My 128i Project

[jabwind51]

Originally Posted by toto4dwin

no difference in the front. 128/125/130 intake, manifolds all the same.
The leap forward is in the rear axle drive. I had the E87 130 Differential Drive and Output Shaft in my E82 125. Guarantee improvement!
Before that I had the BMW Performance Intake & Exhaust. Improvement is only acoustically.
Now the BMW Performance Rear Wheel Brake fits!
Cheers

hmm....anyone care to elaborate more on what this actually does??

[Bimmer-Bob]

Ah, the mythical 125i/128i to 130i conversion. The white whale of these boards that drives some men mad.

[JimD]

Letting the engine turn more rpm for a given car mph will let it accelerate faster. It doesn't do anything to the engine hp or torque. It just gives the engine greater leverage on the mass of the car. M3s seem to be geared this way and it is part of their acceleration advantage.

HP in a normally aspirated engine is all in getting air/fuel in and out. That's why I looked for differences in intake, camshafts, and finally exhaust. I also checked the little rockers that are between the camshafts and the valves in the N52 since my last post but they were the same.

So it looks like the differences in the various power levels of the 3.0 L N52 (or I guess mine is maybe N51?) are intake manifold, injectors, and exhaust manifold. I also think the exhaust after the manifold is probably different but people have already been working on that part. Then if the hardware is consistent with burning more fuel, the engine management computer also has to feed the engine that fuel and hopefully do it smoothly across the rpm band.

The tuner companies in Germany undoubtedly know the hardware differences and which are most critical. They may also have the resources to change the engine management program to make it work. Somebody trying to do this in their home shop is going to have to be pretty good or they are likely to get frustrated. And it will not be cheap. Changing the exhaust manifolds may be easier relative to programming than changing the intake since there are no computer controlled valves in the exhaust.

Another common thing to do in American V8s are to polish the insides of the manifolds to enhance airflow. I presume that would potentially be of some benefit in BMWs too. The intake looks like it is plastic so it presumably is pretty smooth. The exhaust will not be plastic so it might benefit from some polishing but you probably can't get to a lot of it. $2000 for new exhaust manifolds for a N52 is pricey. You'd think that an aftermarket company would get involved but maybe the hot rod BMW market is too small.

Jim

[jabwind51]

Originally Posted by JimD

Letting the engine turn more rpm for a given car mph will let it accelerate faster. It doesn't do anything to the engine hp or torque. It just gives the engine greater leverage on the mass of the car. M3s seem to be geared this way and it is part of their acceleration advantage.

HP in a normally aspirated engine is all in getting air/fuel in and out. That's why I looked for differences in intake, camshafts, and finally exhaust. I also checked the little rockers that are between the camshafts and the valves in the N52 since my last post but they were the same.

So it looks like the differences in the various power levels of the 3.0 L N52 (or I guess mine is maybe N51?) are intake manifold, injectors, and exhaust manifold. I also think the exhaust after the manifold is probably different but people have already been working on that part. Then if the hardware is consistent with burning more fuel, the engine management computer also has to feed the engine that fuel and hopefully do it smoothly across the rpm band.

The tuner companies in Germany undoubtedly know the hardware differences and which are most critical. They may also have the resources to change the engine management program to make it work. Somebody trying to do this in their home shop is going to have to be pretty good or they are likely to get frustrated. And it will not be cheap. Changing the exhaust manifolds may be easier relative to programming than changing the intake since there are no computer controlled valves in the exhaust.

Another common thing to do in American V8s are to polish the insides of the manifolds to enhance airflow. I presume that would potentially be of some benefit in BMWs too. The intake looks like it is plastic so it presumably is pretty smooth. The exhaust will not be plastic so it might benefit from some polishing but you probably can't get to a lot of it. $2000 for new exhaust manifolds for a N52 is pricey. You'd think that an aftermarket company would get involved but maybe the hot rod BMW market is too small.

Jim

Interesting. Didn't know too much about this. Part of me still thinks though that the exhaust manifold might not be necessary for conversion since those e90 guys were about to extract 215-->260 hp by changing the intake manifold and software. I would think it's the same too for us...but only trying it would tell...And like we saw from realoem, it seems your vert already has the right IM, but needs some new injectors for the conversion.

[jksgoh]

excuse me if i am misinterpreting this, but does it not seem like the 330 and the 128 dyno results are very similar?

[pushkin]

Originally Posted by jksgoh

excuse me if i am misinterpreting this, but does it not seem like the 330 and the 128 dyno results are very similar?

How can you misinterpret... if you see that they are similar then they are similar
However they are not identical LoL

[pushkin]

Originally Posted by jabwind51

Interesting. Didn't know too much about this. Part of me still thinks though that the exhaust manifold might not be necessary for conversion since those e90 guys were about to extract 215-->260 hp by changing the intake manifold and software. I would think it's the same too for us...but only trying it would tell...And like we saw from realoem, it seems your vert already has the right IM, but needs some new injectors for the conversion.

http://www.1addicts.com/forums/showthread.php?t=209597

[jksgoh]

Originally Posted by pushkin

How can you misinterpret... if you see that they are similar then they are similar
However they are not identical LoL

hmm.. so i am confused. they seem to have very similar power and torque ratings. But the 330 is meant to be rated at about 200kw....???

[JimD]

I hadn't looked that close but I agree it is interesting that a 2006 330i would have a nearly identical measure RWHP and torque to a 2008? 128i since the ratings are 255hp versus 230hp. Neither post says miles that I noticed and I'm not even sure of the year of the 128 but it needs to be at least a couple years older. Age/miles may explain at least some of the similarity. But these results also seem to suggest a more conservative hp rating for the 128i. It's measured RWHP do not show the expected ~15% difference from flywheel to rear wheel.

I'm still not sure how much to depend on the sketches in RealOEM but the 330i exhaust manifold looks closer to the 128i sketch than it does the X5 sketch. Part numbers do not match either newer vehicle but that is not surprising.

Jim

[toto4dwin]

Originally Posted by jabwind51

hmm....anyone care to elaborate more on what this actually does??

http://auto.howstuffworks.com/differential.htm

http://auto.howstuffworks.com/gears.htm

[Evice]

Originally Posted by toto4dwin

http://auto.howstuffworks.com/differential.htm

http://auto.howstuffworks.com/gears.htm

wtf.

[jksgoh]

Originally Posted by JimD

I hadn't looked that close but I agree it is interesting that a 2006 330i would have a nearly identical measure RWHP and torque to a 2008? 128i since the ratings are 255hp versus 230hp. Neither post says miles that I noticed and I'm not even sure of the year of the 128 but it needs to be at least a couple years older. Age/miles may explain at least some of the similarity. But these results also seem to suggest a more conservative hp rating for the 128i. It's measured RWHP do not show the expected ~15% difference from flywheel to rear wheel.

I'm still not sure how much to depend on the sketches in RealOEM but the 330i exhaust manifold looks closer to the 128i sketch than it does the X5 sketch. Part numbers do not match either newer vehicle but that is not surprising.

Jim

hmm i wonder if it is just a marketing ploy by bmw to just say the 128/125 is less powerful than the other "30" engines... probably wishful thinking though methinks

[Armada]

Coming along nicely Pushkin.

[pushkin]

Haven't updated my thread in a while...

I picked up some KWs

Suspension:


After install:

[Garduna]

sweet kw
can we get a brighter pic to see more of the drop :P

[pushkin]

Yah i will post up some better pics soon...
didn't get a chance yet

[Belarus]

Congrats buddy

I hope you'll be joining us this Saturday http://www.e90post.com/forums/showthread.php?t=415535

[Yvette]

looks like you are really enjoying the car!

[kobeballer96]

Originally Posted by pushkin

The answer is simple, the sound
I do a lot of highway driving and if I deleted the muffler it would be unbearable for me to live with it everyday. Plus leaving the muffler gives the exhuast a cleaner sound.

Oh and just as a after though we didn't actually leave the axe back. we cut off the 2.5" axe back pipe and made it into a 3" right up to the muffler.

Question your first exhaust section, is that super sprint? Or stock 125i with cat deleted then painted that silverish color? Funny how your exhaust looks like the way I want to do mine but I'm reusing my stock 128i muffler and putting a ecut out right before the muffler.

[andrey_gta]

Originally Posted by kobeballer96

Question your first exhaust section, is that super sprint? Or stock 125i with cat deleted then painted that silverish color? Funny how your exhaust looks like the way I want to do mine but I'm reusing my stock 128i muffler and putting a ecut out right before the muffler.

Ask me all you want to know - I have his exhaust he has moved on to an STI

First section is not super sprint, its custom, as is the rest of the exhuast. And the silver paint i think is thermal coating.
Its is hard to tell, but i think that section is made out of some pre fabbed pipes, that have been cut up to do that 2 - 1 join

[kobeballer96]

Originally Posted by andrey_gta

Ask me all you want to know - I have his exhaust he has moved on to an STI

First section is not super sprint, its custom, as is the rest of the exhuast. And the silver paint i think is thermal coating.
Its is hard to tell, but i think that section is made out of some pre fabbed pipes, that have been cut up to do that 2 - 1 join

That's all I needed to know! Lucky you! It sounds amazing! Better then all the other ones on here IMO.

[andrey_gta]

Originally Posted by kobeballer96

That's all I needed to know! Lucky you! It sounds amazing! Better then all the other ones on here IMO.

The video of it is on a dyno, in a garage. Its not the most ideal sound chamber.

@pj.rodriguez heard it.
I think it sounds abit louder than PE, but less metalic - inline with all the 125i's with the n55 midpipe & muffler video's.
I have videos of it in a parking garage doing drive by's that I should post