perfect option for a milder "Stage 2" upgrade turbo when paired with the right sized compressor.

Someone needs to offer this. I don't think people know what they're missing in terms of insane response and capable of making great power on low boost. I've been looking out for something for years.

[harkes]

Stage2.......monstrous......

Stage2 is a fine stage1 in my book. There has to be some solid gains from changing a turbo.

[bradsm87]

Originally Posted by harkes

Stage2.......monstrous......

Stage2 is a fine stage1 in my book. There has to be some solid gains from changing a turbo.

Yes monstorous in the little stock housings. Just take one look at the difference in compressor inducer. This is the issue with this platform. People are content with the very limited options because they don't know what they're missing.

A little smaller wheeled version of existing Stage 2 turbos with full unclipped Garrett-style turbines would be absolute response monsters and still max stock HPFP. Existing Stage 2 turbos do lose that initial snappiness in D mode in Auto cars at low RPM. It doesn't have to be like that.

Such a turbo would have very "solid gains" for PWG owners and smaller gains for EWG owners (similar to gains from Stock PWG to Stage 1).

[harkes]

Originally Posted by bradsm87

Yes monstorous in the little stock housings. Just take one look at the difference in compressor inducer. This is the issue with this platform. People are content with the very limited options because they don't know what they're missing.

A little smaller wheeled version of existing Stage 2 turbos with full unclipped Garrett-style turbines would be absolute response monsters and still max stock HPFP. Existing Stage 2 turbos do lose that initial snappiness in D mode in Auto cars at low RPM. It doesn't have to be like that.

Such a turbo would have very "solid gains" for PWG owners and smaller gains for EWG owners (similar to gains from Stock PWG to Stage 1).

Isn't the entry level Speedtech what you are asking for then?

[HKD126]

Speedtech kit with the EFR 7064 is what you want.

[enjoythemusic]

Dinan is a 'tween size.

[enemigo13]

TTE460 is what you need, it has gains over stock ewg turbo and will max out stock hpfp.

Originally Posted by bradsm87

N55s have been around for nearly 9 years now and there are still so few mild turbo upgrade options with both compressor and turbine upgraded. We only have the choice of "Stage 1" turbos with a far from ideal huge compressor to turbine size ratio then next step up is "Stage 2" monsters with absolutely monstrous compressors and big clipped turbines aimed for huge power.

We need something to fill the void between these options. There are good 9-blade Garrett-style 57mm inducer / 50.6mm exducer turbine wheels available for the N55 turbo now - A perfect option for a milder "Stage 2" upgrade turbo when paired with the right sized compressor.

Someone needs to offer this. I don't think people know what they're missing in terms of insane response and capable of making great power on low boost. I've been looking out for something for years.

[bradsm87]

Originally Posted by HKD126

Speedtech kit with the EFR 7064 is what you want.

I am RHD so it won't fit. Also needing something 100% stock appearing.

[bradsm87]

Originally Posted by enjoythemusic

Dinan is a 'tween size.

That's just a Stage 1 with stock sized turbine any way too big compressor for that stock sized turbine.

[bradsm87]

Originally Posted by enemigo13

TTE460 is what you need, it has gains over stock ewg turbo and will max out stock hpfp.

Clipped stock turbine

[M-terkait]

pure turbos already fully spool 20psi at 3k rpm, you want it fully spool at 2k? lol buy V8

[bradsm87]

Originally Posted by M-terkait

pure turbos already fully spool 20psi at 3k rpm, you want it fully spool at 2k? lol buy V8

Everybody does different things with their cars. This is my wife's daily driver. It's not a sports car. If it was an M235i, I would definitely choose the PS2.

It's a big heavy car with an automatic transmission. You definitely lose the snappy responsive throttle feeling that the stock car has in D mode with the PS2. It's not about the RPM at which it reaches full spool. It's about transient response, how quickly it responds to sudden throttle changes.

[lens]

Originally Posted by bradsm87

Everybody does different things with their cars. This is my wife's daily driver. It's not a sports car. If it was an M235i, I would definitely choose the PS2.

It's a big heavy car with an automatic transmission. You definitely lose the snappy responsive throttle feeling that the stock car has in D mode with the PS2. It's not about the RPM at which it reaches full spool. It's about transient response, how quickly it responds to sudden throttle changes.

Throttle can be changed with a tune.

If you legit want full spool at 2k, prepare to fork out money for broken parts as low end power/torque will break things.

[bradsm87]

Originally Posted by chaungo

Throttle can be changed with a tune.

If you legit want full spool at 2k, prepare to fork out money for broken parts as low end power/torque will break things.

It's not throttle position or valvetronic response. It's boost response to sudden changes in boost request.

As I said earlier, it's not about RPM threshold, it's about the turbo's transient response. Low RPM boost threshold is good too of course. 13psi by ~2300 would be great. Plenty of people do a lot more than that with stock turbos. With safe timing, that is certainly not damaging to anything. It's when people try and get 20psi as early as possible with bulk timing that breaks things.

[lens]

Originally Posted by bradsm87

It's not throttle position or valvetronic response. It's boost response to sudden changes in boost request.

As I said earlier, it's not about RPM threshold, it's about the turbo's transient response. Low RPM boost threshold is good too of course. 13psi by ~2300 would be great. Plenty of people do a lot more than that with stock turbos. With safe timing, that is certainly not damaging to anything. It's when people try and get 20psi as early as possible with bulk timing that breaks things.

That's the thing though, people do alot more than that with stock turbos, but it doesn't mean you're not gonna break anything. I have 112k miles on my F30 335xi right now, with PS2 which has been on for the past 30k miles. I abuse my car almost daily, and even bring it to the track to do lapping and its fine because all the power is up top and i'm not launching the car on the dragstrip consistently. If I had stock turbo or the such and did alot of drag or so, I'm pretty sure things would break quickly. Low end power is pretty useless as it would be only good for launches, however, too much and all you'll do is spin which would render it useless again, just look at the when the M3/M4 first came out.

[bradsm87]

Originally Posted by chaungo

That's the thing though, people do alot more than that with stock turbos, but it doesn't mean you're not gonna break anything. I have 112k miles on my F30 335xi right now, with PS2 which has been on for the past 30k miles. I abuse my car almost daily, and even bring it to the track to do lapping and its fine because all the power is up top and i'm not launching the car on the dragstrip consistently. If I had stock turbo or the such and did alot of drag or so, I'm pretty sure things would break quickly. Low end power is pretty useless as it would be only good for launches, however, too much and all you'll do is spin which would render it useless again, just look at the when the M3/M4 first came out.

Again, transient response is the goal, not breaking out in wheelspin. I've got torque limits per gear to control 1st gear wheelspin anyway. Yes the RPM threshold will still be low but limited to 13-14psi so it's not going to be breaking out in wheelspin giving it a quick squirt in 4th lol.

There is a perfect mid-way point in there for me hence why I don't want to keep the tiny stock PWG turbo but I don't want a PS2 either. Enlarged turbine is just as important as enlarged compressor though. I'm not interested in a "Stage 1" compressor upgrade only.

[enemigo13]

Originally Posted by bradsm87

Clipped stock turbine

what’s the drawbacks of clipped turbine? later spool up? anyway i’ve seen good dyno results using this turbo (460+ crank hp). about ps2 - fully agree, it’s a bit too much considering how weak stock fuel system is. along with ps2 you should upgrade hpfp also, and together it’s quite a lot of $.. I’m not big fan of tons of extra wiring under the hood, meth controllers, meth tanks etc.. good if you can have power on pump gas or sometimes mix a bit of e85 for keeping octane high. just a metter of taste

[bradsm87]

Originally Posted by enemigo13

what’s the drawbacks of clipped turbine? later spool up? anyway i’ve seen good dyno results using this turbo (460+ crank hp). about ps2 - fully agree, it’s a bit too much considering how weak stock fuel system is. along with ps2 you should upgrade hpfp also, and together it’s quite a lot of $.. I’m not big fan of tons of extra wiring under the hood, meth controllers, meth tanks etc.. good if you can have power on pump gas or sometimes mix a bit of e85 for keeping octane high. just a metter of taste

The issue is more that it's still got a stock sized turbine, not so much that it's clipped. Clipping does help increase flow but a bigger turbine is a much better option. Bigger diameter gives more leverage and more blade area. Better both for transient response, boost threshold and exhaust back pressure.

[harkes]

Define "full spool" makes a bit of a difference whether we talk 10-15 or 20psi + from what rpm in what gear...maybe an electric car is what you want. Full spool at all rpm

[bradsm87]

Originally Posted by harkes

Define "full spool" makes a bit of a difference whether we talk 10-15 or 20psi + from what rpm in what gear...maybe an electric car is what you want. Full spool at all rpm

I mentioned a few times that boost threshold is not the main issue. It's transient response mostly.

I simply want the right turbo for my needs. A ~5mm bigger turbine and a ~3mm bigger than EWG compressor (~8mm bigger than PWG) would be pretty spot on. There is a very big jump between stock turbine and PS2 and an in between option would be really great for a lot of people's needs. I don't really get what's hard to understand about that.

I'm pretty close to just buying a used EWG turbo and MEVD172G and considering it close enough. Not ideal but better than what I have and with EWG, it's easier to tune and I can use a MPPK tune as a starting point.

[harkes]

Originally Posted by bradsm87

I mentioned a few times that boost threshold is not the main issue. It's transient response mostly.

I simply want the right turbo for my needs. A ~5mm bigger turbine and a ~3mm bigger than EWG compressor (~8mm bigger than PWG) would be pretty spot on. There is a very big jump between stock turbine and PS2 and an in between option would be really great for a lot of people's needs. I don't really get what's hard to understand about that.

I'm pretty close to just buying a used EWG turbo and MEVD172G and considering it close enough. Not ideal but better than what I have and with EWG, it's easier to tune and I can use a MPPK tune as a starting point.

I have some turbo theory reading to do I can tell. There is noticeable lag with the PS2 - had it only been a ball bearing model...

[bradsm87]

Originally Posted by harkes

I have some turbo theory reading to do I can tell. There is noticeable lag with the PS2 - had it only been a ball bearing model...

It's way more to do with the wheel sizing and design than the bearing type. If ball bearing made that much difference, more cars would come from the factory with BB turbos.