Converting an older 456 to newer M-Series Motronics - Ferrari Life
 
LinkBack Thread Tools Display Modes
post #1 of 6 Old 10-25-2012, 02:42 PM Thread Starter
Owner
 
Granucci's Avatar
 
Join Date: Jan 2007
Location: far and away
Ferrari Life Posts: 6,203
Converting an older 456 to newer M-Series Motronics

Dumb question:

The older 456 GT uses a Motronic 2.7 while the M-series uses the 5.1 for an extra 6HP. I know the firing order went back to the original sequence such as the TR etc. for the 'M', and the older GT used a differnt firing order, but other than that, I believe the engines to be nearly identical [oh, yes...upgraded valve guides]. Minor difference was an change to the leveling system [2 for the M and 3 for the older] and of course the nicer changes to interior and voided reverse hood scoops and adjusting foil but that was about it.

BUT, all that said, can one 'upgrade' the motronics for the engine, only, to the newer 5.1 system and expect perhaps a better car? I would expect this not to be too costly [about < $2k, thinking]. And I am more interested in the better management than a lousy 6HP gain.

Guide to the Galaxy: Don't Panic
Rik -- LAH !


Current:
Past:
1990 Mondial T Cabriolet SN 86247 : Red/Tan
1995 456 GT 2+2 SN 99987 : Roso Metalizzato [Fer 311/C] & Tan
Granucci is offline  
Sponsored Links
Advertisement
 
post #2 of 6 Old 10-25-2012, 03:45 PM
Owner
 
Brian's Avatar
 
Join Date: Jul 2005
Location: Austin Texas
Ferrari Life Posts: 1,833
I think it will take a far bigger conversion than you are expecting. The parts bill will be far more than 2g's for used parts and in the end you will be getting rid of what we considered probably the best Motronic system ever used by Ferrari and trading it for one of the sometimes nightmareish OBD2 systems that were rushed to market to comply with some bureacrats unrestrained zealotry.
Brian is offline  
post #3 of 6 Old 10-25-2012, 04:28 PM
Owner
Elite Member
 
cribbj's Avatar
 
Join Date: Apr 2010
Location: Houston
Ferrari Life Posts: 2,206
+1 to Brian's remarks.

In other hotrodding circles, much of the talk has been about how to retrofit OBDI ECU's to OBDII cars because the older ECU's are more tolerant and don't have such tight operating "windows" for their sensors. In addition, they're easier to unlock & tune, and it's easier to get rid of silly stuff without the ECU instantly throwing a code if you happen to look at it crosseyed. This is all in the context of racing and/or offroad activities, not driving on the street, of course

I'm also a fan of not having the ignition ignitors onboard the main ECU, which is the way your 2.7 is setup, because it opens the door to using contemporary "smart" COP's with onboard ignitors, should you ever want to. With the ignitors onboard the main ECU, as the 5.2 is setup, we're limited to either dumb coils, or a CDI system.

So if I had the choice, I'd take a mature OBDI system anyday before an early OBDII system.

'99 550, Rosso Corsa / Nero, S/N:114654, Assy: 31836, Engine: 52084

High mileage, low compression, and missing on a few cylinders.....just like my cars.

Maranello Skunkworks Team Member
cribbj is offline  
 
post #4 of 6 Old 10-25-2012, 08:49 PM
Owner
Elite Member
 
tazandjan's Avatar
 
Join Date: Aug 2011
Location: Albuquerque, NM
Ferrari Life Posts: 11,881
Rik- If you want to do something, consider using one of John's COP kits to update the car. Remember also that Motronic 5.2 came with a develish alarm system with three matched fobs and two keys, an alarm ECU, and an immobilizer that cost quite a bit . If you put 5.2 DMEs on a 456, the engine will not start without a signal from the alarm/immobilizer ECU.

Sounds like more of a pain than it would be worth, not to mention that the 456M had a unique firing order only used once by Ferrari, I believe.

Late 456s, and not just 456Ms, came with 5.2 DMEs, by the way. If you look at your 456 WSM, you will note there are separate sections for Motronic 2.7 and 5.2.

Taz
Terry Phillips

Present: 575M 135171
Past: Dino 246 GT 02984, 365 GTB/4 14009, 308 GTS 25125

Every day I look around, and if nobody is shooting at me, it is a pretty good day.
tazandjan is online now  
post #5 of 6 Old 10-26-2012, 06:52 AM Thread Starter
Owner
 
Granucci's Avatar
 
Join Date: Jan 2007
Location: far and away
Ferrari Life Posts: 6,203
thanks all, I am convinced I should not consider this for some of the reasons of expense and lack of gain from the current pool of qualified mechanics wanting the [as Brian states] 'rushed to market' hatchet like jobs we can see for compliance reasons.

I agree: Rather have a seasoned engineered model than 'step up' in tech only to rework a new set of bugs. That's why COBOL has value in the ol' computing world.


Quote:
Originally Posted by tazandjan View Post
.....the 456M had a unique firing order only used once by Ferrari, I believe......
I had read the 'unique' firing order was more on the older GT and the M-series went to the 'regular' firing order Ferrari always had from 60's on. But, I would need to verify such.

-- now that I think about it, the CATs on the M series have an extra sensor and the shocks one less setting, and no foil interface [seperate ECU], perhaps making for an entire mess on the magement ECUs. I like my 456, now to get the overhead CAM seals replaced, steering lines replaced and that [now] pesky sounding exhaust leak or whatever

thank goodness it's winterish and I'm driving the truck. 456's are not good wet drivers in close stop-go traffic without giving plenty of driving space or traveling slow.

Guide to the Galaxy: Don't Panic
Rik -- LAH !


Current:
Past:
1990 Mondial T Cabriolet SN 86247 : Red/Tan
1995 456 GT 2+2 SN 99987 : Roso Metalizzato [Fer 311/C] & Tan

Last edited by Granucci; 10-26-2012 at 07:05 AM.
Granucci is offline  
post #6 of 6 Old 10-26-2012, 08:31 AM
Owner
Elite Member
 
tazandjan's Avatar
 
Join Date: Aug 2011
Location: Albuquerque, NM
Ferrari Life Posts: 11,881
Rik- The 456M had the unique firing order. Look in the owner's manual or look at the firing order/cylinder numbering thread in the knowledge base section.

Taz
Terry Phillips

Present: 575M 135171
Past: Dino 246 GT 02984, 365 GTB/4 14009, 308 GTS 25125

Every day I look around, and if nobody is shooting at me, it is a pretty good day.
tazandjan is online now  
Reply

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome
Copyright 2012 ONE Media, Inc.
FerrariLife is independently run with no affiliation with Ferrari SpA
Ferrari for Sale | Maserati for Sale