1.3 Motronic Up-Grade & 2.7i How To

[E30QC]

so, can i buy a chip destined for a 2.5 and run it>? or it plays to greatly with the mix?

[eta]

Ignition timing and WOT fueling would be wrong.

[E30QC]

so, how does the 2.7 bottome end play with these settings? i mean, i use a 2.5 ecu anyways. no?- yes. right? no? yes! no?
i think i might be confused.. lol, what options does an I not have that the IS does.. the power ratings are the same?

[e30pwr]

alright are you talking about using the 2.7 bottom end with the 2.5 head? and if so yes you must use a chip that is designed for the 173 ecu and 1.1/1.3 motronic harness and wiring you have installed.

[ck_taft325is]

alright are you talking about using the 2.7 bottom end with the 2.5 head? and if so yes you must use a chip that is designed for the 173 ecu and 1.1/1.3 motronic harness and wiring you have installed.

This.

It's really about how far you take your 2.7i. If done correctly and you use the 885 head with intake, TPS, TB, wire harness etc, etc... on the ETA 2.7L block and internals, you would inevitably have to replace the ECU with one from an "i". So the chip you would use would be a 2.5 "i" (or 173 ECU) Chip.

Then boost it.

[e30pwr]

taft - that is my plan of action, lol

[E30QC]

yeah, i thought this was the 2.5 head on a 2.7 block..
anyways, so what does the chip do? i know it raises the rev. limiter, but apart from that it won't play too greatly with advance and so on..

[kenika65]

^It turns it in to a whole new monster ;)

[lateracer]

Does anybody have the details of converting a 87 325e round plug into a 88 325i wiring harness? This is the only part holding up my 2.7i upgrade

It should plug right in and work, but you are going to want to run the 88 harness for best results

Are the specific differences between these two harnesses really big, or is it worthwhile to modify the e harness if an i harness is difficult to source?

[kenika65]

e harness is trash period. :)

The e harness runs flywheel sensors and the i harness runs front crank sensor, no way to rig it....

[lateracer]

e harness is trash period. :)

The e harness runs flywheel sensors and the i harness runs front crank sensor, no way to rig it....

Hah! Alright, trash it is.

So I'll need the CPS and timing wheel for the front. Other than that, are there any other sensors that need to be swapped out?

[mph10909]

Hey I'm new here. I just finished up the swap and when I went to turn the key nothing happened. Any clue what I may have done wrong everything is hooked up right. Im lost thank you.

[Paukert11]

what did you do for the starter. I am a little lost on that part lol

[dougs87325is]

One more time, haven't seen a direct answer to this really. My 87 325is car and head swapped on a 2.7 eta block will run okay? I have the chance and parts to do this and want to turbo later on, drive for a year N/A, would it be okay, computer etc...

[EtaSport]

That question has been documented all over the Internet and forums, you just need to search. Yes you can put an I head on an e block, yes it will run okay, yes you will have stupid low compression which is okay I guess if you plan to turbo, and yes you will have an unmatched piston/combustion chamber design.