[allmotorh22]

Hello, "newb" here

Just thought I'd put in my 2 cents (and years of drag racing experience), with regard to creating power for the E90.

I just don't get why everyones so hard up on the 3-stage intake manifold... butterfly valves are nothing new to production cars and in most cases are a nuisance when it comes to making peak HP. (*good for mid range)

I just think that the 325i would be better served by bolting on a larger throttle body, as the one seen here:
http://www.dinancars.com/store/produ...cat=411&page=1

Unfortunately, I believe the biggest difference between the two engines (330vs325) may just be the cams... And the biggest tragedy with the E90 is the lack of accessibility to the computer's tuning program...

Why has no one found out how to flash the computer to get a 325i to run a turbo yet?! Ultimately what that means is that no one has the ability to drastically change the fuel maps to supply adequate fuel to the engine (even in a race environment?)...

Ah well, just had to get that out of my system, because as a new owner of a 325i, I'm utterly disappointed with the limiting factor of this car when creating power happens to be the most critical factor (tuning the computer).

cheers

[robbiec]

Please present your evidence showing that the 325 and 330 have different cams. Most of us on here have been under the impression for the past 5 years that the two engines share a common camshaft part number.

Why do you want to turbocharge your 325? BMW has done a wonderful job with the 335. Two turbos, intercooler, fuel system, hoses, brackets, etc. Show me an aftermarket turbo or supercharger kit for any car that comes in under $4k including all those goodies plus ECU tuning. Just get a 335, or better yet, a Mustang or Camaro if you need to drag race.

The throttle body in Valvetronic cars is just a failsafe in case the Valvetronic system fails. The throttle body is in WOT position all the time, except MAYBE during cold starts. The throttle body is not a restriction in this system.

As for the 3-stage manifold, from your drag racing experience you must certainly know that short runner manifolds make great high RPM power, but provide poor around town driveability. Conversely, long runner manifolds provide low RPM response, but the ram charging effects go away at high RPM. The 3-stage manifold effectively provides three runner lengths in one package by opening and closing valves in the intake plenum. The traditional 325 manifold is tuned for low-mid range efficiency, while the 330 offers a nice broad torque curve from 1,500 to 6,500 RPM.

[335imax]

Id like to hear more opinions on the Dinan High Flow Throttle Body. Anyone bought this? Tempting for me....

http://www.dinancars.com/store/produ...cat=403&page=1

[CJBimmer]

I agree with the OP 100% about the intake. I'll have to check real OEM bout the cams.

The general operating assumption has been that the one stage manifold (those equipped on the 325i and 328i) are in the 'open' position. IE, they have the same characteristics as the 3-stage would with both DISA valves open.

If thats true, then the 328i (and 325i) should be able to achieve the same hp and torque profile as the 330i for the 3rd stage of its manifold, implying we should also be able to achieve the higher peak HP that the 330i has.

Im convinced its all in the software somewhere. There has to be a simple way to fix this. I wish I had the tools and I would do it myself.

[just4kickz]

Originally Posted by 325imax

Id like to hear more opinions on the Dinan High Flow Throttle Body. Anyone bought this? Tempting for me....

http://www.dinancars.com/store/produ...cat=403&page=1

ksfrogman posted losses with his other mods... i think it was +gruppe m intake +eisenmann exhaust

it might work better if you only had dinan parts.

[mike-y]

The 330 3-stage manifold is not like the Honda H22a manifold. I am also familiar with hondas, and know about the dual stage manifolds on the the B series and H series engines. The honda manifolds switch from long to short runners to create power at different ranges of rpms.

The BMW manifold does not work the same way. the runners on the BMW manifold are static, and the DISA valves open different parts of the plenum at different rpms. The engine pulses produce reflection waves off the inside of the plenum which cause air pulses that create more power. it's more like an acoustical chamber for the air. The result is increased power at both the low and high rpms.

A throttle body isn't going to do anything for these engines. for one thing, the air still has to pass through a MAF, which is a set bore size. a bigger throttle body is still going to be restricted by the the size of the MAF. Hondas don't use a MAF, so they don't suffer from the same type of intake restrictions. Also a giant throttle body isn't going to do you any good when you can't properly match the bore to the intake plenum. The N52 uses a plastic manifold, and has very little (if any) room for a larger throttle opening.

And camshafts on the 325/328/330 are all the same. valve lift is controlled by the valvetronic system, not the camshafts.

[Wlew]

for the price... the throttle body isnt worth it. ksfrogman is the only one who has tested it and he lost power. never saw a dyno on that though so who knows. I dont think dinan would make a part that loses power... however, for 400 bucks plus a 300 deposit... its just not worth the trouble for a couple of hp, maybe. I have beat myself over this mod and have wanted to do it, but cant justify 400 bucks for unproven gains. I would love to do it though, because in theory, more air in is more power, but as everyone above has stated... the MAF controls all of that, so even if there were gains, it would be minimal, and something we would never feel.

[e90pilot]

OP, your jumping too quick to conclusions. You say the only reason we don't have an N52 turbo is the fact that no one has enough access to the ECU to tube it. Well, there are plenty of N52 tunes out there that have modified fuel mapping. In addition, modern ECUs come pretty well tuned for the factory and also work differently than with older cars. I think the reason we haven't seen any turbo application is the fact that there isn't enough demand to offset the R&D costs. Also, there is already a turbo 3 series available, so most people would buy that instead of a turbo kit for an N52. There are N52 fans here like me who want nothing to do with an N54/55.

The bottleneck in this engine is the engine itself. It was designed to get good gas mileage and be road friendly not be a high RPM screamer. BMW changed the combustion chamber design for the new 528s so that it gets 30 more ft-lbs of torque. I think the only was to get power out of the N52 is FI or go crazy with the internals.

[allmotorh22]

losing power from straight bolt-ons does not surprise me...

You could make the motor breath with all the bolt ons you want, but without the supporting fuel maps, the motor will lose power (run lean, in a turbo setup = detonation)

Why is no company competent enough to develop custom programing? (for NA setups)

I'm assuming that the current companies are simply reflashing your computers with more aggressive timing curves (telling you to run 93 octane) and not modifying the fuel maps properly.

(I'm an all-motor guy and this motor does not defy logic nor is it the exception to the rule)

This is my challange to your "tuning companies" to come out with a decent tuning program that proves me wrong.

[mike-y]

tuning is more tricky on these engines because of how the valvetronic works. current tunes from BMS, Gintani and AA alter the fuel curves. I have a dyno of the bms pbx that shows this.

Also, the throttle doesn't control the throttle body, like it does on most cars. After the car is warmed up, the throttle plate is 100% open all the time. the computer changes valve lift instead of using the throttle body to control how much air enters the engine, so it's a bit more complicated, and apparently, the code is very hard to crack on the computer.

[e90pilot]

There you go again with the assumptions. The ECU on the N52 adjusts timing in different way than you think. You can't just set a more aggressive timing profile. It has a maximum advance given ideal conditions and best fuel. Basically it's the best advance you can run even if you had the best fuel and weather conductions. Any more advance would not yeild more power. (it's 30 degrees on the M3 I think) The the computer uses it's various sensors to reduce the advance until detonation stops. Pretty much the only thing you can mess with is fuel throttle and valvetronic mapping. Some engines just don't make power unless you do some serious modding to the internals.

What exactly do you mean by "custom programming?" My car was strapped to a dyno and adjusted several times. Why don't you get a computer and OBD cable and prove yourself right. No offense, but you've kinda been talking out of your ass a little. I know you've said that you've had years of drag racing experience but most of us here need a little more than that.

[allmotorh22]

Originally Posted by e90pilot

Why don't you get a computer and OBD cable and prove yourself right. No offense, but you've kinda been talking out of your ass a little.

LOL! don't you mean wideband? no really who's talking out of their ass? you don't have to explain to me how the ecu's work to prevent detonation. And I really don't feel like i need to prove my worth to you guys.

I'm looking at it from an outsider's perspective and I'm questioning: "Why has no one made power with this motor?"

[Gavin@MMW]

Originally Posted by allmotorh22

LOL! don't you mean wideband? no really who's talking out of their ass? you don't have to explain to me how the ecu's work to prevent detonation. And I really don't feel like i need to prove my worth to you guys.

I'm looking at it from an outsider's perspective and I'm questioning: "Why has no one made power with this motor?"

First off, welcome to e90post

Now, to answer your questions..

The N52 engine is delicate to say the least, its made of an aluminum insert for the combustion chambers that is very thin. That aluminum insert is then cast into Magnesium that surrounds the insert and makes up most of the block. While this is a strong design under normal circumstances and parameters the engine was designed for, but is not suited for high HP numbers like the N54, S52, or M54 engines are. The aforementioned motors run Iron and aluminum blocks and are much stronger and able to yield more power (on the engine itself) then our lightweight magnesium engines.

Then the transmissions we run in the N52 are only rated for 332tq at the flywheel, while the N54 ZF units are built like tanks and can handle 500whp and 450wtq. again another limit to the N52 high HP hopes.

Now the main issue is the technology employed in the engine, Valvetronic mainly and Dual Vanos.

While we do have a throttle body, it is only used as a failsafe 99% of the time, like others said it is used during cold starts for vacuum and temperature regulation. But under normal conditions its wide open (in traffic, or speeding - its wide open) and what regulates the intake and throttle is actually an infinitely variable valve system that is constantly monitored by the ECU/DME to tell the Valvetronic how much air to put in which cyl and how much fuel to allow in, and how fast to get it out. This system constantly adjusts timing to the current conditions it faces (going uphill, 105° outside, 30° outside, 91octane or 87 octane..) it measures everything and reacts accordingly - but always within a pre determined range set by the factory and is coded very well and securely into many systems, so changing it is not easy.

the ECU has amazing abilities to adjust to see a mod, for instance if you add an intake and free flowing exhaust - it doesnt see the parts, it just reads more efficiently due to the parts added and adjusts fuel and timing to the improved conditions you've created. Under perfect circumstances you will see more power with added mods then stock - in perfect conditions.

Now how much power do you expect to gain from an intake and exhaust?

Better not be too much, because it just doesnt happen.

For instance, my car has everything that can be done to it, done to it including an actual Valvetronic tuning - but I still only have 210whp on a dyno dynamics. E90 328i - auto. (pre F/I)

Even with forced induction, you still wont see a huge HP motor unless someone is willing to put their car on the line and see when it pops. No one knows the breaking point of the N52 engine, and while I very well might find out coming up soon - to this day there is no number we know it can take. BMW has never released it, nor have they responded to any inquiry on the subject.

Forced induction will yield ~350hp max in these cars. and being 300lbs lighter then a 335 - it will be able to hold its own. A built n52, with full suspension and lightweight components (wheels and tires, brakes, exhaust system...) will be a very satisfying machine.

Only a little time will tell, and if a demand develops - then more focus might go to the N52. Ive seen some things around, but none have been tested or dyno'd that i know of. (cam replacements, coils, ect)

A stroker kit is also available, if someone we're to actually build up the motor and then F/I - it will either take it and be a beast, or it will explode and you will waste $30K

[e90pilot]

No, actually I don't mean wideband. You don't need one for tuning. If you need super accurate A/F readings you can drill a hole in the header and plug one in, but it's not necessary. BMWs can be reflashed via OBD port, hence the cable. You can get tuning software for cars, hence the computer.

I'm not here for some dick measuring contest. You've come here with some inaccurate information asking a question that no one cares to answer because, lets face it, there's not much demand for it. It's the slower economy version. I've heard this from 2 different BMW tuners. Not only that, the computer is already pretty optimized for the factory. Are you really going to tell us that a company the tunes F1 cars touring cars etc that they don't know how to tune a road car? Yes they put in some safety room but not that much.

[allmotorh22]

Originally Posted by e90pilot

A wideband. You don't need one for tuning. If you need super accurate A/F readings you can drill a hole in the header and plug one in, but it's not necessary.

@e90pilot, you've got to be kidding me right? (Breakthough! Well there's the entire problem right there and what I meant by custom programming/tuning)
Anyway, I'm over it.

Thank you e90posters for explaining the whole valvetronic issue. Armed with all the information you provided, I think I know how to approach getting more power out of the N52 next time I go to dyno. (Hint: its not going to involve a 3 stage manifold)

[5erman]

address your actual question on the 3 stage manifold-

First off there are no difference in camshafts or any parts for that matter between the 2 cars except simply the 3 stage intake and software tune

Now its not the 3 stage intake itself that everyone covets or that creates the power-however the 3 stage intake allows bmw to tune the software to make good power through low, medium and high rpms because it can switch paths in the 3 stage intake.

When you put a single stage intake like stock-you have to tune the software more conservatively at the various RPM points-and if you tuned your one runner for maximum power at high rpms-then you would have a very sluggish car throughout the low-mid range. If you tuned the one runner for low-mid range than you would have a poor peak output. So bmw or any builder has to compromise with a street car and make the tune more "generic" to fit all rpm ranges given there is only one intake path.

With three intake paths-it can create an aggressive tune for max power using one runner path, which wont give up anything down low-mid because it can also use an aggressive path for the low runner and mid runner.

So its not the intake itself but its what the intake allows you to do with the software and still maintain a driveable machine.

In the end the Max power output would be NO different on a 1 stage v. a 3 stage intake if you tuned the 1 stage intake for max power---however driveability would be gone as you would lose mid-low. 3 stage allows max hp as well as great low-med. Have your cake and eat it to so to say.

So that is why the 3 stage is the key-it allows more aggressive tunes throughout the rpm range as it has more itnake paths to work with. 3 high pressure pulse points to maximize hp at 3 rpm ranges covering teh entire rpm band practically