1.3 Motronic Up-Grade & 2.7i How To

[kenika65]

so i cant run the i computer on the e motor, just like plug and play? i need to get the intake, head and everything else?

I am guessing you are talking about your 87 325?

No the i computers only hook up to 1.1 and 1.3 Motronic harness's, And No you dont have to put a 2.5i head on your 2.7 bottom end. You do have to swap over 88-92 325i,is,ix

(intake manifold, throttle body, injectors, AFM(air fuel module), FPR(fuel pressure regulator 3.0bar), all pulleys(fan, water pump, crankshaft), alternator(90 amp), belts, thermostat housing, 173ecu(computer in glove box), all 1.3 Motronic wiring and sensors, coil, wires, and plugs)

And Optional but preferable (double valve springs, valve cover, exhaust manifolds, exhaust, fuel tank, fuel pump, fuel lines,flywheel (lighter), transmission (better shifter design), starter, drive shaft, differential (4.10 from a 325ix)).

*A 30amp fuse will be needed in the fuse box for the fuel pump.

*1.3 Motronic wire harness is larger then 1.0basic Motronic harness so the inlet hole on the firewall passenger side will need to be slightly enlarged.

It seems like a long list but will only take a day or three to swap parts.

Go find a $100 89 325i,is,ix and swap parts, you will love the upgrade.

[Bimmerboy91]

so i cant run the i computer on the e motor, just like plug and play? i need to get the intake, head and everything else?

[kenika65]

so is it safe to just run the computer from the i on the e engine as long as you dont over rev it?

The i computer only connects to the 1.1 and 1.3 Motronic wire harness, so you must swap all i related parts on to the eta motor for the i computer to work.

Once 1.3 Motronic is installed your red line will be higher then the eta valve springs can handle so if you plan on revving past 5300rpm i double valve springs are suggested to eliminate valve float and possible valve spring breakage.

I ran single valve spring in my 2.7i until I was ready to install the i cam, i valve springs, head gasket, and drill 3 extra oil passages in the eta head for the i cam.

So don't plan on revving past 5300rpms with single valve springs unless you want to break something.

[Bimmerboy91]

so is it safe to just run the computer from the i on the e engine as long as you dont over rev it?

[kenika65]

1.1/1.3 Motronic Up-Grade is for 1982–1988 E30 325/325e/325es

Before you read this, think of it this way your 82-87 325,e,es has the 2.7L 9.0:1 compression M20 and the 87-92 325i,is,ix have the high performance 2.5L 8.5:1 compression M20. Now if you have both an e and an i then take all of the high performance i parts off and bolt them on to the e and you will have a high performance, high torque 9.0:1 compression 2.7L M20. This is the quick way. The long way is putting on the i head which is not necessary for this quick performance upgrade.

Now if you have an i car then I am going to suggest getting any 2.7 crank and use your i rods and buy custom pistons that already have valve reliefs cut in them and at a compression of your choice.

For 87-92 325i,is,ix,ic~2.5L modelE30 You already have 1.1/1.3 Motronic all you need is 173ecu. To build a 2.7i you will need 2.7 crank, rods, pistons(eta,seta)

2.7i How To is for 1982-1992 E30

1982-1986 325,e,es
Notes For 1982-1985: Use this diagram to connect 1.1/1.3 Motronic harness to body harness. http://i73.photobucket.com/albums/i2...85318iC101.jpg

Parts Needed:
i intake manifold, i throttle body, i injectors, i AFM(air fuel module), i FPR(fuel pressure regulator 3.0bar), all i pulleys(fan, water pump, crankshaft), i belts, i thermostat housing, i 173ecu(computer in glove box), all 1.1/1.3 Motronic harness and sensors, spark plug wires

Optional Parts:
i double valve springs, i valve cover, i duel exhaust, i radiator and expansion tank, i single fuel pump fuel tank and fuel lines, i flywheel, i transmission with drive-shaft(Must use original center support bearing), i differential(4.10 from ix), i brake booster, i 90amp alternator

1987 325,e,es
Note: In 1987 some e30 are equip with 1.1 Motronic sensors and harness and have the i pulleys and thermostat housing.

Parts Needed:
i intake manifold, i throttle body, i injectors, i AFM(air fuel module), i FPR(fuel pressure regulator 3.0bar), all i pulleys(fan, water pump, crankshaft), i belts, i thermostat housing, i 173ecu(computer in glove box), all 1.1/1.3 Motronic harness and sensors, spark plug wires

Optional Parts:
i double valve springs, i valve cover, i duel exhaust, i radiator and expansion tank, i single fuel pump fuel tank and fuel lines, i flywheel, i transmission with drive-shaft(Must use original center support bearing), i differential(4.10 from ix), i brake booster, i 90amp alternator[U]

1988 super eta, seta

Parts Needed:
i intake manifold, i 173ecu(computer in glove box)

Optional Parts:
i cam, i double valve springs, i duel exhaust, i radiator and expansion tank, i single fuel pump fuel tank and fuel lines, i flywheel, i transmission with drive-shaft(Must use original center support bearing), i differential(4.10 from ix), i brake booster, i 90amp alternator[U]

Head Piston Options

eta head with eta pistons 9.0:1 compression great torque low acceleration

i head with eta pistons 8.4:1 compression good torque good acceleration, best for turbo applications and engine management

i head with seta pistons 8.5:1 compression great torque great acceleration

i head with i rods and custom pistons 10.0:1 compression better torque excellent acceleration




Notes

Note 1: Once 1.3 Moronic is swapped in you will rev past 5300rpm so you will need to install the 7000rpm i tachometer

Note 2: Double valve springs are preferred for high rev applications but you can run the stock 86 single valve springs under 5300rpms until you are ready to take the head off.

Note 3: A 30amp fuse will be needed in the fuse box for the fuel pump.

Note 4:1.3 Motronic wire harness is larger then 1.0basic Motronic harness so the inlet hole on the firewall passenger side will need to be slightly enlarged.

Note 5: None of the i parts will increase your rev limit (5300rpm) without the 173ecu 1.3 Motronic up-grade(6300rpm) and for 7000+ rev limit try out various performance chips.

Note 6: After upgrading to 1.3 Motronic you may want to move your power curve up, so try the i cam or bigger in the eta head. The eta head will need to have oil passages drilled for the 3 extra cam journals at a knowledgeable machine shop so you can put the 7 bearing i cam or bigger in the eta head.

Note 7: The 1988 325,e,es 2.7 (super eta, seta) which is the only year with 2.7 domed pistons that mate with the i head and have proper compression for NA applications.

Note 8: (e Crank, e rods, 88 super eta pistons, i head) is the most preferred and valued combination with stock bmw parts.


Note 9: The i rods are longer then the e rods and will rev better because of the rod ratio. This combination is better then the stock parts combination but consists of custom pistons.

Note 10: If you want a better rod ratio or cant find the 88 super eta pistons then go with custom non-interference pistons that will work with (e crank, i rods, i head).

Note 11: If Turbo is in mind use (e Crank, e rods, e pistons, i head).
Because the i head has domed combustion chambers unlike the eta head which has flat combustion chambers, the matching of the eta flat top piston and the domed chamber of the i head will result in lower compression (which is perfect for turbo applications). The i head will bolt right on to the stock eta bottom end with no machining needed. The only problem is rough idle and hard start, which can be fixed with advanced engine management like MS,MS2,MMS or a custom chip.

Note 12: Here is quote from Wikipedia.com supporting the 2.7i and explaining the 1.3 upgrade.

For the 1988 model year, the eta cars got a refresh from the factory. This included a newer Bosch Motronic version with adaptive idle control, a 325i head casting with the larger valves, ports, revised combustion chambers and water jacket, new pistons to fit the 2.7 L stroke with the 2.5 L head, a dual exhaust system and a 5300 RPM rev limit. Though it only made slightly more power in stock form, it could be easily boosted by bolting on a 325i head, a complete 325i intake manifold and throttle and plugging in the 325i engine control unit. Depending on which cam, chip and intake is used, the combination can make over 180 horsepower with the stock compression ratio.
In aftermarket modifications that are inspired by custom versions of Alpina and AC Schnitzer, the long-stroke eta engine block is often combined with a 325i head to a so-called 327i that combines the high low-rev torque of the eta with the top-range power of the 325i.



Links:
Old 2.7i thread with pictures

http://www.e30tech.com/forum/showthread.php?t=39960

Plug-In Programer(Engine Management)

http://millerperformancecars.com/catalogue/435.html

i head on flat top eta pistons(Dyno Results)

http://www.r3vlimited.com/board/showthread.php?t=97872

Intake Port Differences


Piston Differences

http://www.bmwccn.no/rogaland/Mahle_m20.html

For square c101 connection (Motronic harness to body harness connection)

http://i73.photobucket.com/albums/i237/mcgrath_01/85318iC101.jpg

Wikipedia

http://en.wikipedia.org/wiki/BMW_M20

Haynes Manual
E30ManualHaynescomplete.pdf (application/pdf Object)

1.1/1.3 Motronic Manual
DME_1.1_1.3.pdf (application/pdf Object)

1983-1992 Wiring Diagrams And Troubleshooting Manuals

http://shark.armchair.mb.ca/~dave/BMW/e30/

Dealer Manual

http://ee1394.com/bmw/docs/factory/repair/en/index1.htm

M3 Repair Manual

http://pagesperso-orange.fr/s14/index.htm

My 1986 325es has the stock 82-87 325,e,es (Crank, Rods, Flat Top Pistons, Port matched head, and i cam(Note 6)) with 1.3 Motronic Up-Grade.

Everything else if from an 87-92 325i,is,ix 2.5L 1.1/1.3 Motronic

(double valve springs, valve cover, duel exhaust, intake manifold, throttle body, injectors, AFM(air fuel module), FPR(fuel pressure regulator 3.0bar), all pulleys(fan, water pump, crankshaft), alternator(90 amp), belts, thermostat housing, 173ecu(computer in glove box), all 1.3 Motronic wiring and sensors, coil, wires, plugs, fuel tank, fuel pump, fuel lines,flywheel (lighter), transmission (better shifter design), starter, drive shaft, differential (4.10 from a 325ix)).



Please ask questions and leave comments! If you need to e-mail me, my address is kenika65@msn.com