I've got an N51 motor... manifold/more power options?

Brake_L8 · 10-02-2014, 10:42 AM

I've done a bit of reading and had the famous 3-stage manifold swap in mind for my 128i. Well, after re-checking the WebETK sheet, turns out my car is a March '09 build and has the N51 motor, not the N52.

My research indicates that all N51's came with the 3-stage DISA manifold, and the motor has lower compression which pulls power down a bit.

So then, it appears that Active Autowerke has a tune available, and Evolve is working on one as well (thank you, St|g for helping me with that). Is the tune worth doing?

I guess I'm curious what sort of power potential the N51 has versus the N52. Seems you N52 folks can get 'em up to about 260-270 crank hp, so I'm wondering if I can come close to that number. The car is plenty quick as it is, but more power is always more better

harryn · 10-02-2014, 10:50 AM

Hey bud, the power difference between the SULEV and non-SULEV models is barely different and were both rated at 230. The tuning potential, once better understood, is nearly identical between the N51 and N52.

Kgolf31 · 10-02-2014, 10:53 AM

Just for reference, N51 motor here with an AA Stage 2 Tune.

I'm at 218 whp @ 200 ft-lbs currently on a 93 octane tune. Once I get headers I'll most likely go to a race gas tune.

harryn · 10-02-2014, 11:05 AM

Quote:

Originally Posted by Kgolf31

Just for reference, N51 motor here with an AA Stage 2 Tune.

I'm at 218 whp @ 200 ft-lbs currently on a 93 octane tune. Once I get headers I'll most likely go to a race gas tune.

Wow!! I personally would feel better with more torque since the HP feels fine (the distance getting to 80). But I feel it could get to 80 a bit more quickly, IMO.

Kgolf31 · 10-02-2014, 11:48 AM

Quote:

Originally Posted by harryn

Wow!! I personally would feel better with more torque since the HP feels fine (the distance getting to 80). But I feel it could get to 80 a bit more quickly, IMO.

The most difference you'll notice is the low end.

Lag/shuddering down low is basically eliminated. Response from the throttle is greatly increased and the pull to 3.5k is really noticeable.

Kontra · 10-02-2014, 01:40 PM

Really interested in the AA N51 tune myself. FWIW I never noticed that throttle response delay until immediately after I installed my SSK, where I routinely experience it now.

TheSt|G · 10-02-2014, 03:29 PM

Quote:

Originally Posted by Kgolf31

Just for reference, N51 motor here with an AA Stage 2 Tune.

I'm at 218 whp @ 200 ft-lbs currently on a 93 octane tune. Once I get headers I'll most likely go to a race gas tune.

I'll be curious to see your torque post headers with 93 as a point of comparison between the N51 and N52.

harryn · 10-02-2014, 04:10 PM

Quote:

Originally Posted by Kgolf31

The most difference you'll notice is the low end.

Lag/shuddering down low is basically eliminated. Response from the throttle is greatly increased and the pull to 3.5k is really noticeable.

Wow, that's very inspiring to hear. I was thinking about that Bav Auto sprint throttle booster thingie, but as I was telling Brake_L8, I think it is more of a gimmick than anything. Plus I don't see the benefit of it without a car that is tuned properly.

I think for now, I am just going to stick with the car in stock form, take it to a couple track events until I can get a feel for the car. I usually start with suspension and brakes first, before any power gets added. It's been my belief till today. But compared to my 95 M3... the 128i does feel a bit lethargic and my M3 is mostly stock, except for the brakes, polies, and bilstein suspension with H&R springs. I never felt a need to touch the engine.

Kgolf31 · 10-03-2014, 07:08 AM

Quote:

Originally Posted by TheSt|G

I'll be curious to see your torque post headers with 93 as a point of comparison between the N51 and N52.

Me too. I'm figuring not as impressive gains but I'll be happy if I can get to 240 whp on 93. The car next year will be most likely only a track/autox car so hopefully get a tune that can self-adapt to 100 octane. I don't feel like spending $7/gal to travel to an event

Quote:

Originally Posted by harryn

Wow, that's very inspiring to hear. I was thinking about that Bav Auto sprint throttle booster thingie, but as I was telling Brake_L8, I think it is more of a gimmick than anything. Plus I don't see the benefit of it without a car that is tuned properly.

I think for now, I am just going to stick with the car in stock form, take it to a couple track events until I can get a feel for the car. I usually start with suspension and brakes first, before any power gets added. It's been my belief till today. But compared to my 95 M3... the 128i does feel a bit lethargic and my M3 is mostly stock, except for the brakes, polies, and bilstein suspension with H&R springs. I never felt a need to touch the engine.

I can tell you the car doesn't pull like a S52 in current form. It does lack high end pull. I'm also limited to running rich from stock cats and keeping the exhaust temp gas down so I'm choking some serious power.

Besides Headers, Diff and a LTW Battery I've done basically everything I can do to the car. I'm at 2981lbs too, so that helps a bit with acceleration.

chris82 · 10-03-2014, 09:47 AM

Quote:

Originally Posted by Kgolf31

Just for reference, N51 motor here with an AA Stage 2 Tune.

I'm at 218 whp @ 200 ft-lbs currently on a 93 octane tune. Once I get headers I'll most likely go to a race gas tune.

I badly need to get active to give me the same tune. Might have to purchase a simon tool right now so they can send me the file. What did you ask them to do to get the hp/tq numbers you got?

Kgolf31 · 10-03-2014, 10:00 AM

Quote:

Originally Posted by Chrisar82

I badly need to get active to give me the same tune. Might have to purchase a simon tool right now so they can send me the file. What did you ask them to do to get the hp/tq numbers you got?

Go very aggressive; I told them I need as much power as possible, lol

He gave me a base file. I dyno'ed and provided the results and he made some changes on high end valvetronic, ignition timing and wide open fuel.

Haven't dyno'ed since then...but the numbers should theoretically be a bit better. The dyno was on the first file, not the revision.

In the end the cats are the limiting factor. In a 5th gear pull they just get too hot and you need to dump fuel before you burn them up. Aftermarket cats will solve this as you don't need to worry about exhaust temp

andrey_gta · 10-03-2014, 10:31 AM

Quote:

Originally Posted by Kgolf31

In the end the cats are the limiting factor. In a 5th gear pull they just get too hot and you need to dump fuel before you burn them up. Aftermarket cats will solve this as you don't need to worry about exhaust temp

How do we know this is happening?

Kgolf31 · 10-03-2014, 12:32 PM

Quote:

Originally Posted by andrey_gta

How do we know this is happening?

Because I run stupid rich. Over 5.5k I end up running around 12:1

You need to keep the OEM cats cool. They are controlled off EGT (Exhaust Gas Temp). If you fail to meet that the engine will dump fuel to save the cats.

Until you get rid of the OEM cats you have to dump the fuel to keep the temperature low.

chris82 · 10-06-2014, 08:38 PM

Quote:

Originally Posted by Kgolf31

Because I run stupid rich. Over 5.5k I end up running around 12:1

You need to keep the OEM cats cool. They are controlled off EGT (Exhaust Gas Temp). If you fail to meet that the engine will dump fuel to save the cats.

Until you get rid of the OEM cats you have to dump the fuel to keep the temperature low.

Is it safe running like that? As in do you foresee any future problems with the tune you're running?

631twentyeighteye · 10-06-2014, 09:19 PM

Quote:

Originally Posted by Chrisar82

Is it safe running like that? As in do you foresee any future problems with the tune you're running?

Yeah running rich is fine. like kgolf said it just dumps the fuel to cool the cats down. Running lean is what can be dangerous.

Taskmaster · 10-06-2014, 09:21 PM

Headers.

MarkkyyMan · 10-07-2014, 12:43 PM

Quote:

Originally Posted by 631twentyeighteye

Yeah running rich is fine. like kgolf said it just dumps the fuel to cool the cats down. Running lean is what can be dangerous.

Running rich is better than running lean, not good to run too rich though.

631twentyeighteye · 10-07-2014, 02:18 PM

Quote:

Originally Posted by MarkkyyMan

Running rich is better than running lean, not good to run too rich though.

Agreed. When i had o2 issues my car went into open loop mode and was dumping massive amounts of fuel to ensure it wasn't running lean(like 10-15mpg rich LOL).

No harm in this though, it's designed that way to save the engine. too rich will really just kill power but typically doesn't cause any harm. unless your injectors are just pouring fuel into the cylinders in which case it can hydrolock and bend some rods.

harryn · 10-14-2014, 02:17 PM

Is there a vendor that makes decent high-flow cats, that outperform the OEM unit?

TheSt|G · 10-14-2014, 02:51 PM

Quote:

Originally Posted by harryn

Is there a vendor that makes decent high-flow cats, that outperform the OEM unit?

Theoretically AFE, but no one has actually tested them and they are suspiciously cheap.

Supersprint does as well, and they excellent as they use HKS cats, but the price is anything but cheap.

harryn · 10-14-2014, 04:01 PM

Again, please forgive my ignorance... where is the link on this forum I can go to and see what vendors support the N52N 128i? I have a 2010 E82 coupe with M-Sport package.

Taskmaster · 10-15-2014, 11:49 AM

Go it to the vendor side of the forum.

10-02-2014, 10:42 AM	#1
Brake_L8 Ambitious But Rubbish 6 Rep 95 Posts Drives: '09 128i \| '97 M3 Join Date: Dec 2013 Location: Northern VA iTrader: (0)	I've got an N51 motor... manifold/more power options? I've done a bit of reading and had the famous 3-stage manifold swap in mind for my 128i. Well, after re-checking the WebETK sheet, turns out my car is a March '09 build and has the N51 motor, not the N52. My research indicates that all N51's came with the 3-stage DISA manifold, and the motor has lower compression which pulls power down a bit. So then, it appears that Active Autowerke has a tune available, and Evolve is working on one as well (thank you, St\|g for helping me with that). Is the tune worth doing? I guess I'm curious what sort of power potential the N51 has versus the N52. Seems you N52 folks can get 'em up to about 260-270 crank hp, so I'm wondering if I can come close to that number. The car is plenty quick as it is, but more power is always more better __________________ Now: '09 128i/6 Sport/Premium/Cold Weather \| '97 M3/4/5 #404 TTD Then: '95 Miata \| '91 535i \| '96 328i \| '95 325i \| '13 Focus ST
	Appreciate 0 Tweet Quote

10-02-2014, 10:50 AM	#2
harryn New Member 3 Rep 10 Posts Drives: 128i M Sp, 95 M3, 94 M-Technic Join Date: Sep 2014 Location: Communist Republic of Maryland iTrader: (0)	Hey bud, the power difference between the SULEV and non-SULEV models is barely different and were both rated at 230. The tuning potential, once better understood, is nearly identical between the N51 and N52.
	Appreciate 0 Quote

10-02-2014, 10:53 AM	#3
Kgolf31 Brigadier General 459 Rep 4,531 Posts Drives: 2007 Z4MC, 2012 128i Join Date: Sep 2008 Location: Ohio iTrader: (4)	Just for reference, N51 motor here with an AA Stage 2 Tune. I'm at 218 whp @ 200 ft-lbs currently on a 93 octane tune. Once I get headers I'll most likely go to a race gas tune.
	Appreciate 0 Quote

10-02-2014, 01:40 PM	#6
Kontra Private 3 Rep 79 Posts Drives: N51 128i Join Date: Feb 2013 Location: New Jersey iTrader: (0)	Really interested in the AA N51 tune myself. FWIW I never noticed that throttle response delay until immediately after I installed my SSK, where I routinely experience it now.
	Appreciate 0 Quote

10-06-2014, 09:21 PM	#16
Taskmaster Banned 2465 Rep 9,004 Posts Drives: M235i 6MT / E92 328 Msport 6MT Join Date: Nov 2013 Location: Florida iTrader: (6)	Headers.
	Appreciate 0 Quote

10-14-2014, 02:17 PM	#19
harryn New Member 3 Rep 10 Posts Drives: 128i M Sp, 95 M3, 94 M-Technic Join Date: Sep 2014 Location: Communist Republic of Maryland iTrader: (0)	Is there a vendor that makes decent high-flow cats, that outperform the OEM unit?
	Appreciate 0 Quote

10-14-2014, 04:01 PM	#21
harryn New Member 3 Rep 10 Posts Drives: 128i M Sp, 95 M3, 94 M-Technic Join Date: Sep 2014 Location: Communist Republic of Maryland iTrader: (0)	Again, please forgive my ignorance... where is the link on this forum I can go to and see what vendors support the N52N 128i? I have a 2010 E82 coupe with M-Sport package.
	Appreciate 0 Quote

10-15-2014, 11:49 AM	#22
Taskmaster Banned 2465 Rep 9,004 Posts Drives: M235i 6MT / E92 328 Msport 6MT Join Date: Nov 2013 Location: Florida iTrader: (6)	Go it to the vendor side of the forum.
	Appreciate 0 Quote