n55 vs n55HP - How do we get that extra power and torque?

I see that the N55HP has 13 more hp and 30 lb/ft torque vs the standard N55 in our F10. The N55hp comes in the 2012 and newer: F12 (6-series), F21 (1-series) & F01 (7-series).

Anyone know exactly how this power is achieved and if we can buy some OEM parts to obtain the extra power and torque of the N55HP?

15hp is not really a noticeable difference, not sure why you want to do that.
If you want more power, the best bet is a tune.
I highly recommend the N55 Burger tune I have in my car. It's +50hp and +80 torque for $500 bucks. The power is night and day.

Originally Posted by smashhell

15hp is not really a noticeable difference, not sure why you want to do that.
If you want more power, the best bet is a tune.
I highly recommend the N55 Burger tune I have in my car. It's +50hp and +80 torque for $500 bucks. The power is night and day.

+1...goes to show you the tunes are not that aggressive to being with as the cars have some bandwidth.

Originally Posted by smashhell

15hp is not really a noticeable difference, not sure why you want to do that.
If you want more power, the best bet is a tune.
I highly recommend the N55 Burger tune I have in my car. It's +50hp and +80 torque for $500 bucks. The power is night and day.

50hp for $500 is just delicious. Gonna have to get that at some point.

Originally Posted by DieselNY

50hp for $500 is just delicious. Gonna have to get that at some point.

At $395 the Stage 1 tune is quite good too. You'll be surprised. It is upgradeable to the Stage 2. You just trade-in the module, and make a few wire modifications.

I guess my thread turned into a BMS tune infomercial . The point of this thread is not to get into a debate about TRUE power gains with piggyback tunes. I simply want to know how the power gains are had with the N55HP.


From my past experience, these slight power gains were often had from tweaked intake and exhaust manifolds. Of course with FI (forced induction) vehicles, all it takes is a little programming and or an increase in boost.

I'm curious about this as well. I posted in the F12 Forum the question of what the N55HP has that's different from the N55 that gives it that little extra boost in power.

What I'm really curious about is how much REAL power it has over the N55, as the N55 is very underrated (at 280 RWHP putting it around 330-340 actual crank HP).

Originally Posted by BigDeep1

I guess my thread turned into a BMS tune infomercial . The point of this thread is not to get into a debate about TRUE power gains with piggyback tunes. I simply want to know how the power gains are had with the N55HP.


From my past experience, these slight power gains were often had from tweaked intake and exhaust manifolds. Of course with FI (forced induction) vehicles, all it takes is a little programming and or an increase in boost.

I would think it's the latter since it is very economical to do from the factory. But it would be interesting to get the details. Maybe it's similar to the 335 BMW performance upgrades from the dealer.

Originally Posted by K-A

I'm curious about this as well. I posted in the F12 Forum the question of what the N55HP has that's different from the N55 that gives it that little extra boost in power.

What I'm really curious about is how much REAL power it has over the N55, as the N55 is very underrated (at 280 RWHP putting it around 330-340 actual crank HP).

How are you calculating that... lol 330-340??? You add 10%-12% which puts you right at 310. Not arguing with the number just your calculation.

I am hoping to dyno my car some time next week or two - time permitting. Then I will throw on the stage 1 (If I can ever get it back from my deadbeat friend bigdeep) Then I will post some numbers.

BigD - I believe the answer to your question is going to be software. I tried searching for you, but everything just says "fine tuning" This to me indicates that perhaps it was nothing mechanical.

I agree with Miami. Its just a software tweak. When you're dealing with a turbo'd car a simple addition of 1-2 psi can get you that additional 15-20 HP.
And I am glad too see that smash has came to a realization of the true HP increase of the N55 BMS tune.

Originally Posted by BigDeep1

I see that the N55HP has 13 more hp and 30 lb/ft torque vs the standard N55 in our F10. The N55hp comes in the 2012 and newer: F12 (6-series), F21 (1-series) & F01 (7-series).

Anyone know exactly how this power is achieved and if we can buy some OEM parts to obtain the extra power and torque of the N55HP?

BMW Performance has a Power kit for the 3- and the X5/X6 N55 that bumps power to the 40i/N55HP level (20hp, 32lbft). Kit is an ECU tune, auxiliary water cooler and an enhanced radiator fan. There is also a kit for the TTV8 (50i, 40HP and 80lbft).

I have no idea of why this Power kit has not been offered for the F10.

I have the power up kit in my 2011 335 - although the #s are low as far as increase it completely changed the car. Torque is very low and pulls hard to redline -also seems to build boost much faster. Looking to do Dinan on new 535 when they finally come out with it.

Originally Posted by miamiboyca

How are you calculating that... lol 330-340??? You add 10%-12% which puts you right at 310. Not arguing with the number just your calculation.

I am hoping to dyno my car some time next week or two - time permitting. Then I will throw on the stage 1 (If I can ever get it back from my deadbeat friend bigdeep) Then I will post some numbers.

BigD - I believe the answer to your question is going to be software. I tried searching for you, but everything just says "fine tuning" This to me indicates that perhaps it was nothing mechanical.

From what I've "learned" in Dyno testing, RWD Auto cars generally see 15-20% drivetrain/etc. loss by the time it gets to the rear wheels. 10-12% is very efficient (not sure if that's even possible on an Auto?).

There's a dyno sheet I recently saw that said a "general rule is to divide by .xx(number). When I did that, it came out to roughly 20% drivetrain loss.

Also, if you look at the 535i's consensus trap speed in the 1/4 mile, being around 100 MPH (give or take depending on various tests), and weighing at about 4,000 lbs, it shows that it should pin it right at around 340 HP.

A good basis I like to use is a car I used to be involved with in terms of HP/Track times, which is the SN-99 Mustang GT. It was a very pure basis of how RWHP and track times equate.

For example: The 5 Speed Manual 2004 GT made 225 RWHP on the money, which would put it at 260 HP on the money. The Auto version of the same car sucked out an additional 10-15 RWHP, putting them generally at around 210 RWHP. Those cars weighed at around 3200-3300 lbs.

The Manual GT did exactly a 14 Second 1/4 at 100 MPH, those two numbers perfectly aligning with each other as a good power/weight ratio VS track time/MPH ratio (same exact numbers the 535i generally does).

So, if you have a 3200 lb GT making 225 at the wheels with only little drivetrain loss due to being a Manual and doing a 100 MPH trap speed, and then add 700-800 lbs to it (i.e now making it a 535i) then you'd have your trap speed dropped to 92-93 MPH (1 MPH for ever 100 lbs). Therefore, in order for the 535i to recapture that 100 MPH trap speed AND taking into consideration it's an Auto tranny which means it has even more drivetrain loss, you'd need at least 80 more HP, putting it at 340 crank HP (since the GT has 260 crank HP and does the exact same numbers).

Sorry if that's confusing but hope it makes sense in terms of being a look into my crazy head.

so is this better than Dinan Stage 2?

I want to know what drivetrain Miami is using o.O I would LOVE to have only 10-12% loss.

Originally Posted by K-A

From what I've "learned" in Dyno testing, RWD Auto cars generally see 15-20% drivetrain/etc. loss by the time it gets to the rear wheels. 10-12% is very efficient (not sure if that's even possible on an Auto?).

There's a dyno sheet I recently saw that said a "general rule is to divide by .xx(number). When I did that, it came out to roughly 20% drivetrain loss.

Also, if you look at the 535i's consensus trap speed in the 1/4 mile, being around 100 MPH (give or take depending on various tests), and weighing at about 4,000 lbs, it shows that it should pin it right at around 340 HP.

A good basis I like to use is a car I used to be involved with in terms of HP/Track times, which is the SN-99 Mustang GT. It was a very pure basis of how RWHP and track times equate.

For example: The 5 Speed Manual 2004 GT made 225 RWHP on the money, which would put it at 260 HP on the money. The Auto version of the same car sucked out an additional 10-15 RWHP, putting them generally at around 210 RWHP. Those cars weighed at around 3200-3300 lbs.

The Manual GT did exactly a 14 Second 1/4 at 100 MPH, those two numbers perfectly aligning with each other as a good power/weight ratio VS track time/MPH ratio (same exact numbers the 535i generally does).

So, if you have a 3200 lb GT making 225 at the wheels with only little drivetrain loss due to being a Manual and doing a 100 MPH trap speed, and then add 700-800 lbs to it (i.e now making it a 535i) then you'd have your trap speed dropped to 92-93 MPH (1 MPH for ever 100 lbs). Therefore, in order for the 535i to recapture that 100 MPH trap speed AND taking into consideration it's an Auto tranny which means it has even more drivetrain loss, you'd need at least 80 more HP, putting it at 340 crank HP (since the GT has 260 crank HP and does the exact same numbers).

Sorry if that's confusing but hope it makes sense in terms of being a look into my crazy head.

Wow!! That's some hardcore rain man math.. Sorry but our cars are not pushing 340 at the crank.

Originally Posted by RambleJ

Wow!! That's some hardcore rain man math.. Sorry but our cars are not pushing 340 at the crank.

OK Mr. Guru, what then do our cars put out?

A dyno of a 535i put 277 RWHP and 283 RWTQ to the wheels, straight from the showroom floor (you'll see more RWHP add up as the motor breaks in).

You'd be a one of a kind to have less than 15% drivetrain loss in an automatic, more likely 18-20%.

Also, a 4,000 lb car won't be trapping at 100 MPH with only 300 HP at the crank. Look at statistics of other cars with an *actual* 300 HP, in order to trap that high they need to weight considerably less than 4,000 lbs.

Originally Posted by RambleJ

Wow!! That's some hardcore rain man math.. Sorry but our cars are not pushing 340 at the crank.

Rain man was right on. He was very good at math. So basically, by saying it is rain man math, you agree.

But based in your second sentence, I think you meant to say that it was Duh-bya math.

At any rate, K-A is probably right, but perhaps a bit high if you consider the 5er has an 8 speed gearbox. What matters is the total area under the HP curve from start to finish (I'm trying not to use math here). With the 8 speed gearbox, you stay at the top of the curve a bit more so you end up with more total under-the-curve area by the end of the run compared to say, the GT. So there is *some* benefit to the 8 speed gearbox (maybe it's 10-15 HP benefit or something; to know would require using math and I'm many years removed from that ).

But even if you assume a super efficient 15% drive train loss, then 277 RWHP puts it over the 300 @crank HP claimed by BMW (about 326 HP, to be more specific, which would probably be enough to get the vehicle to 100 trap with the 8 speed gearbox).

-Corey

Originally Posted by RambleJ

Wow!! That's some hardcore rain man math.. Sorry but our cars are not pushing 340 at the crank.

It should be approx 330hp but 340 is not out of reach for a broken in motor. A fair parasitic loss number should be 16-18%.

So we see one or 2 dynos @260/270 and now its set in stone? Come on I know you guys have seen some high reading dynos not to mention inaccurate correction factors to show some high readings.. What do you say about those stock dynos that are in the 240s?

Plus cordoor is correct that you have to take into account our 8 speed tranny. There are many ways to push a car down the track and having proper gearing helps quite a bit

The link below calulates 4000lbs will need 313hp to attain 100mph in a 1/4 mile. Before anyone poo-poos the calculator, trust me, I don't believe in the accuracy of the dyno results either.

¼ Mile Elapsed Time and MPH Calculator

Originally Posted by dunderhi

The link below calulates 4000lbs will need 313hp to attain 100mph in a 1/4 mile. Before anyone poo-poos the calculator, trust me, I don't believe in the accuracy of the dyno results either.

¼ Mile Elapsed Time and MPH Calculator

Originally Posted by dunderhi

The link below calulates 4000lbs will need 313hp to attain 100mph in a 1/4 mile

Ok, my OCD just kicked in.

The 535i (RWD) is 4090 pounds according to BMW's website. That calculator says 320 HP is needed to reach 100 MPH at that weight (319 HP doesn't quite get you to 100, 320 gets you a bit over).

But I don't know how that calculator could be accurate.

HP is just a calculated value. It is calculated by multiplying the torque by the RPM and then applying some other adjusting number that pulls it into the range its in (I don't remember what that is).

So if you are looking at a graph of HP over RPM's, what matters in terms of power to the pavement is the area under the curve. And as everyone has noticed, there is more area under the curve on the right side of the curve (duh). So the goal is to get to that right side of the curve as quickly as possible and then to stay there as long as possible.

Gearing is critically important to this. With an 8 speed tranny, you can stay near the right side of the curve longer because when you shift from say, 1st to 2nd, the RPM's drop, but they don't drop as much in an 8 speed tranny as they would in a 6 speed tranny. You get to stay more towards the right side of the curve and so you put more power to the pavement (more area under the curve there).

So gearing matters. I don't see a way to input gearing on that calculator. But not only that, they are only asking for peak HP, so I can't see how they can calculate how much power you put to the pavement and consequently, how quickly you get to 1/4 mile.

-Corey

Generally these calculators use measured data from thousands of data points and then apply a curve fit. As I said, I don't believe in dyno results either, or at least not rolling dynos.

BTW, having a sufficient number of gears is good, but you are applying zero power while shifting, so having more gears isn't always better.

Originally Posted by cordoor

Rain man was right on. He was very good at math. So basically, by saying it is rain man math, you agree.

But based in your second sentence, I think you meant to say that it was Duh-bya math.

At any rate, K-A is probably right, but perhaps a bit high if you consider the 5er has an 8 speed gearbox. What matters is the total area under the HP curve from start to finish (I'm trying not to use math here). With the 8 speed gearbox, you stay at the top of the curve a bit more so you end up with more total under-the-curve area by the end of the run compared to say, the GT. So there is *some* benefit to the 8 speed gearbox (maybe it's 10-15 HP benefit or something; to know would require using math and I'm many years removed from that ).

But even if you assume a super efficient 15% drive train loss, then 277 RWHP puts it over the 300 @crank HP claimed by BMW (about 326 HP, to be more specific, which would probably be enough to get the vehicle to 100 trap with the 8 speed gearbox).

-Corey

Originally Posted by Emilner

It should be approx 330hp but 340 is not out of reach for a broken in motor. A fair parasitic loss number should be 16-18%.

Agreed.

Gearing is a good point to bring up, but still.

Using this example again, as I find this particular car a very accurate and solid basis for HP/Weight=Trap Speed.. the '03 Mustang GT with MANUAL (I'd assume the extra lack of drivetrain loss there could possibly equal out missing out on a few gears, who knows, but for the sake of argument....) has 260 HP on the nose (crank), and traps 100 (average). The 535i traps 100 MPH (average, I've seen some as high as 102 and some as in the high 90's, but with more broken in motors, I wouldn't be surprised if low-100's becomes more common), and weighs a good 800 lbs more. So, using the 100 lbs = 10 HP rule, we're looking at around 340 HP.

Considering gearing, and efficiency, I'd guess the N55 is putting 325-340 at the crank (a fair guesstimate).

Dyno's will range everywhere, but what's important is trap speed when trying to determine genuine power rate, IMO. So some N55's will dyno less, some more (and especially more when broken in some).

Remember, some guys with N55 3-Series' have apparently dyno'd in the 290's, stock.