So If I Have A Full Super ETA Engine...

[Ben Carufel]

Josh is right, you need the intake manifold and throttle body as well.

The super eta, as already mentioned, already comes with an "i" head. It simply uses an eta cam with single valve springs. You need to pick up an "i" cam and dual valve springs and have the additional oil journals drilled.

Summary to convert super eta into 2.7liter "i" motor:
-"i" cam and dual valve springs with additional oil journals drilled
-"i" intake manifold and throttle body
-"i" center section (dual pipe after cats) and muffler (the exhaust manifolds are the same)
-"i" 173 ecu and chip

With the switch to the 173 ecu, I'm not sure what goes on with the fuel injectors. I know "i" injectors and "eta" injectors were different. (low impedance vs. high impedance.)

So, couldn't I just use an "i" head, since that would already have the necessary oil journal holes?

[Jand3rson]

So, couldn't I just use an "i" head, since that would already have the necessary oil journal holes?

Yes, you could. But the question you asked was "since I already have a full super eta engine", we assumed you meant you had a super-eta head as well.

[Ben Carufel]

Yes, you could. But the question you asked was "since I already have a full super eta engine", we assumed you meant you had a super-eta head as well.

I do. But why the hell would I have that head drilled when an "i" head can be had for $150...?

[Jand3rson]

I do. But why the hell would I have that head drilled when an "i" head can be had for $150...?

Because again, our answers were based on the question you asked, that question being, "since I already have a full super eta engine".

If you can get a 325i head on the cheap, then you're right, why the hell would you have the head you already have drilled? But again, that's not what you asked.

[nando]

I do. But why the hell would I have that head drilled when an "i" head can be had for $150...?

because you would have a fully rebuilt, brand new head. if your plan is to put together a stroker motor without doing any machine work (just gaskets and seals), then yes you could just get a used i head.

[SpecM]

-The ENTIRE exhaust system is the same as a 325i's.
-'88 s-etas has Motronic 1.1. The injectors can be swaped w/o the DME, you just need the chip to raise your redline.

-EDIT: I used to own a s-eta that I was modding until I wrecked it. I left the head alone and used a 325i TB, IM, and injectors. I replaced the stock '88 chip with a '88 b25i one, but had to be careful to shift below 6k. The PO had put a 4.10 LSD out back and that baby would ROLL. I should have went ahead and rebuilt the head with a b25i cam and 2x VS but I was lazy. I'd say she still made 150 hp. A FULL 2.7i with 19# injectors and an m30 afm should make 180 hp, according to Metric Mechanic.

[pdx 528e]

-The ENTIRE exhaust system is the same as a 325i's.
-'88 s-etas has Motronic 1.1. The injectors can be swaped w/o the DME, you just need the chip to raise your redline.

-EDIT: I used to own a s-eta that I was modding until I wrecked it. I left the head alone and used a 325i TB, IM, and injectors. I replaced the stock '88 chip with a '88 b25i one, but had to be careful to shift below 6k. The PO had put a 4.10 LSD out back and that baby would ROLL. I should have went ahead and rebuilt the head with a b25i cam and 2x VS but I was lazy. I'd say she still made 150 hp. A FULL 2.7i with 19# injectors and an m30 afm should make 180 hp, according to Metric Mechanic.

I'm building an M20 and was going to break the engine in on the Seta 174 ECU before installing a 325i ECU since the 174 was free with the harness I got. So all I have to do is just throw in a chip from a M1.3 ECU and it will be good to go? I ask because Ive heard the stories about how the 173 and 174 have a bad idle chip or something. I assume this problem is external to the EPROM with fuel maps and therefore still a potential issue down the road.

Not even sure what chassis this motor will go in, my 528e is damaged and I'm looking for an E30 shell.

[C ///M]

I do. But why the hell would I have that head drilled when an "i" head can be had for $150...?

Back when I was going to throw an "i" cam in the eta head, I got a quote to drill the additional oil journals. If you go to any competent machine shop, show them the cam you're going to use, they'll drill the journals for uber cheap.

Drilled journals = $30 at a high-end, overpriced place. Literally, it takes no time at all.

"i" head = $150

But if you're lazy and can get a complete "i" head for $150 that doesn't need to be rebuilt, I say go for it.