2006 325i to 330i three stage intake conversion

[TonyAngel]

I'm relatively new to BMWs, just having started out a month ago when I bought my son a 2001 325i. After having spent some time with it, I had to have one myself. I decided that I wanted a 330i. As the last 3 or so weeks rolled by and I searched for an E46 330i, I discovered that the 2006 325i was upgraded to a 3.0 I-6 and had as much power as an E46 330i. The short of it is that I just bought a 2006 325i.

Now, I'm curious about this intake conversion. There are many intakes off of 330i's for sale on ebay for around $200. Does anyone know if there is any reason why this conversion can't be done relatively painlessly? It seems to be a good bang for the buck for the power it adds, considering what a quality CAI or exhaust system costs.

Another concern that I have is the software (if that's the right term) or programming. I'm wondering if I should also be looking for an ECU out of a 330i as well. How hard is it to swap an ECU in a BMW? Would getting a new ECU for a 330i remedy the software issue? I'm looking at this route because getting a custom flash is around $800 and that really digs into the "bang for the buck" aspect of the conversion.

I suppose I could also look into supercharging, but that for that much money I coulda had a 330i.

It sure would be cool to have a sleeper 325i.

Any info is appreciated.

[TonyAngel]

Well, not much info coming in, so I've been doing research on my own trying to decipher between truth and BS. What I've come up with is that the manifold of the '06 330i (and many other models) is a direct swap for an '06 325i. It appears that the main difference between the two is that the 330 manifold has twin DISA valves, which I understand, the 325 is wired for, but lacks the programming to use.

Other than bolts, gaskets and doodads, the bulk of the shopping list consists of the the manifold itself and the DISA valves. Man, are those valves expensive!! I found a guy on ebay selling a complete used manifold and it looks like the valves are there too. They may still be good or just in need of rebuilding. From what I've read, the whole job of swapping intakes is supposed to take 2.5 hours, which means that it will likely take me a day or two.

What I'd really like to hear at this point is some input on how the my car is going to run with just the intake manifold installed, with the stock programming? I'm asking because it seems that the most expensive part of the project is going to be the programming. Places like Turner want $500 for the file, plus another $200 and change for the programmer to install the software. Anyone have any thoughts on this? That is, a way of getting the 330i software for the dual DISA setup.

This may very well be the best bang for the buck mod, except for the software. In any case, if I can get some feedback on how my car will run without the software, I may just go ahead and order the manifold and related parts. My wife is leaving for a week on a business trip soon, so I'll have a few days with her out of my hair and the use of her car.

I really need to do this on the cheap. In the last month, I've bought two BMWs, one of which needed quite a bit of money to bring it to where is needs to be. The fun wad is dwindling fast.

Maybe I should think about going back to long distance shooting. $4000 rifle and ammo at $0.75 a round is starting to look cheap in comparison.

[RocketSurgeon]

Hey, I figure nobody has chimed in since so few people have actually done this. Congratulations on the e46 and e90, those are both great cars. The naturally aspirated straight 6 is the way to go. You are correct that you just need the intake manifold and software to convert the car. I researched to see if you could just flash over the 330i software yourself, but that doesn't look like an option. Swapping the manifold is pretty easy, it would be a couple hours max. There's a pretty good thread here about the swap http://www.zpost.com/forums/showthread.php?t=455180

BTW swapping out the engine computer for a used one is a really big deal, especially on the e90. On the earlier cars it was doable, but the e90 DME uses an encrypted tricore chip to store the ISN, it requires very expensive tools. Keys, instrument clusters, and DMEs are a big deal, everything else isn't bad.

I always recommend getting diagnostic software, for like $30 in hardware you can do everything the dealer can, plus you can code some really cool options. Feel free to PM, I can point you to download links for any kind of software you want.

[TonyAngel]

Rocket, THANK YOU! That's what I was looking for. Are you saying that I could flash my ecu myself?

[RocketSurgeon]

I researched, and although it is possible to write the 330i firmware to your DME, the car won't run right. Apparently BMW set some antituning protection that locks the DME against a power level change once it has been run for 10 hours. It looks like the best option is an aftermarket tune.

[TonyAngel]

Thanks for the heads up That's gonna be another $700 or so, but I'm sure that the first drive will make me forget about the money.

[TonyAngel]

Oh, I forgot to ask. How will my car run with the 330 manifold without the tuning? I suspect, the same way it does now, but don't want to assume anything. I have the manifold and DISAs on the way, but I have to take care of some stuff on the E46 before I go spending money on something like a performance tune for the E90. If it'll be ok, I'll go ahead and do the manifold swap and wait for the tune.

[RocketSurgeon]

I'm told that it will run, and the additional DISA valve will even open and close at the designated RPM. It just won't make the extra power. I don't any specifics, but it should operate like normal.

[TonyAngel]

Thanks, man. I have to get the control arms on the e46 done first, but I'm gonna throw that intake on next opportunity.