[heath55]

hey,

Just wondering is it possible to replace an N52B25 engine that originally came with a silver top engine with the one that comes with a black top? I think the back tops started in NOV 08' as they had the revised heads...just wondering if it is an issue at all? Or can you just bolt the newer version in without a problem?

Cheers

[David0ff]

straight swap

[hassmaschine]

sure, but unless yours is completely dead, there's no real point - they're almost exactly the same.

[playground]

The black top is not as a good as the older top to be honest, the valve cover gasket and the plastic valve cover tends to leak a lot.

[hassmaschine]

the plastic valve covers also like to crack and the PCV system isn't serviceable.

earlier motors can have lifter noise issues although most of those should have been addressed by now.

[SDemetris]

Different ecu. I believe the silver top ones are older so some might have sured the older dme... everything else is a straight swap tho

[hassmaschine]

yes they have MSV70 instead of MSV80. The upshot is you can hack MSV70 a lot easier.

[Pete.J]

Sorry to hijack your thread heath55, but I have the same question, so instead of creating a new thread I'll post here if you don't mind..

I bought a 6MT 325i with N52B25 a week ago, the car has gone through a litre of oil in one week (about 700km/435 miles), engine has 88,000 miles on it. I got the car inspected at a BMW specialist after I found out about its oil consumption issue and on initial inspection they suspected it's either worn out valve stem guides or worn out pistons. i.e. it's either a button end (block) or a top end (head) problem.

The BMW specialist suggested that replacing the engine with a lower kilometer healthier engine is the cheapest and safest bet to solve the oil consumption issue.. rather than disassembling my current engine into pieces and trying to figure out the cause of the issue and replacing individual components

I went back to the dealer and got him to contact the BMW specialist and I reached an agreement with the dealer to replace the engine under the dealer warranty since I've only had the car for four days.

The dealer called a few wreckers and we found a N52B25 engine with black engine cover done 67,000km (41,600 miles) for $2,700. The problem is my car has the silver top engine in it atm.

Are both engines fully 100% compatible with each other?

Would the black top engine work fine with the ECU from the silver top engine (current ECU in car atm)? I read above that the ECU is different for the two engines, and I also know that the ECU on these cars is VIN locked i.e. I can't take the ECU from the donor car.. If the ECU wasn't VIN locked I would have swapped it to N52B30 and got myself a 330i.

N.B. 330i only come in 6AT in Australia, so if I really wanted a manual E9X my options were 6MT 325i with N52B25 or a 6MT 335i with N54B30. 335i is out of my budget so I chose the N52B25 powered 325i in 6MT

Lastly, is the black top N52 engine superior to silver top in anyway? I know that it has the revised head and I also heard that the black top engine is a slightly stronger engine because it has slightly thicker connecting rods and overall slightly better internals. I might be slapping a supercharger on it in a year's time or something, ^ so if what I wrote above is correct in regards to the strength differences of both engines may be I should just get the black top engine if it'll work with my ECU

[Yury]

Originally Posted by pitos_7

Sorry to hijack your thread heath55, but I have the same question, so instead of creating a new thread I'll post here if you don't mind..

I bought a 6MT 325i with N52B25 a week ago, the car has gone through a litre of oil in one week (about 700km/435 miles), engine has 88,000 miles on it. I got the car inspected at a BMW specialist after I found out about its oil consumption issue and on initial inspection they suspected it's either worn out valve stem guides or worn out pistons. i.e. it's either a button end (block) or a top end (head) problem.

The BMW specialist suggested that replacing the engine with a lower kilometer healthier engine is the cheapest and safest bet to solve the oil consumption issue.. rather than disassembling my current engine into pieces and trying to figure out the cause of the issue and replacing individual components

I went back to the dealer and got him to contact the BMW specialist and I reached an agreement with the dealer to replace the engine under the dealer warranty since I've only had the car for four days.

The dealer called a few wreckers and we found a N52B25 engine with black engine cover done 67,000km (41,600 miles) for $2,700. The problem is my car has the silver top engine in it atm.

Are both engines fully 100% compatible with each other?

Would the black top engine work fine with the ECU from the silver top engine (current ECU in car atm)? I read above that the ECU is different for the two engines, and I also know that the ECU on these cars is VIN locked i.e. I can't take the ECU from the donor car.. If the ECU wasn't VIN locked I would have swapped it to N52B30 and got myself a 330i.

N.B. 330i only come in 6AT in Australia, so if I really wanted a manual E9X my options were 6MT 325i with N52B25 or a 6MT 335i with N54B30. 335i is out of my budget so I chose the N52B25 powered 325i in 6MT

Lastly, is the black top N52 engine superior to silver top in anyway? I know that it has the revised head and I also heard that the black top engine is a slightly stronger engine because it has slightly thicker connecting rods and overall slightly better internals. I might be slapping a supercharger on it in a year's time or something, ^ so if what I wrote above is correct in regards to the strength differences of both engines may be I should just get the black top engine if it'll work with my ECU

1. If you want to solve the problem for good, swap for N52B30, other wise there is no guarantee that donor N52B25 engine wont have the same issues.
2. Silver engine has a different configuration of the oil separator valve, it stands seprately, while on the LCI engine its built-in in to the valve cover. So, the connecting piping is slightly different.
3. DME MSV80 on EUR cars has no issue to be hacked, I flashed mine with 330i config when I did my swap to N52B30. Running over a year no trouble.
So if that is the case also for AUS cars then you keep your DME. MSV80 provides more power compare to old MSV70. 272 vs. 258 hp.
4. I do not see the problem to take N52B30 engine from AT car and put to your car with MT. AT and MT engines have different flywheels but mechanically it does not restrict you from useing AT engine for your swap. That if you plan to keep your MT setup.
5. The oil consumption on N52B25 in general are ususally caused by three things - valve guides (they loose elasticity over time) and/or worn piston rings and/or clogged oil separator valve. Fixing those issues will cost very closely to the price of used N52B30.

[mike-y]

Originally Posted by Yury

1. If you want to solve the problem for good, swap for N52B30, other wise there is no guarantee that donor N52B25 engine wont have the same issues.

how would he know for sure that a used N52B30 wouldn't also have the same issue? unless he's getting a new engine, there aren't any guarantees. Though I do understand the logic that if he's going to swap, just get an N52B30, and "upgrade" at the same time.

3. DME MSV80 on EUR cars has no issue to be hacked, I flashed mine with 330i config when I did my swap to N52B30. Running over a year no trouble.
So if that is the case also for AUS cars then you keep your DME. MSV80 provides more power compare to old MSV70. 272 vs. 258 hp.

The only issue with the DME is that they are VIN locked to one car. so swapping in a different DME won't work unless it's coded to your car's VIN. As long as someone can do that, he is fine. But he can also just use the old DME without issue (and reprogram it, if he has to). if he keeps the old DME, he *may* have to swap over the old engine wiring harness also, but I am not sure about that.

the 272 hp 330i had the N53, not N52 engine. So it's not the DME that makes the difference. The N53 has higher compression, Direct injection, and does not have valvetronic. it's probably more closely related to the N54 than it is to the N52

4. I do not see the problem to take N52B30 engine from AT car and put to your car with MT. AT and MT engines have different flywheels but mechanically it does not restrict you from useing AT engine for your swap. That if you plan to keep your MT setup.

I agree

5. The oil consumption on N52B25 in general are ususally caused by three things - valve guides (they loose elasticity over time) and/or worn piston rings and/or clogged oil separator valve. Fixing those issues will cost very closely to the price of used N52B30.

probably true as well. although if you can verify it is only the valve guides, rebuilding the cylinder head may come out to less money.

[hassmaschine]

yeah, the DME has nothing to do with how much power it makes. They're almost exactly the same anyway. The main difference is MSV80 uses a tri-core CPU and MSV70 uses a Motorola PPC CPU.

MSV80 cannot be cloned. you cannot copy your ISN from one DME to another. you also cannot use BDM, only OBD to tune it. There is also no way to disassemble the program code. When I say hack, I mean a lot more than flashing a tune over OBD.

[lichtgelb]

Originally Posted by pitos_7

Sorry to hijack your thread heath55, but I have the same question, so instead of creating a new thread I'll post here if you don't mind..

I bought a 6MT 325i with N52B25 a week ago, the car has gone through a litre of oil in one week (about 700km/435 miles), engine has 88,000 miles on it. I got the car inspected at a BMW specialist after I found out about its oil consumption issue and on initial inspection they suspected it's either worn out valve stem guides or worn out pistons. i.e. it's either a button end (block) or a top end (head) problem.

The BMW specialist suggested that replacing the engine with a lower kilometer healthier engine is the cheapest and safest bet to solve the oil consumption issue.. rather than disassembling my current engine into pieces and trying to figure out the cause of the issue and replacing individual components

I went back to the dealer and got him to contact the BMW specialist and I reached an agreement with the dealer to replace the engine under the dealer warranty since I've only had the car for four days.

The dealer called a few wreckers and we found a N52B25 engine with black engine cover done 67,000km (41,600 miles) for $2,700. The problem is my car has the silver top engine in it atm.

Are both engines fully 100% compatible with each other?

Would the black top engine work fine with the ECU from the silver top engine (current ECU in car atm)? I read above that the ECU is different for the two engines, and I also know that the ECU on these cars is VIN locked i.e. I can't take the ECU from the donor car.. If the ECU wasn't VIN locked I would have swapped it to N52B30 and got myself a 330i.

N.B. 330i only come in 6AT in Australia, so if I really wanted a manual E9X my options were 6MT 325i with N52B25 or a 6MT 335i with N54B30. 335i is out of my budget so I chose the N52B25 powered 325i in 6MT

Lastly, is the black top N52 engine superior to silver top in anyway? I know that it has the revised head and I also heard that the black top engine is a slightly stronger engine because it has slightly thicker connecting rods and overall slightly better internals. I might be slapping a supercharger on it in a year's time or something, ^ so if what I wrote above is correct in regards to the strength differences of both engines may be I should just get the black top engine if it'll work with my ECU

Check the CCV before swapping out engines. If the diaphragm is cracked you can get full manifold vacuum at idle on the crankcase and pull oil into the intake. Does it smoke at idle? A CCV replacement is around $270 USD for parts...that's a lot cheaper than a used engine with unknown problems of its own.

[Yury]

To mike-y

N52B30 has a different piston scirt design and very rarely has "oil" issue. I am telling that because we here have tons of n52b25, therefore have some statistics, unlike USA where there is zero of 2,5 liter n52's, which have the oil issue simply due design flaw.

In US cars DME is locked and you cant just load 330i setup in, thats why you have tons of AA and other companies who modify the original setup instead of just simply flashing it with 330i when you do 328i 3 stage intake. Here it is not the problem, we can use DME from other cars and reprogramm for required vin. By the way engine wire harness is the same on n52b25 and n52b30, checked myself when i did my swap, I used my harness from n52b25 for 3 liter engine.

Here you are mistaken, bmw had 272 hp n53 as well as n52. From my info n52b30 272 hp was on LCI 330i coupe. click simple search.

We just live in the different worlds

[hassmaschine]

even if there was a 272hp N52, it's not because it had a different DME.

our DMEs are not locked? yours still has an ISN, and on MSV8X, you can't copy it. Even if you changed the VIN somehow it would not start..

[Yury]

Originally Posted by hassmaschine

even if there was a 272hp N52, it's not because it had a different DME.

our DMEs are not locked? yours still has an ISN, and on MSV8X, you can't copy it. Even if you changed the VIN somehow it would not start..

all n52b30 with MSV70 had 258 hp at most, the raise of hp came with MSV80, strange isn't it. What, if not DME regulates the power output? Why AA and Evolve reprogramm DME and the engine give more power and torque?

Ours not, thats what my bmw electric told me.

[rjahl]

Originally Posted by Yury

all n52b30 with MSV70 had 258 hp at most, the raise of hp came with MSV80, strange isn't it. What, if not DME regulates the power output? Why AA and Evolve reprogramm DME and the engine give more power and torque?

Ours not, thats what my bmw electric told me.

Ok does anyone have documents from BMW that indicates 272 hp? Don't trust the figures posted at BMW Archive, they are not 100% correct.

[hassmaschine]

Originally Posted by Yury

all n52b30 with MSV70 had 258 hp at most, the raise of hp came with MSV80, strange isn't it. What, if not DME regulates the power output? Why AA and Evolve reprogramm DME and the engine give more power and torque?

Ours not, thats what my bmw electric told me.

It has more power presumably because of a different tune & maybe hardware.

The tuners can make more power because BMW has to make the cars work for many different environments with many different grades of fuel. Also, they have to pass emissions and they get dinged for fuel economy. It's not like they get tuned to the ragged edge of performance from the factory, nobody does that.

a physical computer can't make more power than another one. The hardware is almost exactly the same. The only difference could be the tune, but they have the same sets of maps - the vanos, ignition, fuel, valvetronic, etc. can all be tuned the same in MSV70 as in MSV80.

Basically, no, just no. Whoever told you the DME makes the difference is flat wrong. the N53 made 272hp, yes, but it's a slightly different engine.

[Yury]

Originally Posted by hassmaschine

It has more power presumably because of a different tune & maybe hardware.

The tuners can make more power because BMW has to make the cars work for many different environments with many different grades of fuel. Also, they have to pass emissions and they get dinged for fuel economy. It's not like they get tuned to the ragged edge of performance from the factory, nobody does that.

a physical computer can't make more power than another one. The hardware is almost exactly the same. The only difference could be the tune, but they have the same sets of maps - the vanos, ignition, fuel, valvetronic, etc. can all be tuned the same in MSV70 as in MSV80.

Basically, no, just no. Whoever told you the DME makes the difference is flat wrong. the N53 made 272hp, yes, but it's a slightly different engine.

Thing is I don't separate hard from soft, by saying MSV80 by default it means newer soft than in MSV70. I thought that simple logic used by everyone, I was mistaken

[hassmaschine]

Originally Posted by Yury

Thing is I don't separate hard from soft, by saying MSV80 by default it means newer soft than in MSV70. I thought that simple logic used by everyone, I was mistaken

actually the control algorithm is basically identical. So it has newer hardware (the CPU) but the software is really the same. The maps & everything are the same. There are slight variations in tunes but that's true for any DME (there are lots of different tunes for MSV80, with varying power, just like there are for MSV70).

So there are slight variations in tunes - but MSV80 isn't objectively "better" than MSV70. The reality is, all versions of MSV80/MSD80 are based on MSV70/MSS70.

Maybe it runs a few cycles per second faster, but that's not going to translate into better engine performance. Full throttle power output is actually extremely simple - even today, the full throttle fuel and ignition is basically a 2D curve.

TriCore is really just a common embedded controller that's made for cars. More than likely, it was just cheaper to mass produce them with a common CPU and port the software over from the custom Motorola hardware.

simple logic.. first you have to understand what you're talking about.

[Yury]

Originally Posted by hassmaschine

actually the control algorithm is basically identical. So it has newer hardware (the CPU) but the software is really the same. The maps & everything are the same. There are slight variations in tunes but that's true for any DME (there are lots of different tunes for MSV80, with varying power, just like there are for MSV70).

So there are slight variations in tunes - but MSV80 isn't objectively "better" than MSV70. The reality is, all versions of MSV80/MSD80 are based on MSV70/MSS70.

Maybe it runs a few cycles per second faster, but that's not going to translate into better engine performance. Full throttle power output is actually extremely simple - even today, the full throttle fuel and ignition is basically a 2D curve.

TriCore is really just a common embedded controller that's made for cars. More than likely, it was just cheaper to mass produce them with a common CPU and port the software over from the custom Motorola hardware.

simple logic.. first you have to understand what you're talking about.

That passage does not explain why same engines n52b30 with different DME has difference of 14 hp. More over tuners improve MSV70 up to 272 hp and MSV80 up to 290 hp, by just dme tune everything else stock.

[rjahl]

Originally Posted by Yury

That passage does not explain why same engines n52b30 with different DME has difference of 14 hp. More over tuners improve MSV70 up to 272 hp and MSV80 up to 290 hp, by just dme tune everything else stock.

I'd give Hass some credit on this one, He has done his homework.

If you have a BMW document that gives an N52 powered car a rating of 272HP, please share. If it exists, I would love to pull up the ODA file and look at the maps and constants.

I've already compared the X5 3.0SI DME maps against the 330I and E89 Z4 3.0 files and there is nothing in the fuel, timing, VVT values, valve lift or torque targets that would make any difference.

Having a factory 272HP N52 file would be great. I could parse that down and post the results for all to see without too much problem.

[Dan Bilzerian]

ESS recognizes that there's a 272hp X3

http://www.esstuning.com/products/N5...-Software.html