Chipping 1986 325i - can early motronic be chipped

[grimbleweed]

I have early 1986 325i - can this motronic unit be chipped - all adverts say 1988 onwards?

[pnd]

yes see zone shop these early cars benefit more from chipping than the facelift models.

[ed325i]

yes they can I had a chipped 073 ecu.

[grimbleweed]

Looked in Zone shop - all chips say >88 which I take to mean later than 1988 - mine is 1986.
HELP

Also is it difficult to install chips.

[GDBN]

If you can solder then you might be able to do it yourself as you'll be going from a 24 pin chip to 28.
You can remove your current ECU and send it in to be chipped or alternatively buy a used ECU and send that in.
Then you just swap them over when you get the new one.

G

[Andyboy]

yes see zone shop these early cars benefit more from chipping than the facelift models.

No they don't! Plastic bumper cars were all catalyst prepped and run very lean fuel/air mixtures and they need help. Early cars were not and apart from giving the timing a boost at the top end of the rev range there isn't a lot you can do with them as the mixture is pretty much spot on. This is why the old metal bumper 325i's were so much livelier that the later ones. I've had 3 or 4 or each and the early cars have a lot more bite.

[grimbleweed]

Basically not a lot to be gained then. Thanks for the comments

[only_sideways]

Hi, I have an early 320i with a bosch ecu which Im guessing cant be chipped. Is it just a straight swap with a later Motronic and which version/part number would be best for chipping? I also have an '85 M535, would this benifit from the m30 chip offered in the zone shop or are there different ECUs fitted across the E28 range also? Thanks

[dazleeds]

IF YOU LOOK CLOSELY YOU WILL SEE IT SAYS THE FOLLOWING ON ZONE SHOP sorry caps

upto 88
E30Zone Wild Chip
E30 325i >1988


after 88
E30Zone Wild Chip
E30 325i 1988 >

[only_sideways]

I was led to believe Bosch units were un-chipable

[Speedtouch]

Motronic is Bosch!! Any car with it is chippable, while the earlier Bosch L-Jetronic ones can't, because it's an analogue system as opposed to the digital Motronic.

[only_sideways]

excuse me, i was led to believe that EARLY Bosch ecus were unchipable,you're contradicting yourself, are you not??

[Speedtouch]

Early L-Jetronic ones cannot: later Motronic ones can. I am not contradicting myself in any way

[zaust]

If it has an ecu then something can be done.!. Mild to wild..

[only_sideways]

Can an L-Jetronic be replaced directly with a later Motronic?

[Ant]

nope, L jet cannot be swopped for Motronic as easily as that I'm afaraid
Jetronic can only be tweaked by using a piggyback, so as an upgrade retrofit the entire motronic from a later car and gain 3D mapped ignition @ the same time

lots of work though, MS anyone

[gooner1]

If it has an ecu then something can be done.!. Mild to wild..

Zaust are you talking about the tip you gave me a few sundays back?
havent had the chance to try it yet.Or the balls tbh.

[only_sideways]

So aside from the actual ECU, what bits do i need from a breaker?

[Speedtouch]

Believe it's the injectors, wiring loom, throttle body, sensors. The distributor is also completely different - block mounted on L-jetronic, mounted on end of camshaft for Motronic.

[only_sideways]

Cheers, thanks for the help

[pnd]

interesting comments from andyboy I agree that the early cars are quicker but from my experience they respond to chips better also. Ant any comments?

[gooner1]

PND, are you saying that you have actually had an early car chipped,if you did was that a straight chip or did you have to swap injectors,tb, etc etc?.
Knew the chrome bumbers looked better,did,nt realise they were quicker too.

[bigkev]

i was thinking of doing the same but running the spark signal through my block mounted distributor instead of the cam driven idea so this will give me infinately adjustable timing as well as the benefit of motronic injection unless i'm missing something this should work well

[zaust]

If it has an ecu then something can be done.!. Mild to wild..

Zaust are you talking about the tip you gave me a few sundays back?
havent had the chance to try it yet.Or the balls tbh.

No you can still remap on top of that....

Balls ?????

[Ant]

the early cars with the high comp engine and 073 ECU were built to perform, the post 88 were built to comply with new emissions regs, so cant really be compared.

the later cars benifit from more fuelling right thorught the rpm range, and work better as a result , with reduced consumption to boot.

the 073 has the fuel it needs as stock, but the timing is a little tame and the fuel curves do need a tweak to make the overall package gel together .

you can experiment on those with the fuel quality switch, but its @ your own risk !!

i was thinking of doing the same but running the spark signal through my block mounted distributor instead of the cam driven idea so this will give me infinately adjustable timing as well as the benefit of motronic injection unless i'm missing something this should work well

the std motronic dizzy is a "dumb" device, the advance/dwell are all handled by the ECU directly, based on load info from the TPS/AFM and RPM's , you could use the Jetronic dizzy in this fashion if you welded the internals to fix its mech advance, then swing the base timing to gain a degree or two, but that would be effective over the entire rpm range, so not advised TBH dude.

3D igniton is a major advance over the 2D mech dizzy setup, I can see where you're going on this but TBH, if thats what you want to try, slot the CPS bracket and move the base timing with that method.

HTH

[pnd]

All im saying is this ive chipped two 87 chrome bumper cars which benefitted more than the facelift car i have now which didnt show great gains with a chip. zone wild chip used in all cases. All the cars in question were in very good shape mechanically.

[Andyboy]

you could use the Jetronic dizzy in this fashion if you welded the internals to fix its mech advance, then swing the base timing to gain a degree or two, but that would be effective over the entire rpm range, so not advised TBH dude.

Or just bolt the Motronic rotor arm adaptor onto your existing cam and add a Motronic top cambelt cover and distributor cap - piece of piss. Then throw that hateful distibutor in the bin. They were shite 20 years ago - bobweights, vacuum advance/retard etc is all Hillman Minx technology. Bin it.

Use a complete loom and ECU from a plastic bumper E30 as the old type from the metal bumper cars with the two flywheel sensors is a pain in the arse - too much to go wrong. I think using the LE Jet injectors will fry a Motronic ECU - right Ant??
There are two threaded holes in the M20 block to take the alloy mount for the front TDC sensor. As long as your car has the later C101 connector (mid 85 onwards) it shouldn't be a bad job to do.

[surj]

i had a 323i bored n stroked to 2.7l but running on jetronic setup ive since replaced complete loom and everthing else to motronic seems to run betta

[Ant]

I think using the LE Jet injectors will fry a Motronic ECU - right Ant??

Damn right andy, waaaaay too much current for the driver FETs to handle.

[bigkev]

is the crank sensor on the front of mine any use looks like its only used for diagnostics and is not very well mounted to be honest
the main reason i want to keep the dizzy is for originality really so when i pop the bonnet no one knows its a 2,7 with motronic management
mines an 84 model so whats my options if i dont have the right connector

[surj]

ive got a 323i bored an s to 2.7 swopped from old running gear to motronic changed the lot i think its a better setup whats anybody else think

[bigkev]

did you use your original rods surj

[Ant]

320/323/Eta rods are all the same part number dudes.

re the '84, total rewire and new cluster required there dude, MS instead sod originality

[bigkev]

i didn't think it would be that easy,why the need for a new cluster?

[Andyboy]

Kev, my C1 2.3 ran a 2.7 using a 325i head/pistons but still with the original LE Jetronic inlet manifold, small bore throttle body and LE Jet+ distributor. It ran and drive well (superb torque) but wouldn't really rev much over 5000.
It IS possible to keep LE Jet. But the standard injectors probably won't flow enough fuel at the top end and the timing won't be right. Your best bet is to send the distributor to Aldon Enginedering (Google it) to have the advance curve modded and you could run E28 525i/528i injectors. There's nothing actually wrong with LE Jet - it's just old fashioned. You can't remap the ECU so you'd set to set it up on the dyno with an adjustable fuel pressure regulator - plus a play with the timing.