325i conversion to 330i

gunnerxq · 06-05-2011, 02:13 AM

Quote:

Originally Posted by e90pilot

Then why do the short blocks have the same part number? Where'd you get your info?

So whose right?

plokij · 06-05-2011, 02:49 AM

Quote:

Originally Posted by e90pilot

Then why do the short blocks have the same part number? Where'd you get your info?

First, I'm not saying you guys can't get meaningful gains using this method, but....

the N52B25 has:
Stroke: 78.8 mm
Bore: 82 mm

the N52B30 has:
Stroke: 88 mm
Bore: 85 mm

I'm saying that these engines are different

The vacuum system I posted earlier is very interesting because it appears to suck out back-pressure... and the part is fairly inexpensive.

Also, I wonder if buying the 330 ECU is easier than flashing. hmmmm.

plokij · 06-05-2011, 02:50 AM

Oh, and here's my "source"

http://www.bmwheaven.com/database/engine.php?type=N52

e90pilot · 06-05-2011, 04:29 AM

Well theres your answer there. The US spec 325i doesn't have an N52B25 it has an N52B30. They are both 3.0L. The 325 and 330 are the same in the with the exception of the intake manifold, programming and exhaust (resonator and muffler only, headers are the same).

Patsfan123 · 06-05-2011, 01:47 PM

Quote:

Originally Posted by e90pilot

Has anyone tried this with a '28 yet? I know the '25 works but it can be That much different from a '28.

Once I source a used manifold and DISA motors, I am doing this to my 328

plokij · 06-05-2011, 02:32 PM

Quote:

Originally Posted by e90pilot

Well theres your answer there. The US spec 325i doesn't have an N52B25 it has an N52B30. They are both 3.0L. The 325 and 330 are the same in the with the exception of the intake manifold, programming and exhaust (resonator and muffler only, headers are the same).

ahh, i see. so only the z4 kept the naming scheme true to the engine size while the 3 series confused everyone. maybe should have been 330i and 330iS...

anyway, the performance exhaust (both resonator & muffler) is the same part across both the 325 and 330. the 330's vacuum control for the stock exhaust flap then becomes an unused part if the perf. ex. is fitted.

so for a 328, if one installs the manifold, perf. exhaust, optionally the perf. intake... then all that's left is the effectiveness of the ECU firmware to gain around 30hp... right?

i guess the only drawback would be the total cost of this ranging from 2500 to 5000 bucks depending on the exhaust system used and whether or not the perf. intake is added.

i say it's well worth it!

06-05-2011, 02:50 AM	#25
plokij Lieutenant 39 Rep 505 Posts Drives: Nothing Join Date: May 2011 Location: SoCal iTrader: (1)	Oh, and here's my "source" http://www.bmwheaven.com/database/engine.php?type=N52
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06-05-2011, 04:29 AM	#26
e90pilot Freight Dawg 105 Rep 2,103 Posts Drives: E90 325i Join Date: Jul 2005 Location: Oakland, CA iTrader: (3)	Well theres your answer there. The US spec 325i doesn't have an N52B25 it has an N52B30. They are both 3.0L. The 325 and 330 are the same in the with the exception of the intake manifold, programming and exhaust (resonator and muffler only, headers are the same). __________________ --Marcelo '06 Arctic Metallic 325i \| Sport Package \| 6MT \| Dinan Stage III suspension \| Dinan exhaust \| 330i manifold swap! Click here! \| Active Autowerke tune \| 135i Brake Calipers \| Deiselboost caliper brackets \| E46 M3 front rotors
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