512 BB

Hi guys.
I'm new to the forum but was hoping you might be able to help me.
I have a 512 BB and it keeps cutting out after about 20 mins of driving. I've had it at the garage and they have replaced the coil and pick up sensor on the distributor. They say the next option is replacing or changing the dinoplex for a MSD box.
Is this the best option or are they missing something?
Thanks

 

It may be the best option. IF it is losing ignition and not something else.
Oddly enough, with a dinoplex you will hear a buzzing sound with the key on. I have had one that stopped buzzing and I knew that was the issue. I have worked on many Boxers and have installed many MSD boxes. Make sure it is not a power issue that is causing the failure.

 

Hi there.
Thank you for replying to me.
When you say power issue what do you mean?
There is a buzzing noise when the key is on but i thought it was the fuel pumps.

The one time it wouldn't start the mechanic came out and there was no spark, left it over night and it started no problem the next morning.

 

Listen for a high pitched whine of the Dinoplex. The fuel pump click, click, click is very different.

 

thank you yes i can hear that, but the last time i drove the car when it broke down i couldn't hear that at first then after a few minutes i could hear it again and it started back up. Looking at getting the MSD 6AL-2 box for the car now.

 

It could very well be related to a bad Dinoplex box. My box became significant weaker with temperature and I could hardly start the engine when hot. Remove one of the spark plug caps and hold the wire a few millimetres from the ground on the engine and try cranking the engine when cold versus warm while observing the intensity of the spark. I noticed a significant reduction in spark intensity when hot and opted to go MSD. Do a search in the boxer section for further MSD inspiration.

Best, Peter

 

Hi Peter.
Thank you for that information, my mechanic has ordered a MSD box. Anyone got any tips for fitting it?
Thanks

 

Contact MSD about getting it modified for 12 cylinder use. This allows the rev limit to work in its proper range. I have had it done on the older analog boxes but I haven't tried on the digital box.
When they (digital) came out they were terrible. I went through three sets of two on Daytona. They would stop firing and I would sent them back to MSD directly. The tech I was dealing with finally called back after the third set and told me a new set was coming my way and it should resolve the problem. I open the box and had two analog boxes. He had found new old stock and just sent the old style.
I had the same issue on a small block Chevy I built for a friend. I finally bought an analog off Ebay and no more issues. I understand that they are better now.

 

Here is a link for inspiration:

https://www.ferrarichat.com/forum/threads/512-bbi-ignition-upgrade.630245/

Here is a wiring diagram for exchanging the Dinoplex against an MSD 6AL-2 setup (Produced by Adrian):

http://www.dinoplex.org/PDF/Wiring_MSD6AL2_for_AEC104.pdf

And here is a link to a cheap unit....

https://www.ferrarichat.com/forum/threads/512-bbi-various-spare-parts.633515/

Good luck with the project.

Best, Peter

 

Hi Peter.

Thank you for that info, really helpful.
My mechanic has already ordered the MSD box and I've been reading up on it. Been told its only for up to 8 cylinders. How does it work with the 12 cylinder the 512BB has? I also saw something about the rev limits?

Many thanks

 

The 6-AL2 standard box is working fine with the 12 cylindered 512BB. Only abnormal adjustment you need to do is when setting the rev limit. Here you need to multiply the needed setting with 1.5 in order to compensate from 8 to 12 cylinders:

Image Unavailable, Please Login
That's basically it. No need for for any MSD company special modification.

Best, Peter

 

Crazy as it might sound but I would test the resistance of the distributor caps cold verses hot. I had a similar problem with a car after replacing a non Italian made distributor cap and found power loss after engine was warm. After trouble shooting all components I found that the new distributor cap had very high resistance, between internal contact and high tension lead connector, once warmed by the engine.

 

It may be a long shot, but my 328 had an issue like this - where it would not shut off when driving but once you parked it, it would die and not start back up... over night when cold - voila it re started. Turned out to be connectors were corroded in the wiring harness, on the fuel pump circuit... once we spliced in a new fuse and circuit it worked great for about a year then the next one in line burned out... same symption.. .did the same fix. Ultimately we bypassed that wire all together and re did the circuit with new wire ( more flexible - better conductor ) and it never happened again. could your wiring just be old - cracked .. once it gets hot the crack opens up, then cools and reconnects... ? all my fuses were in great shape... only tracking the circuit did we find the culprit ( down in passengers foot well in the 328)

 

As “Ferrari tech” was saying about power is that the 12 volt supply and grounds are good and can handle the load “ aka AMPs” needed going to your ignition and fuel systems
As we all know Ferrari wasn’t the best with wiring
My question is how did the mechanic determine the problem was the ignition control box
If the issue is that pronounced there are a lot of ways of pin pointing the problem before replacing parts
Nothing more annoying is that you replace something and still have a problem
I rather take the time to make sure that the upgrade will fix the problem


Sent from my iPhone using FerrariChat.com mobile app